Bi-Monthly Research Notes: Vol 29, No 1-6 - NFIS

increase temporarily in response to a short photoperiod. Noreference could be found to this phenomenon, which is describedhere because of its relevance to photoperiodic experiments incontrolled environments. Jack pine seedlings from Petawawa, Ont.(46°N 77°W) and Lac La Ronge, Sask. (55°N 105°W) were grownin a growth room at 22°C and 16 hr photoperiod. The growingmedium was turface which was watered automatically with anutrient solution four times daily (Pollard, Can. Forest. Serv. Inf.Rep. PS-X-28, 1971). After 9 weeks in the long photoperiod,seedlings were divided into three groups and placed in a shortphotoperiod (8 hr) in three growth cabinets at 15°, 20° and 25°Crespectively. Seven seedlings were selected at random for photosyntheticmeasurements in the long photoperiod and after 2, 4and 7 weeks in the short photoperiod. During the last 2 weeks inthe long photoperiod, the photosynthetic rate of both provenancesremained steady at 18 mg CO2/g needle/hr. After 2 weeks in theshort photoperiod photosynthetic rates had increased significantly(Fisher's t test, p 0.02), but subsequently declined to ratesbelow those obtained in the long photoperiod (Table 1). Theresponse was similar for both provenances and all temperatures.No diurnal fluctuations in photosynthesis could be detected ineither photoperiod.TABLE 1Photosynthetic rate (mgCO2/g needle/hr) of Jack pine seedlings from Petawawaand Lac La Ronge in a long photoperiod and after 2, 4 and 7 weeks in a shortphotoperiod at 15°, 20° and 25°C.Weeks inshort photoperiod0247Petawawa, Ont.15° 20° 25°221811a Seedlings in a long photoperiod at 22°C.24 2520 2117 17The "source-sink"-hypothesis that actively growing sinks forphotosynthates influence rate of photosynthesis (Sweet andWareing, Nature 210:77-79, 1966) suggests an explanation for thisphenomenon. The actively growing "sinks" may be maintainedfor the first 2 weeks in the short photoperiod. In this connection,Kawase (Amer. Soc. Hort. Sci. 78:532-544, 1961) found no changein growth rate of yellow birch [Betula alleghaniensis Britt.] untiltheir third week in a short photoperiod. If the photosyntheticrate were to remain unchanged in the 8 hr photoperiod, seedlingswould produce only half as much photosynthate as in the 16 hrphotoperiod. The subsequent increase in photosynthetic rate is inresponse to the continuing demands of the actively growing"sinks". However, short photoperiods upset the balance ofgrowth regulators and induce dormancy (Phillips and Wareing,Naturwiss. 13:317, 1958). As growth slows down, demand forphotosynthate slackens and the photosynthetic rate declines.-K.T. Logan, Petawawa Forest Experiment Station, Chalk River,Ont,ENTOMOLOGYLac La Ronge, Sask.15° 20° 25°18a22 24 2419 21 2110 15 14Biological Control of the European Spruce Sawfly in Newfoundland.—TheEuropean spruce sawfly [Diprion hercyniae(Htg.) ] was first recorded in Canada in 1930 on the GaspePeninsula, Quebec. By 1940, it had spread throughout NewBrunswick and severely defoliated many stands of black andwhite spruce (Bird and Elgee, Can. Entomol. 89:371-378, 1957).In the same year it was discovered in the Humber Valley inwestern Newfoundland and had spread to the Baie Verte andnorthern peninsulas by 1948 and into central and eastern areasby 1959. Survey records, obtained from beating infested treesindicate that population levels increased from an average of 20larvae per sample to 90 larvae per sample between the years1943 and 1951 and between 1958 and 1970 (Fig. 1). Duringthese periods defoliation was severe in some stands but treemortality was negligable.Ea 01;1005co1WesternCentralEastern1940 45 50 55 60 65 1970YearsFigure 1. Outbreaks of the European spruce sawfly in Newfoundland.Damage is caused by the larvae feeding on the needles ofhost trees, primarily the spruces. White spruce is the preferredhost but both red and black spruce may be severely defoliated.Several years of severe defoliation can cause tree mortality andmore than 10 million cords (36 million cubic meters) of sprucewere killed in the 190's in Quebec (Reeks and Barter, For.Chron. 27:140-156, 1951).The extensive areas of defoliation and the history of treemortality in Quebec, prompted Newfoundland Forestry Officialsto introduce the nucleopolyhedrosis virus [Borrelinavirus hercyniae]a key factor in the reduction of sawfly numbers in NewBrunswick (Neilson and Morris, Can, Entomol. 96:773-784, 1964).The virus was obtained from the Maritime Forest ResearchCentre, Fredericton, N.B., and applied as a liquid suspension tosawfly-infested white spruce trees in the Humber Valley in 1943and 1944. It established readily but appeared to disperse slowly;in 1948 the virus was applied again to infested trees on the BaleVerte Peninsula. It was also introduced into new infestations onthe Northern Peninsula by releasing virus-infested larvae collectedin the Humber Valley area. The virus dispersed rapidlyand was apparently the primary factor contributing to the collapseof infestations early in the 1950's (Fig. 1). In the late 1950'ssawfly numbers increased again, averaging 90 larvae per tree incentral, and 25 per tree in western Newfoundland ; even highernumbers have been recorded since 1960, These recent periods ofhigh population have lasted only 1 or 2 years as opposed to the5-8 year period recorded for the initial outbreak. The virus wasassumed to be the principal factor in shortening the outbreakperiod but the introduction of invertebrate parasites and themasked shrew have doubtlessly improved the biological controlcomplex of this sawfly.Insect parasites of the European spruce sawfly were introducedfrom Europe between the years 1943 and 1949. Theseincluded species of Hymenoptera; Dalbominus fuscipennis (Zett.),Exenterus amictorius (Panz.) and E. confusus Kerr; and a Diptera,Drino bohemica Mesn. released in infested stands in western2

Renault, T. R., and C. A. Miller. 1972. Spiders in a fir-spruce biotype:abundance, diversity, and influence on spruce budworm densities.Can. J. Zool. 50:1039-1046.Rennie, P. J. 1972. The role of mechanization in forest site preparation.pp 63-102 in Techniques in Silvicultural Operation. Paperspresented at the XV IUFRO Congress 1971, IUFRO Div. No. 3."Forest Operations and Techniques" Pub. No. 1. Stockholm.207 p.Richards, W. C. and Y. Hayashi. 1972. Preferential separation ofcytoplasmic-polyhedrosis virus (CPV) RNAs from infectedmidgut cells. J. Invertebr. Pathol. 20(2):200-207.Scarratt, J. B. 1972. Air space controls root extension from openendedcontainers during seedling production. For. Chron. 48(October).Shen, K. C. and P. C. Fong. 1972. A new method for makingparticleboard fire-retardant. Forest Prod. J. 22(8):46-52.Smirnoff, W. A. et J. R. Valero. 1972. Perturbations métaboliqueschez Choristoneura fumiferana Clemens au cours de l'infectionpar Bacillus thuringiensis seul ou en presence de chitinase. Rev.Can. Biol. 31(3):163-169.Smith, R. B. 1972. Relation of topography and vegetation to theoccurrence of Douglas-fir dwarf mistletoe at its northern limitsin British Columbia. Ecology 53(4):729-734.Steucek, G. L. and R. M. Kellogg. 1972. The influence of a stemdiscontinuity on xylem development in Norway spruce, Piceaabies. Can. J. Forest Res. 2:217-222.S ieda, C. K. A. 1972. Application of finite-element methods foranalysis of composites. pp 255-285 in Theory and Design ofWood and Fibre Composite Materials. Syracuse Univ. Press.Syracuse, N.Y.Strang, R. M. 1972. Ecology and land use of the barrens of westernNova Scotia. Can. J. Forest Res. 2:276-290.Swann, G. W. and J. W. Rolf. 1972. Lab test suggests anti-strain dipeffective on frozen wood. Can. Forest Ind. (May).Troughton, G. E. 1972. Kinetics of condensation reactions of modelphenolic compounds. Holzforschung 26(5):170-173.Troughton, G. E. and J. F. Manville. 1972. Lignin utilization. I.Kinetics of base-catalyzed condensation reactions of lignin modelcompounds. Can. J. Forest Res. 2:271-275.Troughton, G. E., J. F. Manville and S.-Z. Chow. 1972. Lignin utilization.II. Resin properties of 4-alkyl substituted catechol compounds.Forest Prod. J. 22(9):108-110.Venkateswaran, A. 1972. A note on densities and conductivities ofwood. Wood Sci. 5(1):60-62.Warren, W. G. 1972. Point processes in forestry. pp 801-816 in StockPoint Processes (c) 1972. John Wiley & Sons, Inc. New York.Whitney, H. S. and F. W. Cobb, Jr. 1972. Non-staining fungi associatedwith the bark beetle Dendroctonus brevicomis (Coleoptera:Scolytidae) on Pinus ponderosa. Can. J. Bot. 50:1943-1945.Whitney, R. D., W. P. Bohaychuk and M. A. Briant. 1972. Mycorrhizaeof jack pine seedlings in Saskatchewan and Manitoba. Can.J. Forest Res. 2:228-235.Yoshimoto, Carl M. 1972. A new species of Achrysocharis (Eulophidae:Chalcidoidea) from pine needle scale (Diaspididae:Homophera). Can. Entomol. 104:1483-1485.Zoltai, S. C. 1972. Palsas and peat plateaus in central Manitoba andSaskatchewan. Can. J. Forest Res. 2:291-302.8

ecent publicationsJANUARY -- FEBRUARYBonga, J. M. 1971. Formation of holdfasts, callus, embryoids and haustorial cells in the in vitro culturesof dwarf mistletoe Arceuthobium pusillum. Phytomorphology. 21(2-3):140-153.Bonnor, G. M. 1972. A test of 3-P sampling in forest inventories. For. Sci. 18:198-202.Cayford, J. H. 1972. Container planting systems in Canada. For. Chron. 48 (October).Cerezke, H. F. 1972. Observations on the distribution of the spruce bud midge (Rhabdophaga swaineiFelt) in black and white spruce crowns and its effect on height growth. Can. J. Forest Res. 2:69-72.Chafe, S. C. and Mary E. Doohan. 1972. Observations on the ultrastructure of the thickened sieve cellwall in Pinus strobus L. Protoplasma. 75:67-78.Chow, S.Z. 1972. Infrared spectral study of woody tissues from four conifers. Wood Sci. 5(1):27-33.Durzan, D. J., J. Pitel and P. K. Ramaiah. 1972. Acid soluble nucleotides and ribonucleic acids fromgerminating jack pine seeds. Can. J. Forest Res. 2:206-216.Ebell, L. F. 1972. Cone-induction response of Douglas fir to form of nitrogen fertilizer and time oftreatment. Can. J. Forest Res. 2:317-326.Ebell, L. F. 1972. Cone-production and stem-growth response of Douglas fir to rate and frequency ofnitrogen fertilization. Can. J. Forest Res. 2:327-338.Edwards, D. G. W., and P. E. Olsen. 1972. R-55 rodent repellent: Effect on germination in Douglas-firand western hemlock. Can. J. Forest Res. 2:256-263.Eis, S., and J. R. Long. 1972. Lateral root pruning of Sitka spruce and western hemlock seedlings. Can.J. Forest Res. 2:223-227.Fung, D. P. C., Yoshio Tsuchiya and Kikuo Sumi. 1972. Thermal degradation of cellulose and levoglucosan- The effect of inorganic salts. Wood Sci. 5(1):38-43.Fye, It. E. 1972. The effect of forest disturbances on population of wasps and bees in northwesternOntario (Hymenoptera: Aculeata). Can. Entomol. 104:1623-1633.Golding, D. L. and R. L. Harlan. 1972. Estimating snow-water equivalent from point-density measurementsof forest stands. Ecology. 53(4):724-725.Hatton, J. V. and J. L. Keays. 1972. Complete-tree-utilization studies. III. Yield and quality of kraft pulpfrom the components of Pseudotsuga menziesii. Tappi. 55(10):1505-1508.Heimburger, C. C. and C. R. Sullivan. 1972. Screening of haploxylon pines for resistance to the whitepine weevil. I. Pinus peuce and P. strobus grafted on Scots pine. Silvae Genetica. 21(3-4):93-96.Heron, R. J. 1972. Differences in postdiapause development among geographically distinct populations ofthe larch sawfly, Pristiphora erichsonii (Hymenoptera: Tenthredinidae). Can. Entomol. 104:1307-1312.Hocking, Drake and Fred D. Cook. 1972. Myxobacteria exert partial control of damping-off and rootdisease in container-grown tree seedlings. Can. J. Microbiol. 18:1557-1560.Huffman, D. R., F. Pfaff and S. M. Shah. 1972. Azeotropic drying of yellow birch and hard maple lumber.Forest Prod. J. 22(8) : 53-56.Keith, C. T. 1972. Cellulose DP measurements on wood stressed in longitudinal compression at subfailurelevels. Pulp Pap. Mag. Can. 73(11):T345-T346.Krywienczyk, J. and Y. Hayashi. 1972. Serological investigations of sub-cellular fractions from Malacosomadisstria larvae infected with cytoplasmic polyhedrosis. J. Invertebr. Pathol. 20:150-156.Lees, J. C. 1972. Soil aeration and sitka spruce seedling growth in peat. J. Ecol. 60:343-349.Lüthy, P. and J. Krywienczyk. 1972. Serological comparison of three milky disease isolates. J. Invertebr.Pathol. 19:163-165.Marshall, V. G. 1972. Comparison of two methods of estimating efficiency of funnel extractors for soilmicroarthropods. Soil Biol. Biochem. 4:417-426.Marten, Gerald G. 1972. Researches on population ecology. Res. Popul. Ecol. 14(1):36-57.McMorran, Arlene. 1972. Effects of some environmental factors on the occurrence of second diapausein laboratory-reared Choristoneura fumiferana (Lepidoptera: Tortricidae). Can. Entomol. 104:1649-1653.Moore, Mary I. 1972. New form of Thuja occidentalis resembling known cultivars. Rhodora. 74:352-357.Morris, R. F. 1972. Predation by wasps, birds, and mammals on Hyphantria cunea. Can. Entomol.104 : 1581-1591.(Continued on page 7)

i-monthlyresearchnotesSurvival of European pine shoot moth on Christmas treesResidual toxicity of six insecticidesSurvival of balsam woolly aphid on amabilis firEffect of cold treatment on post-diapause spruce budworms19-norisopimara-8(14),15-dien-3-one in Thuja plicata barkIsolation of a-atlantone from alpine firRapid-growing precocious white spruce provenancesSquirrel damage on Norway spruceComparison of four methods of pH determinationVol. 29, No. 2, MARCH-APRIL, 1973.I 4pp Environment EnvironnementCanada CanadaForestry ServiceService des forêts

IVbi-monthlyresearch notes"A selection of notes on current research conducted bythe Canadian Forestry Service and published under theauthority of the Minister of the Department of theEnvironment. A French edition is published underthe title of Revue Bimestrielle de Recherches".ENTOMOLOGYSurvival of European Pine Shoot Moth on Cut ChristmasTrees.—The European pine shoot moth [Rhyacionia buoliana(Schiff.)] is a threat to native pine forests of British Columbia,and already is established in oranamentals and exotic nurserystock in southern coastal areas. Until this study was completed,the movement of cut Christmas trees, Pinus spp., intoand within British Columbia was permitted without treatmenton the assumption that the insect could not overwinter on cuttrees. As there was no experimental evidence to indicate thebehavior of R. buoliana on such material, a study was made todetermine possible survival.Twenty-two infested Scots pine [P. sylvestris L.], a typicalcommercial species, were cut 30 Nov 1971, near Seattle, Wash.,and brought to Victoria. They were treated as Christmas trees,without benefit of preservative, nutrient or protection, and setupright outdoors on a northern exposure, with bases in about8 cm (3 inches) of sand. These conditions were consideredthe optimum likely circumstances for trees remaining outsideas decor, or discarded and partly buried in earth-fill or garbage.Trees averaged 1.2 m (4 feet) in height, and had about 350tips, of which approximately 30% were infested at the time ofcollection. About one-quarter of larvae were third instar,the remainder fourth. Three control trees were checked twiceweeklyfor moisture stress by "bomb test" (Scholander et al.Sci. 148:339-346, 1965). Healthy potted lodgepole pine [P.contorta Dougl.] were placed with the Scots pine to determineif larvae could transfer.Three trees, including one control, were taken indoors forthe Christmas season (12 days) and kept without water atnormal room temperature and humidity. Larvae on these treesbegan active feeding, and about 10% attained fifth instar. However,as the trees dehydrated, about half the larvae left thebuds and died and most of the remainder, including those infifth instar, died soon after they were returned outdoors. Afew lived until March, by which time the trees had lost nearlyall their needles, and the moisture stress had increased to 16from 2 atm.Two outdoor trees were dissected each month to assessthe insect population (Table 1). By the end of January, mostof the larvae had become fourth instar without significant mortality.During the winter's coldest 5-day period, 24-28 Jan1972, the average minimum temperature was 18 F, and thewind chill factor for one day averaged —12 F. Althoughrelatively cold for the area, this would have had little effecton normally overwintering R. buolina that may withstand temperaturesof —20 F. By the end of February approximately44% of larvae had died, while some of the living larvae haddeveloped to fifth instar. No appreciable mortality occurredTABLE 1Survival of R. buoliana on outdoor treesDate No. of trees Avg no. living Instarsexamined insects/tree presentNov. 30 2 101 III, IVDec. 31 2 98 III, IVJan. 31 2 95 III, IVFeb. 29 2 56 III, IVMar. 30 2 52. VMay I 2 10 V, VIJune 12 5 8 VI, pupaein March, but during April 83% of the remaining larvae died,leaving about 10% of the original population alive. DuringMay, the larvae developed to ultimate instar with little furthermortality. Final bud dissections in early June revealed 14mature larvae and 27 healthy pupae on the five remainingtrees, a 12% survival of the original larval population estimatedfor five trees. Eleven adults emerged before the materialwas destroyed to prevent possible contamination; theyappeared normal and no check was made of their fecundity.The first significant larval mortality, during February, waslikely due to the rapidly deteriorating food and shelter conditionsthat forced the larvae to leave the buds and subsequentlysuccumb to the inclement weather. The second mortality crestin April probably resulted indirectly from warming daytimetemperatures that encouraged the larvae to move about in afutile search for food and more adequate shelter, that normallywould have been readily available. At that time, larvaemoved onto adjacent potted lodgepole pine that had beenincluded to test this possibility. Most of these "transferred"larvae survived on the living trees.There is no doubt that R. buoliana may survive and successfullydevelop on cut trees left outdoors, even though theexperiment coincided with local conditions relatively favorablefor the insect, i.e., few dehydrating periods of wind or warmth.Larvae on cut trees can transfer to adjacent living pine. Insectsurvival might be higher in cooler regions where snow covercould provide added protection, and on less heavily infestedtrees that would presumably retain food-shelter value longer.Christmas trees taken indoors offer little chance for larvae tocomplete development. It must be stressed that any insect survival,no matter how minimal, is critical.As a result of this study, quarantine regulations wereadjusted to include mandatory fumigation and seasonal restrictions(Can. Dep. Agr., Plant Prot., Export Control Circ. No.17C, 1972. B.C. Laws, Statutes, etc. 1972; Order in Council,minute No. 3748).—David Evans, Pacific Forest ResearchCentre, Victoria, B.C.Evaluation of Residual Toxicity of Six Insecticides forControl of Sitka Spruce Weevil.—The most recent study onchemical control of Sitka spruce weevil [Pissodes strobi (Peck)(= Pissodes sitchensis (Hopkins)] was conducted in BritishColumbia during 1961-1964 by Silver (Can. Ent. 100:93-110,1968). He suggested that control is possible but uneconomicalon a large scale, unless applied as aerial spray. Accordingly,six candidate insecticides, Gardona®, propoxur, benzene hexachloride(gamma isomer), phosphamidon, Methyl Trithion®,and fenitrothion, were tested in 1970 and 1971 to determinethe residual toxicity for weevil control under West Coast conditions.In laboratory tests, the latter four insecticides hadpreviously shown promise for controlling Sitka spruce weevil(Nigam, Can. Forest. Serv., Inf. Rep. CC-X-3, 1969, 9 pp.).Sitka spruce [Picea sitchensis (Bong.) Carr.] saplings, 1-2in tall, were transplanted in February 1970 from the PortRenfrew area to a 1.5 x 1.8 m spacing outdoors at the PacificForest Research Centre, Victoria. The 1969 leaders averaged50.3 cm in length (range 35-61 cm), 8.4 mm mid-point diameter,and 133 cm2 bark surface area. Five trees were assignedrandomly from each of the six test groups and a control.Each leader was isolated by a polyethylene sheet andsprayed during still-air conditions during the morning of 6 July,1970. Insecticides were formulated as water-based emulsionscontaining 10% active ingredient (a.i.), except benzene hexachloride(5% a.i.). Application was made with a "Spray onJet-Pack Sprayer" (Sprayer Product Inc., Los Angeles, California),depositing about 0.01 ml/cm' (about to the point ofrun-off). Test weevils used until August 18 were field collectedin May and June and held on fresh host material in a refri-9

gerator until used; thereafter, weevils emerging from currentlyinfested leaders were used. Until that date all weevils weresexed (Harman and Kulman, Ann. Ent. Soc. Amer. 59: 315-317,1966). Twenty-four hours after spraying and at 2-week intervalsthereafter, four adult weevils (2 males and 2 females)were introduced into a screen-sleeve cage (1 mm mesh) placedover each leader. On August 18, a comparison of mortalitybetween males and females, and old (field-collected) and young(newly emerged) adults showed no significant differences, andsubsequently the weevils were not sexed.Within 24 hours after the first introduction, about 90%mortality had occurred in all groups except propoxur (50% )and the control (0% to the end of the tests). Mortality forthe seven introductions assessed 48 hours after each introductionis shown in Fig. 1. The insecticides, in descending effectiveness,were: Gardona®, Methyl Trithion®, fenitrothion,benzene hexachloride, propoxur and phosphamidon.100800 6402FENI- METHYLPHOSPH- BENZENETROTHION TRITHION GARDONA AMIDON HEXACHLORIOE PROPOXUR10% 10% 10%10% 5% 10%1 1111I1I 111 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1EACH SPACE 14 DAYS (1970)Figure 1. Residual toxicity of various insecticides over 14 weeks,showing percent mortality of weevils within 48 hrof introduction on to pre-sprayed trees.>-I-010080604020FENITROTHIONI % 2% 2%METHYL TRITHIONI% 2% 2%111 LIJ I I 1 I 1 I IIIIIIIIIIIIII WEEK INTERVALS 1971Figure 2. Percent mortality of weevils 48 hr after introductionat different periods of time following insecticideapplication.-77Further tests, conducted in 1971, used the more effectiveinsecticides, Methyl Trithion® and fenitrothion, at more ecologicallyacceptable levels (1 and 2% a.i.). Gardona® waseliminated because it was thought to be toxic to fish (Tech.Bull. Gardona Insecticide, Shell Chemical Co., New York),but this decision needs to be reconsidered because anotherreport (Thompson, Agricultural Chemicals Book I Insecticides1972 revision) indicates that the insecticide is relatively nonhazardousto fish. The same methods and materials as in 1970were used, except that introduction of weevils was weeklyinstead of biweekly. The interval was changed from 1970because lower concentrations of insecticides were used, andreduced residual toxicity was anticipated. Tests started onJune 28, with new groups of trees, indicated that only 2%concentrations were effective (Fig. 2); mortality on unsprayedtrees was nil. On July 12 additional groups of trees weresprayed with 2% concentrations. The early mortality wassimilar to that of the prior test and the residual toxicitygradually decreased after the first week (Fig. 2). Reductionin toxicity of fenitrothion was more gradual than MethylTrithion® in the early period after application, but the latterretained some toxicity to the end of the 6-week test period.These results show that of the insecticides tested, fenitrothionand Methyl Trithion® at 2% minimum concentrationswere the most promising for control of the Sitka spruce weevil.They appear suitable for further testing in ground applicationand aerial spray under field conditions.—S. Ilnytzky, PacificForest Research Centre, Victoria, B.C.Establishment and Survival of Balsam Woolly Aphid onSecond Growth Amabilis Fir at Intermediate Elevations.—Regeneration of many cutovers at intermediate elevations toamabilis fir [Abies amabilis (Dougl.) Forbes] is desirable inBritish Columbia in view of the frequent failure of otherspecies, e.g. Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco]at these elevations. However, planting of Abies ceased in 1966,when the province imposed quarantine regulations on thecommercial growing and transport of A bies. These regulationsresulted from the threat of the balsam woolly aphid [Adelgespiceae (Ratz.)], an insect pest of Abies for which there is nopractical control. Although the aphid is now concentratedin high-value, old-growth stands, the possibility of dispersalinto regenerated stands is increasing as the supply of oldgrowthtrees dwindles. Whether it will establish and surviveon young second-growth amabilis fir at elevations above 2000ft (610 m) is uncertain.Three study areas, located at various elevations withinthe aphid infestation zone, were selected in the Haslam Creekwatershed west of Ladysmith, B.C. The forest cover waspredominantly second-growth amabilis fir, 15-30 yr old.Table 1 shows the size of sample, elevation and stand characteresticsin the three areas. In an initial crown sampling andstem inspection of all trees in July 1969, no aphids were found.In August, pieces of aphid-infested bark, each bearing approximately50 eggs, were collected from low elevation grand fir[A. grandis (Dougl.) Lindl.] near Ladysmith and used toinfest the study trees. On each tree, two pieces were tapedto the stem, one at breast height and one 12 ft (3.7 m) abovethe ground, and two pieces were tied to twig ends in the mid-TABLE 1Characteristics of second-growth amabilis fir stands selected for studyNo. of Elevation Stocking Dbh Heighttrees ft (m) (stems/acre) inch (cm) ft (m) Aspect18 2300 (701) 200 8-10 (20-25) 30-40 (9.1-12.2) NW36 2850 a (869) 450 4-8 (10-20) 25-35 (7-6-10.7) W18 3500 (1067) 900 4-8 (10-20) 20-30 (6.1- 9.1) ERange of elevtation 2700-3000 ft (825-918m).10

crown, thereby exposing four sites per tree to the aphid.Infestations on the stem were located so they were not exposedto direct sunlight. Plastic flagging tape was tied around thestem about 6 inches (15 cm) above each piece of bark. Sincethese trees were uniformly smooth-barked, the tape servedto simulate lichen or moss under which future generationsof aphids could gain protection. When the bark pieces wereremoved in September, aphids had settled on all trees andat all 288 sites.Each infestation was observed annually but the plastictapes were not removed for aphid counting until 1972. Fortwig infestations, the entire internode was checked; on thestem, the bark within 4 inches (10 cm) of the infestationcenter was checked. Aphids were counted at the end of ageneration when the population was mostly wool-bearingadults, and each infestation was classified as either 0, 1(light; 1-10 aphids), 2 (moderate; 11-50) or 3 (heavy; > 50).Each tree was rated, using these infestation categories, e.g.a tree with two light and two moderate infestations wasrated 6. From these tree ratings, an Infestation Index wascalculated for each elevation to provide a cumulative measureof initial establishment, survival and population change.Infestation Indexsum of maximum tree infestation ratings (=4X3Xno. trees)Xsum of individual tree infestation ratingsIn 1970, at the end of the summer generation, infestationsat 2300 ft and 2850 ft were 65-69% of maximum butonly 53% at 3500 ft (Table 2), indicating that establishmentin 1969 and/or 1970 population growth was less at the higherelevation. The count in mid-July 1971, at the end of the overwinteringgeneration, indicated that winter mortality increasedwith elevation. The Infestation Index decreased, 68% at2300 ft, 74% at 2850 ft, and 78% at 3500 ft. By August 1972,at the end of the summer generation, all exposed infestationson the twigs and stems had died out. The aphids, however,did survive in protected areas. When the plastic tapes wereremoved from the stems, aphids were found on most trees(Table 2). Furthermore, examination of twig nodes adjacentto the infestation sites revealed that progeny of the initial twiginfestation had settled under old bud scales and survived. Thusaphids survived in protected sites on the majority of treesfor at least 3 years, with infestation ratings 20-32% of maximum.Although the populations were relatively low on alltrees in 1972, they may have been increasing when counted.Continued observation was impossible, since the aphids hadto be eradicated in 1972 to prevent possible spread into thesurrounding stand.Aphids infesting exposed sites on twigs or bark apparentlyhave little chance for success. No tree exhibited anincrease in infestation rating from year to year, regardless ofelevation. The initial stem populations, which in 1970 wereconfined to an area about 2 inches (5 cm) square, did notdisperse except to protected sites under the tape. Likewise,the only dispersal of twig populations was to the protectionof bud scales.The balsam woolly aphid will apparently establish andsurvive in twig nodes of second-growth fir at intermediateelevations. However, the lower Infestation Index and incidenceof crown attack at 3500 ft indicates that populationsmay be less viable at that elevation. This has important implications,since a crown infestation normally produces offspringwhich infest the stem and tree mortality in BritishColumbia is associated mainly with stem attack. Furthermore,aphids infesting the stem have difficulty surviving unless protectedsites, e.g. lichen, moss, bark fissures, etc., are a commonfeature of the stand. At 3500 ft, low winter temperaturesare undoubtedly a major factor limiting aphid survival,TABLE 2Survival of balsam woolly aphid and infestation trends on second-growthamabilis fir at intermediate elevations2300 ft 2850 ft 3500 ft(701 m) (869 m) (1067 m) __Exposed sites1969Trees infested: crown 18 36 18stem 18 36 181970Trees infested: crown 18 35 18stem 18 36 18Infestation Index 65 69 531971Trees infested: crown 8 15 3stem 17 30 13Infestation Index 21 18 121972Trees infested: crown 0 0 0stem 0 0 0Infestation Index 0 0 0Protected Sites1972Trees infested:crown (bud scales) 13 22 5stem (under tape) 14 30 14infestation index 31 32 20but the summer drought which frequently occurs at higherelevations may be equally important. Results of a recentstudy at this laboratory (unpublished) indicate that, on treesreceiving a reduced water supply, balsam woolly aphid survivalis decreased and development is delayed.Before any recommendations can be made regardingamabilis fir regeneration, the development of aphids at intermediateelevations and their impact on second-growth standsmust be assessed over a longer time period.—J. R. Carrow,Pacific Forest Research Centre, Victoria, B.C.Effect of Cold Treatment on Post-diapause Spruce Budworms.—Inrearing post-diapause larvae and pupae of sprucebudworm [Choristoneura fumiferana (Clem.)] at diurnal fluctuatingtemperatures of amplitude 16.7°C with means of10.0°, 12.8°, 15.5°, and 18.3°C, we have found that survivalwas drastically reduced in the lower temperature regimes(unpubl.). Survival was particularly poor at a mean of 10°C(range 1.7° to 18.3°C) among larvae and female pupae. Thesurviving adults had deformed wings and failed to produceprogeny. The experiment had not given a good measure ofpupal survival because the pupae had been selected and preconditionedby the low larval rearing temperature. The cooltemperature regime did not simulate the sort of day thatpeople generally regard as cool, which would be humid, cloudy,and have a narrow temperature range. The temperature rangeof 16.7°C is typical of the clear, dry, sunny days found incontinental air masses over central and northern New Brunswickduring June and July. Such weather is regarded as favorablefor spruce budworm survival (Greenbank, Mem. Entomol.Soc. Can. 31: 19-23, 1963). Our observations led usto ask if survival is more effectively reduced when any particularpost-diapause stage is exposed to the cool temperatureregime with broad amplitude, and if survival is affectedby the duration of the treatment.Spruce budworm larvae were collected from an epidemicfield population near Juniper, N.B. by dislodging larvae fromexcised branches of balsam fir [Abies balsamea (L.) Mill.]onto a white sheet. The larvae were in the third to fifthinstars, but most were in the fourth. They were immediatelytransferred to 1 oz. plastic cups with corrugated sides, waxedcardboard covers, and a supply of artificial insect diet (Mc-Morran, Can. Entomol. 97: 58-62, 1965) in the bottom.Five larvae were placed in each cup. Extremely large orsmall larvae were rejected and larval size bias was avoided11

within cups by stocking several simultaneously. The cupswere selected for treatment at random. The cups with larvaewere then stored in an ice chest until put into the experimentalsituation cabinets 24 hours later. Larvae that failedto establish in the next 2 days were replaced; larvae laterfound to harbor parasites (about 3% Apatiteles fumiferanaeViereck and Glypta fumiferanae Viereck) were rejected.When not undergoing treatment, larvae were reared ina controlled environment cabinet, with a mean of 18.3°Cprogrammed to fluctuate on a sine curve between 10° and26.7°C. This is the regime we had previously found mostsatisfactory for growth and survival. The cool temperaturetreatment had a mean temperature of 10°C (range 1.7° to18.3°C) in a similar cabinet. Both of these regimes approximatedaily fluctuations that normally occur during the latelarval and pupal development of the spruce budworm in thespruce-fir forests of New Brunswick.The larvae were divided into four lots of 150 (5 larvaein each of 30 cups) according to when the cool treatment wasto begin. The first lot was placed in the cool treatmentimmediately; the other three lots were placed in the cooltreatment I, 2, and 3 weeks later. Each lot was divided intothree sub-lots of 50 larvae (10 cups) which were treated for1, 2, and 3 weeks. Thus there wer budworms subjected to threedurations of cool treatments begun at four different times orstages of development.Moths were mated and females oviposited in the 10°-26.7°C cabinet. Females were invariably paired with malesfrom the same treatment.As expected, the duration of development increased asthe duration of the cool treatment was increased (Table 1).To emergence, the duration increased about 4 days for eachweek of cool treatment. Most budworms treated 3 weeksTABLE IMean development times from collection to eclosion (in days) of sprucebudworms reared in a cool temperature regime for various durationsat various timesWeeks before cold treatmentDuration(weeks) (1 1 2 336.1** 35.7** 38.8** 33.12 41.5* 41.5** 'r 38.03 44.1* 45.0** 46.5** 41.3Differences significant at 1% level (**) or 5% level (*) from thosetreated after pupation for same duration using Student's 1 test.after the beginning of the experiment had already pupated,thus mean larval development was faster and mean pupaldevelopment was slower than in the other treatments. However,mean development time to emergence of those treatedafter most had pupated was significantly less than thosetreated before pupation (Table 1); the heat of developmentabove 6.1°C was generally about 22 degree-days less (inthe 10°-26.7°C cabinet, heat accumulated at the rate of 12.2degree-days/day).Larval survival among treatments was between 63 and78%, pupal survival was between 81 and 100%, and overallsurvival was between 53 and 71%. There was no relationshipbetween survival and duration of time of cool treatment.Mean pupal weights of female budworms first subjectedto the cool treatment in the third week after collection (106-113 mg) were 40 to 66% higher than those in other treatments(68-81 mg). Likewise pupal weights of male budworms(65-76 mg) were 18 to 43% higher than those in other treatments(53-56 mg). There were no differences in pupal weightwhere treatment began immediately, 1 week, and 2 weeksafter the experiment began. The duration of the cool treatmentdid not affect the mean pupal weight.The sex ratio varied from .36 to .59 with no apparentrelationship to treatment. Data on fecundity and hatch werenot obtained because mating success was not measured. However,among those pairs treated before pupation, the proportionof pairs producing progeny tended to increase with increasingduration of the cool treatment. The opposite trendoccurred among pairs treated after pupation.We cannot account for the fact that rearing fourth- tosixth-instar larvae and pupae of spruce budworm at a cooltemperature regime for up to 3 weeks had no effect on survivalalthough survival had been poor when the cool temperatureregime was continuous. Nor can we explain why there wasgreater delay of overall development when the cool treatmentwas applied to larvae than when it was applied to pupae,except to speculate that the larvae are more sensitive. Somemoths emerged in the cool regime, and their pupae thus hada curtailed treatment, but their numbers were insufficient toaffect the data.Pupal weight was much lower when the cool treatmentwas applied to larvae rather than pupae probably because ofinterruption of normal feeding and growth. Projections fromthis experiment on the size of the next generation were difficultto interpret because the contributions of mating success,fecundity, and fertility were unknown. We did not analyzefor possible effects on the moisture content or quality of thediet but there were no visible differences among treatments.Miller (Can. J. •Zool. 35: 1-13, 1957) found among fiieldcollectedpupae that high pupal weight is correlated with highfecundity. Our results suggest that survival to the next generationis affected by low temperature acting on the malesor females, or both, and the effect may be powerful enoughto mask any correlation with pupal weight.—D. C. Eidt andMargaret D. Cameron, Maritimes Forest Research Centre,Fredericton, N.B.FOREST PRODUCTS19-Norisopimara-8(14), 15-dien-3-one in Thuja plicataBark—Previously the isolation of 4a- and 4p-hydroxy-19-norsopimara-8(14),15-dienes, together with an unidentifiedketone, from the petroleum ether extract of western redcedar [Thuja plicata Donn] bark has been reported (Quonand Swan, Can. J. Chem. 47:4389-92, 1969). The unidentifiedcompound has now been identified as 19-norisopimara-8(14),15-dien-3-one (I). This compound (in amounts insufficientfor characterization) has been isolated from the bark ofPinta sylvestris (Norin and Winnell, Acta Chem. Scand.25:611-13, 1971), together with its 13-epimer in largeramounts. Also, it was synthesized during a sequence of reactionson a related compound by Grant and Minto (TetrahedronLetters: 3729, 1965).11 13 ** 17CH3CH 3 H C 15 16142 10 8A3C H318H12

Compound I, isolated by chromatographic techniques fromthe bark extract in 0.04 percent yield (o.d. bark) had m.p.52-54° and [a]u"° —52.4° (c 1.4 chloroform); its physicalconstants were not given by Norin and Winnell, and Grantand Minto (op. cit.) gave only m.p. 46-48°. Compound Ireacted with ethylene glycol and acid catalyst to yield the3-ethylene ketal derivative, m.p. 112-114°, with a m.w. (massspectrum) of 316.2400 (calc. for C 21H3202 316.2401). Theproton magnetic resonance (p.m.r.), infrared (i.r.) and massspectra of these compounds were consistent with structure Iand its 3-ethylene ketal.Other data supporting the structure were as follows: Thei.r. spectra of I, 19-norpimara-8 (14), 15-dien-3-one and isopimara-8(14),15-dien-3-onewere almost identical, as weretheir thin-layer chromatography R t's and color reactions. Thep.m.r. spectra of these three compounds were practically identical,except for the extra methyl signal at 8.95 T in thespectrum from isopimara-8(14),15-dien-3-one and the differentappearance of the vinyl signal in the spectrum from 19-norpimara-8(14),15-dien-3-one(ABX signal in I with AB centeredat 5.15 T, X centered at 4.27 T with J AN.17.5, Jitx10.0, andJea2.5 Hz; in 19-norpimara-8(14,), 15-dien-3-one AB centeredat 5.0 T, X centered at 4.14 T with JAx17.5, Jux10.5 and JAB2.5 Hz).The carbonyl group of I was reduced with sodium borohydrideand the vinyl group reduced with hydrogen on palladiumcatalyst. The product was a mixture of two alcohols,the major product having spectra very similar to 4a-hydroxy-19-norisopimar-8 (14) -ene. The alcohol from the reductionwas dehydrated to a mixture of two hydrocarbons, one ofwhich (presumably 19-norisopimara-3,8(14)-diene) was chromatographicallyidentical with a hydrocarbon in a mixturepreviously obtained (Quon and Swan op. cit.) by lead tetraacetateoxidation of isopimar-8(14)-en-18-oic acid (formerlyknown by the trivial name of dihydrosandaracopimaric acid).Compound I should be tested for physiological activity becauseof its similarity to steroid structure.We thank Prof. T. Norin, Stockholm, for the gift of asample of 19-norpimara-8(14), 15-dien-3-one.—H. S. Fraserand E. P. Swan, Western Forest Products Laboratory, Vancouver,B.C.Isolation of a-Atlantone from the Heartwood Extractiveof Alpine Fir—Several years ago, the existence of two unknownsesquiterpene ketones in alpine fir [Abies lasiocarpa (Hook)Nutt.] was noted (Swan, Can. J. Chem. 45:1588-1590, 1967).We now report the identity of these two compounds as theZ- and E-isomers of a-atlantone, the latter is shown as I.ICompound I and its Z-isomer were isolated from thepetroleum ether extract of alpine fir heartwood by columnchromatography, followed by purification on silica gel G bypreparative layer chromatography (CH2Cl solvent). TheE-isomer is present in the largest amount and is the morestable, the Z-compound gives the E upon heating or prolongedstanding at room temperature. This behavior and the datafor the infrared (i.r.), proton magnetic resonance (p.m.r.)and mass spectra found by us were identical to data previouslyreported (Pande et al., Tetrahedron 841-844, 1971).However, we found slightly higher values for the ultravioletabsorption and optical rotation: Z-isomer, X max (e) 267(16,100), [a]n" +53°; E-isomer, A (e) 269 (26,800),[ajp" +108° versus 266 (10,210), rotation not given; 266(16,900), [a]e +1.2° given by Pande et al. We found thatthe parent ion m/e was 218.1706 for the high-resolution massspectrum (calculated for C15H220, 218.1670). Furthermore,oxidation of I with permanganate-periodate gave acetone; basecleavage of I gave the expected 4-(4'-methyl-3'-cyclohexenyl)-3-penten-2-one (Pfau, Helv. Chim. Acta 15, 1481-1483, 1931,et seq.). Finally, the synthesis of I has recently been reported(Crawford et al., J. Amer. Chem. Soc. 94:4298-4310, 1972).The i.r. and p.m.r. spectra of synthetic I E-isomer had identicalspectra to natural E-isomer.Since the work of Pande et a!. (op. cit.) was on the extractivesof Cedrus deodara and C. atlanticus, we obtainedthese species from the laboratory collection. Extraction ofwood from both species with benzene, followed by work-upgave crude E-I, identical chromatographically with I from A.lasiocarpa. The absence of Z-I was attributed to its lability andthe age of the Cedrus sp. samples.Acknowledgement: We thank Dr. R. J. Crawford, Proctorand Gamble Co., Cincinnati, Ohio, for the i.r. and p.m.r.spectra of a-atlantone, and Dr. R. M. Kellogg for the Cedrusdeodara and C. atlanticus samples.—H. S. Fraser and E. P.Swan, Western Products Laboratory, Vancouver, B.C.SILVICULTURERapid-Growing Precocious White Spruce Provenances.—Two white spruce [Picea glauca (Moench) Voss] provenanceswere found which grow rapidly and produce abundant conesprecociously. These provenances are potentially valuable inproducing genetically superior seed for silviculture, and inhybridizing with other provenances to combine their rapidgrowth and early and high seed productivity with other desirableproperties of pollen parents.First indications of precocity were observed in 1972 duringroutine inspection of the 12-year-old field trial of 54provenances. Two provenances had many trees bearing flowersand cones from the previous year, the eleventh year fromseed, while most other provenances had few if any treesbearing cones or flowers. Similar experiments (2 years older)planted at Chalk River and elsewhere (Table 1) allowed usto determine the extent that precocity is influenced by provenanceand by environment, and if precocity is associated withrate of height growth.The field experiments are described in previous publications(Nicholson, Can. For. Serv., Info. Rep. N-X-52 1970;Corriveau and Boudoux, Can. For. Serv. Info. Rep. Q-F-X-151971; Teich, Proc. 12th Meeting Comm. For. Tree BreedingCan. p. 95-100, 1971). From 25 to 54 provenances out of acollection of 62 provenances were planted at each site.At all locations (Table l) provenances varied significantly(P < .001) in frequency of cone-bearing trees. Provenance2442 (from Winchester, Ont., near Ottawa) had the highestfrequency in the two locations where it was planted, and was26% and 9% taller than the experimental averages at ChalkRiver (M) and Owen Sound, respectively. Provenance 244713

TABLE 1Frequencies of trees with cones, provenance heights, and experimental means(precocious and non-precocious provenances)North Pond, Nfld. Chalk River, Ont.D-1 Mtrees with height trees with height trees With heightProvenance cones-% % of mean cones-% % of mean cones-% % of mean2442 — —2447 3.9 117 19.7Experiment mean 0.6 100 3.91969 (92 cm) (116 cm) (72 cm)Height of tallestprovenance as 124 116 121percent ofexperiment meanOwen Sound, Ont.trees with heightcones-% % of mean33.0 109 66.9 126115 9.6 121 16.9 93100 1.5 100 12,2 100(51 cm)126(from near Grand Mere, P.Q.) had the second highest frequencyand was much taller than average in three out of fourexperiments. Flowering frequencies at Kapuskasing and GrandMere (spot checks of only this provenance) were 10% and2%, respectively.Precocious provenances were taller than average (Table1) and trees with cones were taller than trees without conesin the same plots:Height of Trees 1972with cones without conesLocation cm cmGrand Mere 192 167Chalk River M 222 180Chalk River D-1 272 241However, locations with the most height growth did not havethe most cone production.Cone counts, as distinct from the number of trees withcones, were not made, but it was evident that the higher thefrequency of trees with cones, the more cones there tendedto be on each tree.Late age at first flowering slows white spruce geneticimprovement, prolongs breeding and delays seed production.White spruce normally begins to flower between 10 and 20years of age from seed (Hoist, Recent Advances in Bot.2:1654-1658, 1959) and 6 years from grafting. This extendedperiod of juvenility makes a breeding program extending overmore than one generation impractical. The provenances discoveredin this study, flowering as early as in the eleventhseason, while only moderately precocious, are valuable because,as they grow rapidly, no generations are required to combineprecocity with rapid growth, and the precocity facilitates furtherimprovement.The rapid growing, precocious provenances have beenincorporated into the white spruce breeding program at thePetawawa Forest Experiment Station. The prospects are goodthat these early flowering selections may play a role in thedevelopment of highly productive white spruce strains.Individual trees of provenance 2447 have been selectedfor above-average growth and cone production, and hybridizedwith local plus trees for the establishment of pilot-scale seedlingseed orchards. If progeny tests confirm the apparentvalue of these selections, appreciable quantities of seed willsoon be available to increase white spruce productivity.We gratefully acknowledge Mr. Mark Hoist of this Station,who established the field experiments, and Dr. M. A. K.Khalil of the Newfoundland Forest Research Centre for providingthe data from North Pond, Newfoundland. — A. H.Teich and D. F. W. Pollard, Petawawa Forest ExperimentStation, Chalk River, Ont.The effect of Squirrel Damage on Norway Spruce (Piceaabies (L.) Karst.).—The red squirrel [Tamiasciurus hudsonicus(Erxleben)] damages Norway spruce by clipping the leadingshoot and branches of the first whorl or by consuming axillaryand lateral buds of this shoot. The injury is largely confinedto healthy trees with large, well developed buds; suppressedand unhealthy trees are avoided. At Petawawa squirrel damagein 1968 to a Norway spruce provenance was severe, particularlyin a provenance of German origin. It appeared thatthis damage could inhibit height growth and affect the analysisand interpretation of experimental results.Total height growth of trees in this German provenancewas sampled in two ways: (1) by measuring 20 uninjuredtrees, and (2) by measuring 20 non-classified trees, as a combinationof injured and uninjured trees. The sample contained12 injured and 8 uninjured trees, All samples were randomlyselected and measurements were repeated over a 3-year period,1968-70, at the end of each growing season. No further injurywas observed on the samples during "The 3-year period. Themean height of the uninjured sample increased from 217 to329 cm. (85.4-129.5 inches) in the 1968-70 period while themean height in the non-classified sample increased from 209to 286 cm. (82.3-112.6 inches).The analysis of variance (Table l) provides for onedegree of freedom between the two samples. The significancetest utilizes the within-sample mean square. It is seen thatdifferences in total height between the two samples were notTABLE 1Analysis fo variance of random samples taken from uninjured treesfrom a plot compared with all trees of the plot (injured and uninjured).Calculations based on 1968-1970 height and height incrementmeasurementsYear of observation Source DF Mean Square F Test1968 heights Among samples 1 680.62 0.35Within samples 38 1947.07Total 391969 heights Among samples 1 6125.62 2.99Within samples 38 2047.60Total 391970 heights Among samples 1 18062.50 6.53**Within samples 38 2765.20Total 391968-1970 height Among samples 1 11730.62Within samples 38 761.5515.40***Total 39Significance levels: * P = 0.05; *** P = 0.001significant in 1968 as expected, due to great variation in thatprovenance (height range of sample 190 cm., 74.8 inches);but they were significant (P = 0.05) in 1970. The differencesin 3-year height increment were very highly significant (P =0.001).The results indicate that squirrel injury can seriouslyaffect the analysis and interpretation of Norway spruce experiments.Decapitation of terminal shoots significantly inhibitssubsequent height growth in Norway spruce. It is unlikelythat damage is equally distributed, and the interpretation ofdata must take this into account.—Paul Viidik, PetawawaForest Experiment Station, Chalk River, Ont.14

SOILSComparisons of Four Methods of pH Determination inPeat Soils.-Four frequently used methods of pH determinationwere compared and their correlation examined. Over 70peat samples were collected from several locations in northernOntario. Determinations were made with a Zeromatic IIBeckman pH meter equipped with separate glass and referenceelectrodes and automatic temperature compensation. Wherenecessary, pastes were made by rewetting peat samples totheir liquid limit, i.e., the upper plastic limit as suggested byKrupskyi et al. (Soviet Soil Sci. 3:342-349, 1969).Values of pH determined in oven-dry peat (OP) plusdistilled H20 served as the independent variable Xi because, inthe course of the author's previous work, it was found to bethe least variable method. The dependent variables were pHY1values determined as follows:in (OP) plus N/100 CaCl2.2H20;Y2 in field-moist peat = (FU);Y3 = in peat squeezed by hand (SP) plus N/100CaCl22H20.Results are shown in Table 1 and regression lines inFig. l. The relative position of the regression lines demonstratesthat oven-drying and the addition of- extractants lowerthe pH value. The highest pH values were obtained in fieldmoistpeat and the lowest in oven-dry peat rewetted with N/ 100CaCl221-120.Analyses of covariance testing the differences in terms oflevels and slopes between linear regressions indicated no significantdifferences in slopes, but highly significant differences inlevels of regressions. Values of pH in oven-dry peat plusdistilled H20 are highly significantly different from pH values8.07.06.05.04.0,Y330. X3.0 4.0 5.0 6.0 7.0 8.0Figure l. Regression lines of pH values in oven-dry peat,N/100 CaCl2 •2H20 (Y1); hand-squeezed peat,N/100 CaCl 2 •2H20 (Y3); and field-moist peat, (Y2) onpH values in oven-dry peat + distilled H 20 (X).The lines cover only the population from pH 3.0 to8.0.'TABLE 1Results of inear regression analysesMethod Variable Mean Intercept Regr. Corr. SE, Max. Mm.Coeff. Coeff.ABROP + distilledH20X15.220 7.35 3.41OP + N/100CaC12-2H20 Y, 4.965 -0.40383 1.02850 0.98801 0.16254 7.14 3.00FP Y2 5.421 0.25481 0.98971 0.98889 0.15047 7A0 3.52SP + N/100CaC12-2H20 Y2 5.016 -0.30540 1.01946 0.98300 0.19260 7.27 3.05in field-moist peat. The pH values of (OP) and (SP) withN/ 100 CaCl 2:2H20 are not significantly different and couldbe safely combined. In comparison with field-moist peat ofpH 7.0, the regressions suggest the points of pH: (OP) and(SP) with N/100 CaCl2.2H20 6.6 and (OP) with distilledH20 6.8. With the calculated regression lines it is possibleto determine with high significance the pH values by the threeother methods from only one known pH value.-W. Stanek,Canadian Forestry Service, Great Lakes Forest ResearchCentre, Sault Ste. Marie, Ont.(Continued from back cover)Levitin, N. 1972. The coloring of mineral-stained maple.Wood Sci. 5(2) :87-94.Lindquist, 0. H. 1973. Notes on the biology of the oak leafminingsawfly, Profenusa lucifex (Hymenoptera :Tenthredinidae),in Ontario. Can. Entomol. 105-127-128.Little, C. H., G. M. Strunz, R. La France and J. M. Bonga.1972. Identification of abscisic acid in Abies balsamea.Phytochemistry 11:3535-3536.Mahendrappa, M. K. 1972. A technique for regulating oxygentension in a closed biological system. Plant Soil. 37:173-177.McMullen, L. H. and J. P. Skovsgaard. 1972. Seasonal historyof the balsam woolly aphid in coastal British Columbia,J. Entomol. Soc. Brit. Columbia. 69:33-40.Nanassy, A. J. 1972. Use of wide line NMR for measurementof moisture content in wood. Wood Sci. 5(3) :187-193.Nielsen, W. 1972. Agfacontour film for interpretation. Photogram.Eng. pp. 1099-1105 (November).Otvos, Imre S. and David G. Bryant. 1972. An extractionmethod for rapid sampling of eastern hemlock loopereggs, Lambdina fiscellaria fiscellaria (Lepidoptera: Geomertidae).Can. Entomol. 104:1511-1514.Page, G. 1971. Properties of some common Newfoundlandand forest soils and their relation to forest growth. Can.J. Forest Res. l:174-192.Parker, A. K. 1972. Artificial inoculation of Pinus radiatawith Scirrhia (Dothistroma) pini: Effect of relativehumidity and temperature on incubation. Phytopathology.62 : 1160-1164.Payandeh, Bijan. 1972. Projection of stumpage charge andharvesting costs for northern Ontario black spruce pulpwoodto the year 2010. For. Chron. 48 (December).Porter, A. W., M. L. El-Osta and D. J. Kusec. 1972. Predic-15

tion of failure of finger joints using acoustic emissions.For. Prod. J. 22(9): 74-82.Rogers, I. H. and D. Grierson. 1972. Extractives from grandfir [Abler Grandis (Doug].) Lindl.] bark. Wood Fiber4(1):33-37.Rogers, I. H. and J. F. Manville. 1972. Juvenile hormonemimics in conifers I. Isolation of (-)-cis-4-(P(r)-5'-dimethyl-3'-oxohexyl)-cyclohexane-1-carboxylicacid fromDouglas-fir wood. Can. J. Chem. 2380-2382.Salmon, M. 1972. Resistance moisture meter correction factorsfor western softwood species. For. Prod. J. 22(12):46-47.Sanders, C. J. 1972. Seasonal and daily activity patterns ofcarpenter ants (Camponotus spp.) in northwestern Ontario(Hymenoptera: Formicidae). Can Entomol. 104:1681-1687.Sanders, C. J. and G. S. Lucuik. 1972. Factors affecting callingby female eastern spruce budworm, Choristoneura fumiferana(Lepidoptera: Tortricidae). Can. Entomol. 104:1751-1762.Sayn-Wittgenstein, L. and A. H. Aldred. 1972. Tree size fromlarge-scale photos. Photogram. Eng. pp. 971-973.(October).Shaw, G. G. 1972. Importance of starches to spruce budworm(Lepidoptera: Tortricidae). Can. Entomol. 105:129-132.Smith, Stanley G. 1972. The chromosomes of some chrysomelidColeoptera: Diabroticites. Chromosomes Today,Vol. 3, pp. 197-207.Strung, G. M., M. Kakushima and M. A. Stillwell. 1972.Scytalidin: a new fungitoxic metabolite produced by aScytalidium species. J. Chem. Soc. Perkin Trans. I. pp.2280-2283.Turnock, W. J. 1972. Geographical and historical variabilityin population patterns and life systems of the larch sawfly(Hymenoptera: Tenthredinidae). Can. Entomol. 104:1883-1900 (1972).Tyrrell, David, S. S. Sohi and Mary A. Welton. 1972. Preservationof Entomophthora protoplasts in liquid nitrogen.Can. J. Microbiol. 18:1967-1968.Venkasteswaran, A. 1973. Effect of compression on electricalproperties of wood and cellulose. Wood Sci. 5(3):230-234.Von Althen, F. W. 1972. Eight-year results of an afforestationstudy. For. Chron. 48 (December).Wong, H. R. and H. E. Milliron. 1972. A Canadian speciesof Susana on western juniper (Hymenoptera :Tenthredinidae).Can. Entomol. 104:1025-1928.Yoshimoto, Carl M. 1972. A new species of the genusStemmatosteres (Encyrtidae: Chalcidoidea). Can. Entomol.104 : 1837-1839.16

ecent publicationsMARCH - APRILBeke, G. J. and Pawluk, S. 1971. The pedogenic significance of volcanic ash layers in thesoils of an east slope (Alberta) watershed basin. Can. J. Earth Sci. 8:664-675.Bohlen, I. C. 1972. Shear strength of high-temperature heat-treated Douglas-fir lumber laminatedwith phenol-resorcinol adhesives. For. Prod. J. 22(12):17-24.Bonga, J. M. 1972. Arceuthobium pusillum: moisture requirements for germination andradicle growth. Can. J. Bot. 50:2143-2147.Bousquet, D. W. 1972. Sawing pattern and bolt quality effects on yield and productivity fromyellow birch. For. Prod. J. 22(1l):39-48.Buckner, C. H. and J. M. Bergeron. 1971. The metabolic energy requirements of the redbackvole, Clethrionomys gapperi loringi (Bailey ) . Acta Theriologica XVIII ( 20 ) : 267-269.Cailleux, Andre et Jean-Claude Dionne. 1972. Concretions calcaires quaternaires dans leParc Des Laurentides, Quebec. Rev. Géogr. Montr. XXVI (4):361-379.Carroll, M. N. 1972. Measuring screw withdrawal with a torque wrench. For. Prod. J.22(8):42-46.Chow, S.-Z. and H. N. Mukai. 1972. Polymerization of phenolic resin at high vapor pressure.Wood Sci. 5(l):65-72.Desai, R. L. and M. R. Clarke. 1972. Simple wood surface treatment combats weathering andfungi. Can. For. Ind. (December).Dionne, Jean-Claude. 1972. Les basses terrasses de la region de Chicoutimi, Quebec. Rev.Géogr. Montr. XXVI (4): 407-420.Dionne, Jean-Claude and Andre Cailleux. 1972. Faulted calcareous concretions in pleistocenesediments. J. Geology 80:744-748.Eidt, D. C. and Margaret D. Cameron. 1972. Measuring growth and development in postdiapausespruce budworms (Lepidoptera: Tortricidae). Can. Entomol. 104:1901-1910.Evans, David. 1972. Alternate generations of gall cynipids (Hymenoptera:Cynipidae) ongarry oak. Can. Entomol. 104 : 1805-1818.Fast, P. G. and I. K. Morrison. 1972. The 8 Endotoxin of Bacillus thuringiensis IV. Theeffect of 8-endotoxin on ion regulation by midgut tissue of Bombyx mori larvae. I.Invertebr. 20:208-211.Fye, R. E. 1972. The effect of forest disturbances on populations of wasps and bees innorthwestern Ontario (Hymenoptera:Aculeata). Can Entomol. 104:1623-1633.Grisdale, Dale. 1972. An improved method for producing large numbers of second-instarspruce budworm larvae, Choristoneura fumiferana (Lepidoptera:Tortricidae). Can.Entomol. 104:1955-1957.Gross, H. L. 1972. Crown deterioration and reduced growth associated with seed productionby birch. Can. J. Bot. 50:2431-2437.Hallett, R. M. 1972. A method to analyze rough mill productivity. For. Prod. J. 22(11) :22-27.Hulme, M. A. and J. K. Shields. 1972. Effect of a primary fungal infection upon secondarycolonization of birch bolts. Material and Organismen 7 (3 ):177-188.Jeglum, J. K. 1973. Boreal forest wetlands near Candle Lake, central Saskatchewan. Musk-ox.No. 11 (January).Johnson, A. L. S., G. W. Wallis and R. E. Foster. 1972. Impact of root rot and other diseasesin young Douglas-fir plantations. For. Chron. Vol. 48 (December).Kusec, D. J. 1972. Twin-blade saw for precision machining of increment cores. Wood Fiber.4(l):44-49.(Continued on page 15)

i-monthlyresearchnotesTestis-sampling technique for holo- and hemi-metabolus insects.Susceptibility of two birches to the birch casebearer.Nematicide trials for corky root disease.Association of soil properties with corky root disease.Chemotherapy trials on sweetfern blister rust.Effects of phosphatic fertilizers on spruce seedlings.Errata.Vol. 29, No. 3, MAY-JUNE, 1973.I+Environment EnvironnementCanada CanadaForestry ServiceService des forêts

i-monthlyresearch notes"A selection of notes on current research conducted bythe Canadian Forestry Service and published under theauthority of the Minister of the Department of theEnvironment. A French edition is published underthe title of Revue Bimestrielle de Recherches".ENTOMOLOGYA Testis-sampling Technique for Hobo- and Hemi-metabolousInsects.—Studies of endophenotypic variation in insects –within individuals or populations – generally involve the removalof the reproductive organs and ensuing death of thedonor. This technique allows only a static analysis of eventsthat have taken place during meiosis and requires extrapolationto assess their future role either in natural populations or inlaboratory matings involving sibs of the dissected insects. Unlikeexophenotypes, we have no direct method of following chromosomalmutations through several generations.With the possible involvement of chromosomal mechanismsin the genetic control of populations, it has becomenecessary to find a direct method of meiotic assay which doesnot hinder the reproductive capacity of the insect and permitsit to be used for breeding after the analysis. This would allowunambiguous observation of the behavior and fate of suchmeiotic abnormalities as aneuploidy, translocations, and inversions,both in parent and offspring.Such a sampling method has been devised for two insects,the spruce budworm [Choristoneura fumiferana (Clem.)] andthe desert locust [Schistocerca gregaria Forsk.]. Because oftheir very different patterns of metamorphosis, the techniqueemployed is different for each insect.(a) Schistocera gregariaAdult males were labelled and coded immediately afterthe final ecdysis and were subsequently sampled at a knownage. After the insect was anaesthetized with CO 2, the testiswas exposed by making a lateral incision along the lengthof the fourth and fifth abdominal pleurites, 10-15 follicleswere teased away from the testis, and then removed by cuttingclose to their base. These samples were fixed in 3:1 alcoholaceticacid and refrigerated before chromosomal assay. Upto 30 insects could be sampled per hour.The incision was sealed with low melting point dentalwax. The open structure of the testis with 70-90 folliclesallowed at least two further samples to be taken. Chromosomeassay can be completed before the insect has attainedsexual maturity (as determined by pigmenentation patterns).Males that have been subjected to this technique are stillfertile and, when involved in matings, their female partnersproduce normal quantities of fertile eggs. This technique hasfacilitated a direct disruptive selection program for high andlow chiasma frequency and an analysis of temporal variationin chiasma frequency at different temperature regimes withinthe individual. Over 400 males have been sampled in thismanner and so far none have died within 4 weeks of theoperation.(b) Choristoneura fumiferanaIn this species, the production of secondary spermatocytesis at peak in the fifth larval instar. The paired testes arevisible through the integument as dark oval bodies. UnlikeSchistocerca, the four testicular follicles are enclosed by atwo-layered testis wall and consequently only whole testes canbe successfully removed.Fifth-instar larvae were anaesthetized with diethyl ether.(In this species, CO2 cannot be used since it causes the bodycavity to swell and any incision results in a massive, usuallylethal, loss of haemolymph.) A dorso-lateral incision wasmade above the position of the testis as soon as spiracularmovement had ceased. The turgidity of the body cavity pushedthe testis partially through the incision and facilitated testisremoval with either fine forceps or by suction using a microsyringe,after excision of the vas deferens. Contrary to Retnakaran(Annal. Entomol. Soc. Amer. 63: 851-859, 1970), wehave found that the vasa deferentia are present in the fifthinstarlarva and can be traced from the posterior tip of thetestis to the ectodermal reproductive anlage on the last abdominalsegment. This has precluded the possibility of testistransplants between Choristoneura species.After testis removal, the incision was left unsealed since,upon recovery from the anaesthetic, there was no excessiveloss of haemolymph. The larvae were returned to feedingcups to complete larval development and pupation. The emergingadults were mated to females in single-pair mating cages.Mating success and egg hatchability were not affected byremoval of a testis from the male parent. In this species,the operation is more difficult because of the delicate natureof the donor and post-operative mortality was 25%.This direct sampling technique can reduce the rearingprogram needed to assess the meiotic effects of physicochemicaltreatments or the behavior of supernumerary chromosomematerial in laboratory-reared populations and theirfate in future generation.—D. D. Shaw and M. G. Morgan,Maritimes Forest Research Centre, Fredericton, N.B.Differences between two Species of Birch in Attack andSusceptibility to Defoliation by the Birch Casebearer.—Thebirch. casebearer [Coleophora fuscedinella Zeller] was discoveredin Newfoundland in 1953, and by 1971 it had become themost important pest of birch throughout the Island. Adultsof the casebearer emerge in July and lay eggs on the undersideof leaves. The insects overwinter as a second-instar larvae inthe tree crown, attached to branch crotches or to the base ofbuds. Larvae begin to feed in the spring when the buds areflushing, and continue to feed till pupation in mid-June. Larvaefeed by attaching their cases to the leaf and mining the leafas far as they can reach without detaching themselves fromthe cases. After a larva has consumed all the food it canreach, it detaches its case and moves to a different area ofthe leaf to feed. This feeding habit creates somewhat reactangularbrown patches on the leaf. Feeding causes defoliationby destroying the photosynthetic materials of the leaf. Feedingby large numbers of larvae causes individual leaves and ultimatelythe whole tree, to appear brown.Preliminary surveys indicated differences in the intensityof defoliation between Betula papyrifera Marsh. [white birch]and Betula cordifolia Regel [mountain white birch]. Both occurin Newfoundland (Brittain and Grant, Can. Field-Natur. 81:251-262, 1967), and both are common in western and centralNewfoundland. This report presents data that quantifies thedifference in birch casebearer abundance, as reflected by intensityof defoliation, number of eggs laid, and number of overwinteringlarvae.Data were collected from 10 trees of each species, 15-25ft (4.6-7.6 m) in height in a stand near Cormack in westernNewfoundland. Starting 100 ft (30.5 m) from the stand edge,the first 10 trees encountered of each species in a 50-ft (15.2m) wide strip were chosen; but only one tree per clump.Randomly selected leaves from the peripheral 10 inches (25.4cm) at mid crown of each tree were used to obtain defoliationestimates (20 leaves), and number of eggs per leaf (10 leaves).The number of overwintering larvae was expressed as theaverage number on four branch crotches in the fall. Branchcrotches were located near the stem, and one each per quarterof crown height.Results of the study are summarized in Table l. Estimateddefoliation on B. papyrifera was about six times more severe17

than for B. cordifolia. The feeding pattern of individual larvaeon B. papyrifera consisted of many large feeding areas whichtended to be contiguous, on B. cordifolia large feeding areaswere scarce and tended to be scattered. This difference in feedingpattern caused severely attacked B. cordifolia trees toappear mottled, quite different from the uniform brown appearanceof severely attacked B. papyrifera.The number of eggs per leaf and number of overwinteringlarvae per branch crotch on B. papyrifera was about two andone-half times greater than on B. cordifolia. Means werecompared with Student's t test, and both differed significantlyat the l% level.TABLE 1Difference in defoliation and birch casebearer numbers betweenBetula payrifera and B. cordifoliaB. papyriferaB. cordifoliaAvg S.D. Range Avg S.D. RangePercent defoliation 29 – 11-55 5 – 1-7No. eggs per leaf 16.7 10.4 0-52, 6.1 4.8 0-19No. larvae in branchcrotches 27.7 19.6 5-94 11.9 7.9 3-51These differences in intensity of defoliation and insectnumbers indicates that B. cordifolia is much less likely to bedamaged by the birch casebearer. The difference in insectnumbers indicates that birch trees must be correctly identifiedwhen sampling to obtain estimates of casebearer abundanceor estimates of potential defoliation.—A. G. Raske, NewfoundlandForest Research Centre, St. John's, Nfld.PATHOLOGYCorky Root Disease of Douglas-fir Seedlings: Post-PlantNematicide Trials to Control Xiphinema bakeri.—Since 1963,corky root disease (Bloomberg, Bi-Mon. Res. Notes 24:8, 1968)has ruined about l.5 million Douglas-fir [Pseudotsuga menziesii(Mirb.)] Franco seedlings in coastal British Columbiaforest nurseries. The nematode Xiphinema bakeri Williams isthe primary pathogen (Bloomberg and Sutherland, Ann. Appl.Biol. 69:265-276, 1971). Corky root can be controlled bypre-plant application of nematicides (Bloomberg and Orchard,Ann. Appl. Biol. 64:239-244, 1969) or by bare fallowing accompaniedby frequent disking of infested areas during thehot, dry, late summer - early fall period.Although pre-plant controls are satisfactory, post-plantones are needed to eradicate the nematode on seedbed seedlingsand transplants. Generally, nematicides are injected ordrenched into the soil. Recently attention has focused on systemicmaterials that can be applied to plant foliage and thentranslocated to the roots to act as nematicides. The objectiveof the two experiments reported herein was to determine theusefulness of two soil-applied nematicides (Diazinon andNemagon) and a promising systemic (Vydate) (Radewald etal., Plant Dis. Rep. 54: 187-190, 1970; Birchfield, Plant Dis.Rep. 55: 362-365, 1971; Abawi and Mai, Plant Dis. Rep. 55:617-620, 1971; Miller, Plant Dis. Rep. 56: 255, 1972) forpost-plant of control X. bakeri on Douglas-fir.Experiment 1In March 1972, a sandy loam, X. bakeri-infested soil fromthe Campbell River nursery was thoroughly mixed, and putinto plywood boxes (each 34 x 8 x 8 inch; 86.4 x 20.3 x 20.3cm) lined with plastic sheeting. Thirty, 1-yr-old corky-rootdiseasedDouglas-fir from Campbell were selected for uniformityof size and disease severity and transplanted into eachbox with three equally-spaced rows of 10 seedlings each. Thenematicides and their equivalent application rates (formulatedas water-based emulsions) were: a) Diazinon® [0,0-diethyl0-20 isopropyl-4-methyl-6-pyrimidyl phosphorothioate] at 35,50 or 75 lb. a.i. per 120 Imp gal (546 1) of water per acre(39, 56 and 84 kg per hectare) applied as a soil drench; b)Nemago® (1,2-dibromo-3-chloropropane) at 20, 40 or 60 lb.a.i. per 600 Imp gal (2,728 l) of water per acre (22, 45 and68 kg per hectare) dribbled into 2.5 inches (6.4 cm) deep soiltrenches on either side of each seedling row; after treatment,the trenches were filled with soil, and c) Vydate® [S-methyl1-(dimethyl carbamoyl)-N-[ (methyl carbamoyl) oxyl] thioformimidate]at 2, 4 or 6 lb. a.i. per 100 Imp gal (455 l) of waterper acre (2.2, 4.5 and 6.7 kg per hectare) sprayed onto seedlingshoots and soil surface. The nematicides, one per box, wereapplied 1 week after transplanting when the seedlings werestill dormant. Vydate was also applied, 35 days after transplanting,to other seedlings that had broken dormancy. Nowater was applied to Vydate-treated foliage for 5 days aftertreatment; otherwise, all seedlings were watered as needed andgreenhouse temperatures ranged from 98 to 64 F (41 to 11 C).Each treatment and control (distilled water) was replicatedfour times in a completely random design.From 21 Aug to 28 Sept (145 to 183 days after transplanting),the seedlings were removed from the soil, the nematodeswere obtained from the roots (Bloomberg et al., Bi-Mon.Res. Notes 26: 14-15, 1970), the second year's shoot growthwas measured, and fresh weights were obtained for it and theroots. The data were transformed (natural log) for analysisof variance, and treatment means were compared, using theNewman-Keuls test (Miller, Simultaneous statistical inference,McGraw-Hill, New York).The results showed that Nemagon was the only nematicidethat produced a significant (P .05) treatment effect;consequently only results for the Nemagon treatment are givenin Table 1. Numbers of X. bakeri/g of root decreased asNemagon rates increased up to 40 lb. per acre, but there wasno significant (P ---- .01) difference between the 40 and 60 lb.per acre rates (Table 1). Nemagon also caused a reductionin root weight, i.e., it was apparently phytotoxic, whereas shootweight and length were not affected. Although Nemagon hasbeen reported (Ferris and Leiser, Plant Dis. Rep. 49: 69-71,1965) to be phytotoxic to unthrifty, field-grown spruce, weobserved no phytotoxic symptoms such as chlorosis or deathon Douglas-fir seedlings.TABLE 1Effect of Nemagon (Experiment 1) and Vydate (Experiment 2) onnumbers of Xiphinema bakeri nematodes and seedling growth aMaterial and No. nematodesapplication rate /g fresh root(lb. a.i./acre)Fresh wt Second yr Second yr shootroots (g) shoot wt (g) length (cm)Nemagon0 33a 1.8b 0.36a 38a20 17b 1.7ab 0.49a 44a40 7c 1.5a 0.69a 51a60 7c 1.6ab 0.51a 46aVydateHealthy seedlings0 49b 2.6a 0.38ab 33b2 27a 2.4a 0.40ab 42a4 23a 2.5a 0.44a 42a6 35ab 2.0b 0.37b 39aDiseased seedlings0 62b 1.5b 0.27b 35b2 37a 1.9a 0.36a 44a4 42a 1.9a 0.34a 41a6 52ab 1.2c 0.29b 40aValues for Experiment 1 are means of 4 replicates, those for Experiment2 are means of 30 replicates; means followed by a letter incommon do not differ significantly (P = .01) for nematodes per g ofroot in the Nemagon treatment, P c .05 for all other differences).Experiment 2On 12 April 1972, 1-yr-old corky root diseased (fromCampbell River) and healthy (container grown) Douglas-firwere transplanted, one seedling per 6 inches (15 cm) pot, into18

X. bakeri infested Campbell River soil. After breaking dormancy(8 May), each seedling shoot was immersed three consecutivetimes into a Vydate solution and the seedling laidhorizontally until dry. Seedlings were then arranged in a completelyrandom design on a greenhouse bench, with each treatment(2, 4 or 6 lb. a.i. per 100 Imp gal of water per acre)and control (distilled water) replicated 30 times. Seedlingswere not watered for 5 days after treatment; thereafter, waterwas applied only to the soil surface. The experiment was evaluated(1- 12 Oct), using the same techniques as describedfor Experiment 1, except no data transformation was neededfor the analysis of variance.Foliage application of Vydate showed that (disregardingapplication rate) there was no overall difference (Pbetween the number of X. bakeri nematodes on roots ofhealthy (34 per g) and diseased (49 per g) seedlings, i.e.,Vydate nematode control was as good on diseased as onhealthy plants. However, Vydate did reduce X. bakeri populationson both diseased and healthy seedlings (Table 1),especially at the 2 and 4 lb. application rates. The 6 lb. rate ofVydate reduced root weight of diseased and healthy seedlings.There was no clear-cut trend between seedling shoot weightand Vydate concentration, but the nematicide treatment didincrease shoot length. No seedlings died or exhibited anyshoot symptoms of phytotoxicity. We do not know whyVydate gave some control of X. bakeri here, but not in thefirst experiment.Recent evidence (Sutherland and Sluggett, 1972, unpublished)indicates that corky root development depends uponthe combined effects of X. bakeri root feeding and low soilfertility. Future nematicide tests should determine the valueof applying both a nematicide and fertilizer to disease infestednursery areas. Our results indicate that both Nemagon, whichhas a low mammalian toxicity, and Vydate should be includedin such trials.-S. Ilnytzky and Jack R. Sutherland, PacificForest Research Centre, Victoria, B.C.Association of Some Physical and Chemical Properties ofNursery Soils with Corky Root Disease.-The nematodeXiphinema bakeri Williams is the "primary" pathogen of corkyroot disease because its feeding precedes root invasion by thesoil-borne fungi Cylindrocarpon destructans (Zinnsm.) Schaltenand Fusarium oxysporum Schletcht. (Bloomberg and Sutherland,Ann. Appl. Biol. 69: 265-276, 1971). Sutherland andSluggett (Can. J. Forest Res., in press) found diseased seedlingsand soil from a disease-infested area in the CampbellRiver nursery contained statistically lower amounts of severalnutrients than their healthy counterparts, which suggested thatdisease development depends upon the combined effects ofnematode feeding and low soil fertility. Related to this latterfactor is the field observation that the disease prevails on thesandiest soils within infested fields. Because the implication ofsoil fertility had been studied only at the Campbell River nursery,the present study was made to determine some physicaland chemical properties of Green Timbers and Haney (AlouetteLake) nursery soils where the disease has also occurred.In August 1972, 10 randomly selected soil cores, taken toa 6-inches (15 cm) depth, were collected and bulked fromadjacent 50 x 50 ft (15.2 x 15.2 m) plots with and withoutcorky root disease. When sampled, Haney field 1 and GreenTimbers field 4 were in bare fallow and Green timbers field 7was in 2-0 Douglas-fir. The 4-5 lb. (1-5-2.0 kg) samples wereair dried, sieved (10 mm sieve) and passed through a samplesplitter, after which subsamples were analyzed for: texture(Bouyoucos, Soil Sci. 23: 343-353, 1927); total N by micro-Kjeldahl; P by acid fluoride extraction; exchangeable K, Mg,and Ca by ammonium acetate extraction; pH and conductance(soluble salts) by saturated soil paste; cation exchange capacity(CEC) by ammonium saturation; and total organic carbonby Leco carbon analyzer. These methods use the standard proceduresfor this laboratory (McMullan, Can. For. Serv. Inf.Rept. BC-X-50, 1971; McMullan, Can. For. Serv. Inf. Rept.BC-X-67, 1972).Table 1 shows that corky root soils contained more sandand less silt and clay than non-corky root soils. The resultsalso confirm our earlier Campbell River observation (Sutherlandand Sluggett, Can. J. Forest Res., in press) that corkyroot soils are less fertile than disease free soils, e.g. they containedless N, K, Mg, and Ca and had lower CEC and carboncontent values than non-corky root soils. Phosphorus andacidity (pH) levels of the two soils were similar and the conductancereading indicated that neither soil contained harmfulamounts, 4000 to 8000 micromhos/cm for most plants, ofsoluble salts (Bower and Wilcox, pp. 933-940, in Methods ofSoil Analysis, part 2, C. A. Black, Ed., Vol. 9 of Agron. Mono.,1965). The lower fertility levels of corky root soils areprobably attributable to their lower clay and organic carboncontents, two factors influencing CEC (Lyon et al. The natureand properties of soils, MacMillan, New York, 1952). Theirhigher sand content likely results in greater available porespace, which favors nematode population build-up. We donot know why these areas of sandy soil occur, but perhapsthey are exposed areas of interglacial sand (Fyles, In Dayet al., Rep. No. 6, B.C. Soil Surv., 1959).TABLE 1Some physical and chemical properties of soil from corky root andnon-corky root nursery areas'Non-corkyroot areasCorky rootareasAdequatenutrientlevelsbPhysical propertiesSand, % 58 ± 3.5 67 3.3Silt, % 14 2.1 9i- 0.9Clay, % 28± 1.7 23 2.4Chemical PropertiesN (total), % .59± 0.20 .36± 0.05 .20P, ppm 14 ± 5.4 15 - 3.7 100K, ppm 86± 7.3 51±14.2 78Mg, ppm 55 ± 25.9 28 - 8.5 170Ca, ppm 625 285 497 207 1000pH 5.7 -±: 0.4 5.5 0.3conductance° 637 115 425 -± 77CECd 44 5.3 36 -± 1.2Carbon (totalorganic), %4.3 + 1.3 3.2 0.4a Value are means of three samples, ± SE of the mean.b For Douglas-fir nursery seedlings (van den Driessche, B.C. For. Serv.Res. Note No. 48, 1969).Micromhos/cm.d Cation exchange capacity = meq/100 g air-dry soil.The adequate nutrient level values (Table l) indicate thatN is adequate in both corky root and disease free soils whileP, Mg, and Ca are deficient in both soils and K is adequatein "healthy" but not corky root soils. Such comparisons maybe misleading because they do not consider the minimumnutrient levels at which seedlings can grow and still not exhibitdeficiency symptoms. For example, 170 ppm Mg is adequatefor seedling growth and even a 55 ppm in non-corky rootsoils (Table l) growth may be uneffected, but the low (28ppm) Mg levels in corky root soils may be critical, especiallywhen seedlings are subjected to the additional stress of X.bakeri nematode root feeding.Because past cultural and cropping practices have variedwidely within and among nurseries, it may not be possibleto pin-point specific nutrient deficiencies for corky root soils.Probably their only common characteristics are that they aresandier and less fertile than their "healthy" counterparts. Fallowingincreases the organic matter and nutrient content ofcorky root soils would help seedlings offset the effects ofX. bakeri feeding.-Jack R. Sutherland, L. J. Sluggett, andW. Lock, Pacific Forest Research Centre, Victoria, B.C.19

Chemotherapy Trials on Sweetfern Blister Rust Cankers.-Despite early reports of successful control of white pine blisterrust [Cronartium ribicola J. C. Fischer] on western white pine[Pinus monticola Dougl.] with the antibiotics cycloheximideand phytoactin (Moss et al. J. Forest. 38: 691-695, 1960),later results were variable and discouraging (Dimond, J. Forest,64: 379-382, 1966) and even the best levels of control weretoo low for an effective control program. Similar chemicaltests have not been reported for sweetfern blister rust incitedby Cronartium comptoniae Arth. This is the major stem rustfungus attacking hard pines in the Maritime Provinces (VanSickle, Plant Dis. Rep. 53: 369-371, 1969). With most stemrusts, such as C. ribicola, once the aeciospores are released,the bark cracks, the cambium and underlying wood die, andthe tree is eventually girdled. With C. comptoniae, however,the cambium is not killed even after several years of infection,rather it produces an abnormal xylem in characteristic wavypatterns. Thus, testing of chemicals to control sweetfernblister rust cankers seemed justified, as even trees with mostof their circumference infected might revert to normal growthif the fungus could be inhibited.On 11 June 1969, when aecia were obvious, 60 infectedlodge-pole pine [Pinta contorta Dougl.] averaging 4.2 in.(10.7 cm) dbh were selected in a 20-year-old plantation nearLawrencetown, N.S. All trees were dominants or codominantswith a bole canker within 6 ft (182.9 cm) of the ground(average canker length, 2.7 ft (82.3 cm); range, 1.1 - 6.0 ft(33.5 - 182.9 cm); average proportion of bole circumferenceaffected, 0.6; range, 0.1 - 1.0). Six groups of trees were randomlyselected and each group given one of six treatmentsapplied on 16 July 1969: (l) control - five trees were sprayedwith water only, five received no treatment; (2) 5.0% sodiumarsenite solution in water; (3) number 1 stove oil; (4) phytoactinL-440 at 200 ppm in stove oil; (5) 11% dimethyl sulfoxide(DMSO) in water; and (6) cryptosporiopsin (Stillwellet al. Can. J. Microbiol. 15: 501-507, 1969) at 400 ppm inDMSO and water. Solutions were applied to the point ofrun-off to the basal 6 ft of each bole from a hand-operatedgarden-type sprayer (except treatment 2 which was brushedon to prevent drift). Trees received an average of 1.6 qtImp (1.8 1) of solution in treatments 2, 3, and 4, and 0.25qt (0.3 l) in treatments 5 and 6. All trees were reexaminedin 1970, 1971, and 1972 during the period of peak aecia production(about mid-June). The active area of each canker wasestimated by measuring the lineal extent of aecia on each ofthe cardinal faces of the tree. To compare treatments, thetotal for each canker for each year was expressed as a proportionof the corresponding 1969 measurement before treatment.Even 1 year after treatment, considerable tree mortalityhad occurred (Table 1). Most trees were of low vigor, havingbeen infected for 10 15 years and subsequently attacked bywood-boring beetles, and some chemicals were phytotoxic atthe concentrations tested. Treatment with 5% sodium arsenitekilled all 10 trees, which was unexpected as Brown and Rowan(U.S. Dep. Agr., Forest Serv. Res. Note SE-75, 1967) appliedhigher concentrations to southern pines without phytotoxicity.1970Aecia production" %treeTreatment Mean Range/ mortalityDSMO + Water 0.69 0-1.36 0DMSO + Water -I-Cryptosporiopsin 0.74 0.15-1.32 0Fuel 011 0 0 30Fuel 011 + Phytoactin 0.01 0-0.05 30Water only 1.43 0.92-2.23 20None 0.80 0.50-1.17 0Reduced sporulation was evident, but it was insufficientfor effective control. Although the sample size was too smallfor meaningful statistical analysis, the range of values obtainedand the differences between means are useful in comparingtreatments (Table 1). A substantial decrease in aecia productionoccurred after treatment with fuel oil and phytoactin,and a slight reduction followed spraying with cryptosporiopsinand DMSO, but in no case did the antibiotics result in asignificant improvement over the carrier alone (t-test, p 0.05).No obvious explanation can be given for the apparentstimulation of aecia production during the first 2 years afterthe single application of water (Table 1). Perhaps it enhancedthe cross-fertilization of the pycnia. Further study of thisphenomena is required to determine any cause-effect relationshipor its possible role in the initiation of epidemics.Results indicate little promise of an economical eradicationof sweetfern blister rust cankers form severely infectedtrees using the chemicals tested. Greater benefit, however,may arise from treating younger, recently infected trees, withlower concentrations of solvents but higher concentrations ofcryptosporiopsin which showed the most promise and leastphytotoxicity. Two or more applications made in consecutiveyears may also enhance the degree of control.I thank P-L Biochemicals Inc., Milwaukee, Wisc., U.S.A.for donating the phytoactin and M. A. Stillwell of this ResearchCenter for the cryptosporiopsin.-G. A. Van Sickle, MaritimesForest Research Centre, Fredericton, N.B.SILVICULTUREEffects of Different Phosphatic Fertilizers on the Growthof Spruce Seedlings in a Greenhouse.-Commercially availablephosphatic fertilizers differ widely in their physical and chemicalproperties. However, in Newfoundland few attempts havebeen made to determine their effects on the growth of trees.In 1968, the Newfoundland Forest Research Centre initiatedgreenhouse studies to obtain information on the relative effectivenessof a number of phosphatic fertilizers when applied totwo common Newfoundland forest soils. Results are presentedbelow.Bulk soil samples, including organic and mineral materials,were collected from the upper 9 inches (5.1 cm) of theprofile beneath a semi-mature black spruce [Picea mariana(Mill.) B.S.P.] stand near Badger in central Newfoundlandand a semi-mature balsam fir [Abies balsamea (L.) Mill.]stand near Deer Lake in western Newfoundland. Each soilsample was air-dried, passed through a 2 mm sieve and thoroughlymixed. Fifteen six-inch plastic containers were filledwith soil from each of the two stands. Nitrogen as ammoniumnitrate and potassium as potassium chloride (reagent grade)were applied in powder form to all containers at rates of 300and 200 ppm respectively. Four commercial grade phosphaticfertilizers, basic slag, rock phosphate, potassium metaphosphate,and ordinary superphosphate were each applied inpowder form to 6 containers (3 of each soil)at a rate of 100ppm of phosphorus. The particle size of basic slag and rockphosphate was -100 mesh and of potassium metaphosphate andTABLE 1Aecia production by Cronartium comptoniae on lodgepole pine after treatment in 19691971Aecia production1972Aecia production%treemortalityMean Range%treemortality Mean Range0.90 0.13-1.46 20 0.54 0.28-1.33 200.69 0-1.36 10 0.46 0-1.00 200.02 0-0.10 50 0.03 0-0.14 600.04 0-0.23 50 0.10 0-0.35 601.56 1.00-2.38 20 0.87 0.42-1.31 200.98 0.41-1.59 0 0.68 0-1.21 0• Expressed as a proportion of the corresponding measurement for each canker taken before treatment,▪ Range of individual measures from each 4 10 trees (only measurements from living trees were averaged).20

ordinary superphosphate -60 mesh. Six containers received nophosphorus and served as controls. Soil and fertilizer in eachpot were thoroughly mixed.Four sitka spruce seedlings (2 + 0) were planted in eachof the containers of soil from Badger and two black spruceseedlings (2 + 2) in each of the containers of soil from DeerLake. Seedlings were grown in a greenhouse at 25 C untilnoticeable differences in growth were observed between treatments.This required a period of 18 months for the sitkaspruce and 12 months for the black spruce seedlings. Afterharvesting, the aerial parts of the seedlings were oven-driedat 70 C, weighed, and ground in a small Wiley mill. Totalphosphorus in the ground samples was determined by theDickman and Bray method (Ind. Eng. Chem., Anal. Ed.12:665-668, 1940). Data on the analysis of the two soils aregiven in Table l. Data for dry matter production and phosphorusuptake by sitka spruce and black spruce seedlings foreach soil and each fertilizer treatment are presented in Table 2.TABLE 1Analysis of soil samples from upper 9 inches (5.1 cm)prior to fertilizer applicationOrganic Cation Available nutrientsSoil matter C/N exchange(lb./acre)pH % ratio capacity N P K Ca Mg(meq/100g)Badger' 5.1 4.9 19.4 8.9 15.6 T' 96.0 64.0 52.0Deer Lake 2 4.5 3.5 18.7 9.8 15.6 5.0 104.0 88.0 50.4Mini humo-ferric podzol, sandy loam.2 Orthic humo-ferric podzol. sandy loam.8 Trace.TABLE 2Effects of four different sources of phosphorus on dry matter productionand phosphorus uptake by sitka spruce and black spruce seedlingsgrowing on two types of soils.'Sitka spruce onMini humo-ferric podzolDry matter P uptake(g/pot) (mg/pot)Black spruce onOrthic humo-ferric podzolDry matter P uptake(g/pot) (mg/pot)Treatment1. Control 2.7a2 1.5 3.9a 5.3a2. Basic slag 2.9a 2.2 7.6b 9.7a3. Rock phosphate 3.5a 2A 10.2c 8.8a4. Potassium metaphosphate4.8b 4.9 13.9d 17.4b5. Ordinary6.3c 5.2 13.4d 19.4bsuperphosphateL.S.D. at 5% level 1.3 N.S.3 2.5 7.31 The data are based on the means of three replicates." a, b, c and d - values followed by the same letter do not differ significantlyat 5% level of probability.N.S. - No significant difference.The superphosphate and potassium metaphosphate treatmentsproduced significantly more sitka spruce dry matter thanthe basic slag, rock phosphate, and control treatments on amoderately acid mini humo-ferric podzol (Table 2). Superphosphatewas superior to potassium metaphosphate. Thisresult is attributed to high water solubility of the phosphoruspresent in superphosphate and its availability to the sitka spruceseedlings. In addition the seedlings may have responded tosulphur which is present in superphosphate as calcium sulphate.Phosphorus in rock phosphate and basic slag is insoluble inwater, and thus unavailable to seedlings. Benzian (Proc. Fert.Soc. Lond. 94: 3-35, 1966) tested three phosphate fertilizerson moderately acid soils under nursery conditions with similarresults. Phosphorus uptake by sitka spruce showed a similarpattern to that observed for dry matter production, but alldifferences were non-significant.Superphosphate and potassium metaphosphate treatmentsproduced significantly more black spruce dry matter and greateruptake of phosphorus than the rock phosphate, basic slag andcontrol treatments on a strongly acid orthic humo-ferric podzolsoil. Increased availability of phosphorus from superphosphateresults from its high water solubility; the availability of phosphorusfrom potassium metaphosphate is a result of greaterdissolution caused by hydrolysis and strong acidity in the soil.Rock phosphate and basic slag also significantly increased drymatter production over the control, although not to the sameextent as did superphosphate and potassium meta-phosphate.This result is also attributed to the highly acidic nature ofthe soil which caused some dissolution of phosphorus fromthese two fertilizers.This experiment suggests that superphosphate and potassiummetaphosphate may be the best types of fertilizer foruse on the soils tested. However, before these fertilizers canbe recommended for operational use, their long term effectivenessin comparison with rock phosphate and basic slag needsto be determined under field conditions.-N. D. Bhure, NewfoundlandForest Research Centre, St. John's, Nfld.Errata: Vol. 28, No. 6p 40, col 2, line 17 under Silviculture; should be (1.6 cm).p 40, col 2, line 18 under Silviculture; should be (2.0 cm).p 40, col 2, line 19 under Silviculture; should be (2.1 -3.l m).p 41, col l, line 1 under Table 1; should be (7.6 cm).p 41, col l, line 6 under Table l; should be (58.4 x 38.l x10.6 cm).(Continud from back cover)Mullick, D. B., and G. D. Jensen. 1973. Cryofixation revealsuniqueness of reddish-purple sequent periderm and equivalencebetween brown first and brown sequent peridermsof three conifers. Can. J. Bot. 51:135-143.Myronuk, R. S. 1972. A semi-automatic veneer-thickness measuringsystem. For. Prod. J. 22(4):32-34.Nanassy, A. J. 1972. Measurement of free-radical concentrationin solids by electron paramagnetic resonance comparisontechnique. J. Applied Polymer Sci. 16:2577-2582.Newnham, R. M. 1973. Process control in forest harvesting.For. Chiron. 49 (February).Neumann, P., and M. Hubbes. 1972. Factors in Abies balsamearesponsible for coremia formation of Ceratocystispiceae. Europ. J. For. Pathol. 2(4):215-229.Ofosu-Asiedu, A., and Roger S. Smith. 1973. Some factorsaffecting wood degradation by thermophilic and thermotolerantfungi. Mycologia. LXV: 87-98.Ofosu-Asiedu, A., and Roger S. Smith. 1973. Degradation ofthree softwoods by thermophilic and thermotolerant fungi.Mycologia LXV:240-244.Page, G. 1972. The occurrence and growth of trembling aspenin Newfoundland. Dep. Environ., Can. For. Serv. Pub.1314. 15 p.Palka, L. C., and B. Holmes. 1973. Tangential failure of smallwood cantilevered beams with square notches. Wood Sci.5(3): 172-180.Payandeh, Bijan. 1973. Plonski's yield tables formulated. Dep.Environ. Can. For. Serv. Pub. 1318. 13 p.Pollett, Frederick C. 1972. Classification of peatlands in Newfoundland.Proc. 4th Internat. Peat Congr. I-IV. Helsinki.pp. 101-110.Pollett, Frederick C. 1972. Nutrient contents of peat soils inNewfoundland. Proc. 4th Internat. Peat Congr. I-IV. Helsinki.pp. 461-468.Retnakaran, A. 1972. The male reproductive system of thespruce budworm, Choristoneura fumiferana. 3. Incorporationinto seminal components of leucine released duringapolysis. Experimentia. 28:1411-1412.Rogers, I. H., and J. F. Manville. 1972. Juvenile hormonemimics in conifers. I. Isolation of (-)-cis-4-[l' (R)-5'-Di-21

methyl-3'-oxohexyll-cyclohexane-l-carboxylic acid fromDouglas-fir wood. Can. J. Chem. 50:2380-2382.Salonius, P. 0. 1972. Effect of DDT and fenitrothion on forestsoilmicroflora. J. Econ. Entomol. 65(4):1089-1090.Sayn-Wittgenstein, L. 1971. Large scale aerial photographyand radar altimetry: the state of art. In Application ofRemote Sensors in Forestry. Internat. Union For. Res.Organ. Section 25. pp. 99-108.Scarratt, J. B. 1972. Container size affects dimensions of whitespruce, jack pine planting stock. Tree Planters' Notes23(4):21-25.Shields, J. K., R. L. Desai and M. R. Clarke. 1972. Zinc treatmentto prevent brown stain in pine lumber. For. Chron.48 (December).Smith, R. B. 1973. Factors affecting dispersal of dwarf mistletoeseeds from an overstory western hemlock tree. NorthwestSci. 47(1):9-19.Turner, J. A. 1972. The drought code component of theCanadian forest fire behavior system. Dep. Environ., Can.For. Serv. Pub. 1316. 14 p.22

ecent publicationsMAY - JUNEBarton, G. M. 1973. Chemical color tests for Canadian woods. Can. For. Ind. (February).Cameron, J. W. MacBain. 1972. Implementation of biological control programs against forestpests. Proc. North Central Br., E.S.A. 27:43-47.Carlson, L. W. 1972. Fungicidal control of poplar leaf spots in Alberta and Saskatchewan.Can. Plant. Dis. Surv. 52(3):99-101.Chow, S. 1972. Thermal analysis of liquid phenol-formaldehyde resin curing. Holzforschung26(6) :229-232.Crampton, C. B. 1972. The distribution and possible genesis of some organic terrain patternsin the southern Mackenzie River Valley. Can. J. Earth Sci. 10:432.Dionne, Jean-Claude. 1972. Caractéristique des blocs erratiques des rives de l'estuaire duSaint-Laurent. Rev. Géogr. Montr. XXVI(2):125-152.Dionne, Jean-Claude. 1972. La denomination des mers du postglaciaire au Quebec. CahiersGéogr. Qué. 16:483-487.Dionne, Jean-Claude. 1972. Formes de corrosion dans l'anorthosite sur le rivage est du lacSaint-Jean. Cahiers Géogr. Qué. 16:489-493.Dionne, Jean-Claude. 1972. Micro-craters in muddy tidal flats of cold regions. Cahiers Géogr.Qué. 16:495-498.Dionne, Jean-Claude. 1972. Troncs d'arbres fossiles le long de la Sainte-Marguerite-Ouest(Saguenay). Rev. Géogr. Montr. XXVI(2):206-208.Dobie, J., and R. W. Neilson. 1973. These equations tell when to cut larger veneer cores formore lumber. Can. For. Ind. (February).Durzan, D. J. 1973. Nitrogen metabolism of Picea glauca. V. Metabolism of uniformly labeled14 C-L-proline and "C-L-glutamine by dormant buds in late fall. Can. J. Bot. 51:359-369.Durzan, D. J. 1973. The incorporation of tritiated water into amino acids in the presence ofurea by white spruce seedlings in light and darkness. Can. J. Bot. 51:351-358.Feihl, 0. 1972. Heating frozen and nonfrozen veneer logs. For. Prod. J. 22(10) :41-50.Fogal, W. H., and M.-J. Kwain. 1972. The effects of temperature on the occurrence of melanoticinclusions and related physiology in a sawfly, Gilpinia hercyniae. J. Insect Physiol.18:1545-1564.Frey, T., mid H. Van Groenewoud. 1972. A cluster analysis of the D matrix of white sprucestands in Saskatchewan based on the maximum-minimum principle. J. Ecol. 60:873-886.Gaudert, P., and M. N. Carroll. 1973. A plug test for plywood lumber composites. For. Prod.J. 23(1):31-36.Hatton, J. V., J. L. Keays and J. Hejjas. 1972. Effects of time, temperature and effective alkaliin kraft pulping of western hemlock. Pulp Pap. Mag. Can. 73(4):Tl03-T109.Hiratsuka, Yasuyuki. 1973. Sorus development, spore morphology, and nuclear condition ofGymnosporangium gaeumannii ssp. albertense. Mycologia. LXV(l) :137-144.Honer, T. G. 1972. A height-density concept and measure. Can. J. For. Res. 2:441-442.MacDonald, Bruce F., and G. M. Barton. 1973. Lignans of western red cedar (Thuja plicataDonn). XI. /3-Apoplicatitoxin. Can. J. Chem. 51(4):482-485.Marten, Gerald G. 1972. Censusing mouse populations by means of tracking. Ecology 53(5)859:867.Marshall, V. G. 1971. Effects of soil arthropods and earthworms on the growth of blackspruce. In IV. Colloquium Pedobiologiae Dijon, 14/19-IX-1970. Proc. 4th Colloq. Zool.Comm. Internat. Soc. Soil Sci. Institut National De la Recherche Agronomique. Paris.pp. 109-117.McIntosh, J. A. 1973. The dika tree feller. B. C. Lumberman. (March).McIntosh, J. A. and T. Szabo. 1972. Watch for these signs of white spruce heart shake.Can. For. Ind. (October).(Continued on page 21)

i-monthlyresearchnotesBrachiate tracheids in deformed wood of Abies.Parasites and predators of Hylobius warreni.Relationship between felling date and larval density ofMonochamus scutellatus.Lodgepole pine dwarf mistletoe on Douglas-fir in Alberta.Liquid cultures in polythene bags.Height, growth and survival of northern white spruce provenancesat Chalk River.Effect of age of white spruce seedlings on dormancy-inductingtreatments.Predicting potential volume growth by progeny testing white spruceplus trees.Vol. 29, No. 4, JULY-AUGUST, 1973.140Environment EnvironnementCanada CanadaForestry ServiceService des forets

i-monthlyresearch notes"A selection of notes on current research conducted bythe Canadian Forestry Service and published under theauthority of the Minister of the Department of theEnvironment. A French edition is published underthe title of Revue Bimestrielle de Recherches".BOTANYBrachiate Tracheids in Deformed Wood of Abies.—Zalasky (Can. For. Serv. Inf. Rep. NOR-X-48) has reportedon sclereid-like cells in traumatic tissue of Pinus and Populus.This paper reports the occurrence of brachiate tracheids inocclusion tissue from alpine fir [Abies lasiocarapa (Hook)Nutt.).Specimens were commonly collected from alpine fir inthe foothills region of the Bow, Clearwater, and Gregg rivers,Alberta at altitudes between 5000 and 6000 feet (1524 and1828 m). Curly grained wood was excised from the face ofthe frost canker and burl after removal of the bark. The woodwas precooked and pulped in a l:1 mixture of acetic acid and15% hydrogen peroxide and maintained in a vacuum ovenat 60°C up to 3 days. Resins were cleared by progressivelyrinsing and treating the pulp with 70% and 90% ethyl alcohol,Figure 1. Phase microscopy with a green filter. Note variationsin thickness of the cell wall of a brachiatetracheid. A. Bordered pits.a 1:l mixture of absolute alcohol and ethyl acetate andfinally pure ethyl acetate. The pulp was then rehydrated. Thecells were stained in chlorazol black, rinsed and stored inAman's lactophenol. Slides were prepared by putting a fewdrops of cell suspension on a slide and lowering a coverslipgently over it. Observations were made at low and highmagnifications; Figure 1 was taken at 250 magnifications.Brachiate tracheids are often dichotomously branchedand small, the largest measuring 125u x 150u. The mainbody of the tracheid measures 20u in diameter. Dichotomousbranching leads to diverse forms such as coronate, star-shaped,tuning-fork and Y-shapes. Platelets of incompletely maceratedtissues often consist of wedge-like formations, especially whendeformed tracheids are characterized by T-forms, sigmoidsand triangular-coronate forms having one end broad and theother end attenuated. The L-forms and T-forms are •usuallydilated at the junction of branches that taper, sometimessharply. Tracheids are often intermittently tapered and dilated.Branched cells and C-forms invariably enclose shorter globoseand ventricose tracheids aligned in the opposite direction.Some of them appear reticulate, perhaps due to fusion ofpapillate structures between branches and adjacent cells; othersresemble twin tuning-forks back to back. All forms characterizethe interlocking grain of sapwood contiguous with andthe occluding canker. The contorted cell structure suggestsfailure of the mechanism controlling shape during development,or damage to the active protein synthesizing system afterfreezing such as that described by Brown and Bixby (PlantPhysiology 49, Supplement p. 15, 1972). The latter is particularlyinteresting because cells have altered their formin the early as well as the late stages of development.—H. Zalasky, Northern Forest Research Centre, Edmonton,Alta.ENTOMOLOGYRelationship Between Felling Date and Larval Density ofMonochamus scutellatus.—Members of the genus Monochamus(Coleoptera: Cerambycidae) are economically importantinsects of forest products. Adult beetles lay their eggs intofreshly cut logs and their larvae tunnel into the wood, thusdegrading the lumber sawn from infested logs. I had observedthat some logs in logged areas and the logs of some burntareas were heavily attacked by Monochamus scutellatus Say,while other logs in the same logged areas and logs of otherburnt areas were almost free from attack, even though Monochamusadults were abundant in the immediate area. It washypothesized that felling date, or date of burn, might be animportant factor in determining the density (number per unitarea of log surface) of Monochamus larvae. Felling dateinfluenced the density of the bark beetles Trypodendronlineatum (Dyer and Chapman, Can. Entomol. 97:42-57, 1965;Christiansen and Saether, Norwegan J. Entomol. 15:28-30,1968), and Dendroctonus rufipennis (Kby.). (D. Engelmanni;McComb, USDA, Forest Serv., Intermountain Forest & RangeExp. Sta., Res. Note 23, 1955), and to a lesser degreeIps pini (Say) (Sartwell, USDA, Forest Serv., Pacific N.West Forest & Range Exp. Sta., Res. Note 131). Three papershave related felling date to ecological data of wood borers.Tothill (New Brunswick Land Dep., Annu. Rep. 63:86-87,1924) observed that logs cut from trees burned in May, Juneand July were more heavily attacked by Monochamus thanlogs from trees burned in the fall; (Morley Can. Entomol.71:243-248, 1939) related Monochamus larval development tofelling date; and Vanderwal and Ross (Can. Dep. Forestry,Bi-mon. Res. Notes 24:31, 1968) reported that the densityof Tetropium velutinum LeC. was greater in logs cut in Mayand June than in logs cut at other times of the year. ThisO23

paper reports the results of studies to determine the relationshipbetween felling date and density of Monochamus larvalentrance holes in pine and spruce logs.The studies were done near Blairmore, Whitecourt andWandering River Alta., where in April, June, August, Octoberand December of 1967 10 pine and 10 spruce were felled ineach month in each locality. In all three localities Picea glauca(Moench) Voss was felled, Pinus contorta Dougl. was felledat Blairmore and Whitecourt, and Pinus banksiana Lamb.at Wandering River. The felled trees were co-dominant andsimilar in size (avg dbh, 9.1 in.; 23.1 cm), and appearedhealthy when cut. The trees were limbed, but not bucked,except when necessary to enable the logs to rest on or nearthe ground. All plot areas were fully stocked so all felledtrees were in partial shade. Estimates of the density ofMonochamus larvae were obtained at the end of the 1969season, with the sequential samplying system of Safranyik andRaske (J. Econ. Entomol. 63:1903-1906, 1970) which wasslightly modified to yield number of Monochamus larvae persquare foot (30.48 cm') of surface for each log. AdultMonochamus population levels and fecundity were assumedto be about equal for both the 1967 and 1968 ovipositionperiods, Estimates of density were averaged for each groupof 10 trees and summarized by location, felling date, and hostspecies. No apparent difference in larval density existed betweenpine and spruce, therefore, the data for these hosts werecombined.The densities of Monochamus larvae, expressed in numberof larval entry holes per square foot of log surface, wererelated to felling date of the tree (Fig. 1). Generally, logscut in spring and early summer had higher densities than logscut in fall and winter. June-cut logs averaged about two larvalentrance holes per square foot, while December-cut logsaveraged about one-half larval entrance hole per square foot.The density in logs at Blairmore was greater at each correspondingfelling date than that in logs at the other locations.This difference was most pronounced in trees felled in Augustand October. These results suggest that either more eggs werelaid into logs at Blairmore or that larval survival was greater.In all three areas, mortality of early instar larvae was judgednegligible due to the absence of incomplete larval mines.Logging companies may reduce degrade losses caused byMonochamus by concentrating felling operations in the falland winter, and by prompt processing of spring-cut logs.DeeJune Aug OctFelling DateLEGENDBlairmoreWanderingWhitecourtFigure 1. Average density in Monochamus larval entry holes(numbers = Sx).RiverHowever, if logs must be left in the forest for a summer season,it is recommended that logs cut in fall and early winter beleft, as they are likely to contain fewer Monochamus larvae thefollowing fall than logs cut in early spring.—A. G. Raske,Northern Forest Research Centre, Edmonton, Alta. (Presentaddress Newfoundland Forest Research Centre, St. John's,Nfld.)Some Parasites and Predators of Hylobius warreni inAlberta.—During population studies on the weevil, Hylobiuswarreni Wood, in semi-mature forests of lodgepole pine [Pinuscontorta Dougl. var. latifolia Engelm.], several organisms werefound in association with the weevil that caused mortality orare suspected of contributing to mortality or to reduce fecundity.All of the collections, except where otherwise stated,were made about 30 miles southwest of Edson, Alta. (53° 13'N116° 44'W).The most common parasite of H. warreni was the waspDolichomitus tuberculatus tuberculatus (Fours.). Specimenswere obtained at Embarras (near Lake Athabasca) and nearRobb, Edson and Ricinus. Townes and Townes (U.S. Nat.Mus. Bul. No. 216, Pt. 2:124-127, 1960) noted that this subspeciesis holarctic. Males were less numerous and slightlysmaller than females. The life cycle in Alberta is as follows:most adults emerge between mid-June and mid-July, and mostovoposition is during July when single eggs are placed in theresinous pupal chamber made by the mature weevil larva.The newly hatched parasite larva feeds externally on theresting last-instar weevil larva and matures in about 2 weeksafter consuming the body contents of the weevil. It then preparesa greyish-brown pupal case within the weevil pupalchamber where it remains until the following spring. Developmentto the adult begins after mid-May. Additional hosts ofthis parasite include Hylobius pinicola (Couper) and Monochamusscutellatus (Say) (Townes and Townes, loc. cit.),This parasite accounted for up to 5% mortality of last-instarweevil larvae.Of 36 adult female H. warreni dissected, one contained 10specimens of a nematode in its abdominal cavity; these wereclassified in the superfamily Tylenchoidea. The infected weevilwas collected on 31 August and had smaller ovaries thanother females collected during the same period. The presenceof sperm in the spermatheca and food throughout the digestivetract, indicated that the weevil had mated and had beenfeeding. All nematodes were about 3 mm long and lay in adorsal position external to the digestive tract. According toDr. Kloss (personal communication), the nematode is hermaphroditicin the weevil and the succeeding stage would begonochoristic and live in the soil. Their effect on the weevilwould likely reduce fecundity or shorten the life of the femalesince most of the parasites occupied the region of ovaryexpansion.Mites attached externally on the ventral abdomen of adultweevils were common and appeared more abundant after June.Of 74 mites collected, 72 were on females and two on males.A sample of 12 mites was identified as Hericia sp. (nearH. fermentationis Vitz.); family Saproglyphidae, subfamilyCarpoglyphinae. Dr. Lindquist (personal communication)indicated that the mites were an immature form and that theadult form may live upon the sap oozing from trees. Theeffect of the mite upon the weevil is unknown but its attachmentmay serve at least for dispersion.The entomogenous fungus, Beauveria bassiana (Bals.)Vuill., was identified on several dead adult weevils. Manydead last-instar larvae, pupae and teneral adults in pupal cellswere found covered with a white mycelium believed to beB. bassiana. This pathogen might prove useful in an integratedmethod of control for H. warreni similar to the method24

described for control of H. abietis, in which a weak insecticide(DTHP) with a suspension of B. bassiana spores is used (Samsináková and Novak, Anz. Schadlingsk 40:20-27, 1967). Thisfungus is a natural mortality factor of Hylobius rhizophagusMillers (Goyer and Benjamin, J. Econ. Entomol. 64:562, 1971),and mortality of Hylobius pales (Herbst) adults was shownto be related directly to the concentration of • B. bassianaspores (Walstad and Anderson, J. Econ. Entomol. 64:322-323,1971).Two fly larvae found attached to, and which later killed,a mature larva and a pupa of H. warreni were identified asbelonging to the family Asilidae, subfamily Laphriinae. Littleis known about the larval habits of Laphriinae, except thatthey inhabit soil, wood and leaf mould and are either predaciousor scavenging (Imms, A general textbook of entomology,Methuen, London, 9th ed.: 628-629, 1957). Eltonet al. (Z. angew. Ent. 55:1-54, 1964) provided evidence that,in Holland, certain Laphria species are at least partly predaciouson larvae of Hylobius abietis L. in pine stumps. Theeffect of this predatory fly on H. warreni populations is believedto be insignificant.The shrew, Sorex cinereus cinereus Kerr., was commonlytrapped in the weevil study area but examination of stomachcontents of 46 individuals failed to reveal sclerital remains ofthe weevil. This may have been because the weevils wererelatively scarce and the shrews may have been conditionedto search for more abundant species such as carabids. Sclericalfragments of carabids were easily recognized. Another possibilityis that complete digestion of adult weevils may haveoccurred as about 8 hours elapsed between the time of emptyingthe traps and the time of peak adult weevil locomotionon the forest floor, between 2200 and 0100 hours.I express my thanks to the specialists for the. taxonomicidentification of the parasites and predators of H. warreni:Mr. G. S. Walley (ichneumonid), Dr. J. R. Vockeroth (asilid)and Dr. E. E. Lindquist (mite), all at the Entomology ResearchInstitute, Ottawa, Canada. Dr. Gertrude R. Kloss, Departmentof Zoology, Secretary of Agriculture, Sao Paulo, Brazil andDr. W. Rühm, Institute of Parasitology, Hanover, Germany,identified the nemotodes.—H. F. Cerezke, Northern ForestResearch Centre, Edmonton, Alta.PATHOLOGYLiquid Cultures in Polythene Bags.—An inexpensivemethod of producing large quantities of mycelium of theinsect pathogen, Cordyceps militaris (Fr.) Link, is being usedat the P.F.R.C. in Victoria. The method was developed primarilyto obviate buying large numbers of glass Erlenmyerflasks. It employs sterilized polythene bags and possessesseveral advantages in storage and processing of the endproduct.Polythene bags (10 lb size, 8 x 18 inches — 20 x 46 cmapprox.) are shaken with 70% ethanol and rinsed with sterilewater. They are then placed upright in a large basin withvertical sides for support. Sterilized medium (500 ml/bag)and inoculum are added and the tops are closed with a large,sterile, foam-plastic plug, held in place by an elastic band.These operations are performed in a laminar flow sterile airbench.Inoculated bags are placed on a shelf where there is asupport for the top (Fig. 1), and the bottom is flattened togive maximum culture area inside the bag.As only the fungus mat was required, it was possible todraw off the liquid at the end of the culture period by puncturinga small hole in the bottom of the bag. The air wasthen expelled, the plug removed and the collapsed bag wrappedFigure 1. Polythene bag cultures of Cordyceps militaris onmalt extract broth.around the mat. In the case of C. militaris, the packagedmats were frozen and stored in this form until needed in fieldtrials, when the ease of transporting the frozen mats becomesan important factor.The method, best suited to organisms that do not requireagitation during growth, is equally suitable for obtainingeither the mat or the growth medium. In the latter case,the unwanted mycelium could be disposed of without removingit from the bag and thus contamination of the air oroperator would be avoided. The savings in glassware andstorage space are considerable when a large amount of fungusmaterial is produced at one time. Where it is desirable tomanipulate a culture during incubation, e.g. wood blocks ina liquid medium, the plastic bag method would be applicable.No changes in morphology or viability of C. militaris havebeen noted after culturing in polythene.Polythene, though inexpensive, has had only limited usein microbiology (Norris and Ribbons, "Methods in Microbiology"Vol. 1, p. 51. Academic Press, New York. 1969).This new method exploits the advantages of this material andsuggests a wider application in the field of liquid culturing.A. Funk, Pacific Forest Research Centre, Victoria, B.C.Lodgepole Pine Dwarf Mistletoe on Douglas-fir in Alberta.—Lodgepole pine dwarf mistletoe [Arceuthobium americanumNutt. ex Engelm.] was discovered on Douglas-fir [Pseudotsugamenziesii (Mirb.) Franco] in 1972 approximately 50 miles(80 km) west of Calgary, Alta. Three typical swellings(Fig. 1) and infection structures of dwarf mistletoe (Fig. 2)were found on one tree, 6 ft (1.8 m) high, which was surroundedby young lodgepole- pine [Pinus contorta Dougl. var.latifolia Engelm.] infested with dwarf mistletoe. Previously,A. americanum was recorded once on Douglas-fir at Kamas,Utah (Hawksworth and Wiens, U.S. Agric. Handbook 401,234 p. 1972). Douglas-fir dwarf mistletoe [A. douglasiiEngelm.] causes large witches' brooms and occurs in limitedareas of southeastern British Columbia (Kuijt, Can. Nat. Mus.Bull. 186:134-148, 1963; Smith, Ecology 53:729-734, 1972)approximately 160 miles (260 km) west of the present location.During a study of dwarf mistletoe development from seedon lodgepole pine, I noted that numerous seeds were depositedon the Douglas-fir. In May 1966 and 1967 approximately 200seeds were recorded and re-examined in September and May1966-68. Most seeds germinated and grew holdfasts as theydid on lodgepole pine. In 1972 one swelling was locatedwhere a seed dispersed in 1966 was recorded.25

SILVICULTUREHeight, Growth and Survival of Northern White Spruce Provenancesat Chalk River, Ontario.-Northern provenances ofmost forest tree species, when planted in the south, generallygrow slowly, and are susceptible to spring frost because theyflush early. In an experimental plantation established in 1963at Chalk River (46° N, 77.4° W, 120 frost free days) somenorthern white spruce [Picea glauca (Moench) Voss] provenancesgrew as rapidly as the local provenance and survivedwell. Such exceptional northern provenances may be usefulin southern sites with frequent early autumn frosts to whichnorthern provenances tend to be resistant.The experimental plantation included 13 northern provenancesand the local Chalk River provenance as a control(Table 1). Trees were planted 5 x 5 feet (1.5 m x 1.5 m)apart in 25 tree plots with six replications. At planting, in1963, seedlings from Quebec and Ontario (except Moosonee)were 4 years old and the others were 5 years old, but theolder seedlings were not larger. The planting site was dry,and sloped slightly to the west.Figure 1. Branch swelling caused by dwarf mistletoe (A.americanum) on Douglas-fir.Figure 2. Dwarf mistletoe infection structures (radicle andholdfast) at base of needle at center of the swelling.Swellings measured 0.4-0.8 cm wide by 3.0-4.5 cm longand had smooth bark but no buds, aerial shoots or basal cupsof dwarf mistletoe. We are continuing our observations ofthese swellings.Further work is needed to determine the significance oflodgepole pine dwarf mistletoe on Douglas-fir. In easternAlberta, Douglas-fir often is present among infested lodgepolepine and presumably is occasionally infested. Damage toDouglas-fir is probably slight and inconspicuous. Most importantly,the dwarf mistletoe on Douglas-fir would survive sanitationtreatments applied to infested pine stands and possiblycould infest or reinfest healthy pines. Although my observationsand those of Hawksworth and Wiens (1972), that thisdwarf mistletoe on Douglas-fir did not grow shoots and berries,do not imply that dwarf mistletoe cannot spread from Douglasfir,as fruiting on Douglas-fir could be stimulated by sanitationtreatments.-J. A. Muir, Northern Forest Research Centre,Edmonton, Alta.TABLE 1Height growth and survival of northern white spruce provenances6 years from planting.ProvenanceW NPlace cm inches %Long LatHeight Survival2482 82.5 49.3 Kapuskasing, Ont. 76 30 672692 81.6 52.2 Moosonee, Ont. 74 29 612464 77.4 45.9 Chalk River, Ont. 73(80)* 29(31) 51(49)*2604 71.1 48.7 Shipshaw River, P.Q. 73 29 372454 75.6 47.0 North Baskatong Lake, 71 28 61P.Q.2488 101.6 54.6 Channing, Man. 71 28 482472 67.8 48,2 Price, P.Q. 70 28 672494 53.8 60.1 Melville Bay, Nfld. 69 27 452503 123.0 54.0 Summit Lake, B.C. 62 24 352490 106.0 59.3 Stony Rapids, Sask. 61 24 462493 56.4 52.6 Port Hope Simpson, 60 24 52Nfld.2483 86.1 49,7 Pagwachuan Lake, Ont, 60 24 722556 92.9 56.9 York Factory, Man. 47 19 6$2496 135.6 60.8 Mile 930, Alaska Hwy, 39 15 44YukonMean 65 26 54Heights in parenthesis refer to trees.* In surround rows.Provenances varied significantly in survival and height(p

TABLE 1Heights and diameters at breast height of Chalk River, Ont.plus trees at 11 and 22 years of age, and expected geneticgains from selecting the tallest 10%.Age11 years22 yearsProgeny No. Height (cm) Height (cm) DM (cm)42 201 692 13.841 176 551 11.951 175 639 11.148 155 544 10.056 148 573 10.124 144 576 9.720 137 405 8.268 131 583 9.543 125 584 9.932 122 537 9.553 115 595 9.544 111 502 8.5Mean 145 566 10.2408 2,635 1.6014Uo 1301 11,254 3.6989119 0.76 .7007 .8123Genetic gain-cm 38.4 93.5 2.52% 26 17 25after 11 growing seasons (ft x d 5 of the selections, i.e. experimentalmean + genetic gain, compared with h x d 2 of theexperimental mean).Although these results are based on a small experiment,they support a hypothesis that early results of white spruceprogeny tests are reliable in evaluating superior productivity(King, Nienstaedt and Macon, USDA For. Serv., Res. NoteLS-66, 1965) and that percent increase in volume growth substantiallyexceeds estimated percent increases in height growth.-A. H. Teich, Petawawa Forest Experiment Station, ChalkRiver, Ont., and M. A. K. Khalil, Newfoundland Forest ResearchCenter, St. John's, Nfld.(Continued from back coyer)Follett, Frederick C. 1972. Nutrient contents of peat soils inNewfoundland. Proc. 4th Internat. Peat Congr. I-IV. Helsinki.pp. 461-468.Retnakaran, A. 1972. The male reproductive system of thespruce budworm, Choristoneura fumiferana. 3. Incorporationinto seminal components of leucine released duringapolysis. Experimentia. 28:1411-1412.Rogers, L H., and J. F. Manville. 1972. Juvenile hormonemimics in conifers. I. Isolation of (-)-cis-411' (R)-5'-Dimethyl-3'-oxohexyll-cyclohexane-l-carboxylicacid fromDouglas-fir wood. Can. J. Chem. 50:2380-2382.Salonius, P. 0. 1972. Effect of DDT and fenitrothion on forestsoilmicroilora. J. Econ. Entomol. 65(4):1089-1090.Sayn-Wittgenstein, L. 1971. Large scale aerial photographyand radar altimetry: the state of art. In Application ofRemote Sensors in Forestry. Internat. Union For. Res.Organ. Section 25. pp. 99-108.Scarratt, J. B. 1972. Container size affects dimensions of whitespruce, jack pine planting stock. Tree Planters' Notes23(4):21-25.Shields, J. K., R. L. Desai and M. R. Clarke. 1972. Zinc treatmentto prevent brown stain in pine lumber. For. Chron.48 (December).Smith, R. B. 1973. Factors affecting dispersal of dwarf mistletoeseeds from an overstory western hemlock tree. Northwest Sci. 47(1):9-19.Turner, J. A. 1972. The drought code component of theCanadian forest fire behavior system. Dep. Environ., Can.For. Serv. Pub. 1316. 14 p.Martineau, R., and Paul Benoit. 1973. A sampling techniquefor estimating numerical trends in larval populations ofinsect defoliators on conifers, II. Modification and operationaluse of the technique for extensive sampling of sprucebudworm populations in Quebec. Phytoprotection, 54:23-31.Mitchell, D. L., D. Hocking and W. C. Kay. 1972. Extrudedpeat cylinders: their physical characteristics as affectingtree seedling growth and greenhouse drought tolerance.Can. J. Forest Res. 2:479-486.Muir, J. A. 1972. Increase of dwarf mistletoe infections onlodgepole pine. Can. J. Forest Res. 2:413-416.Nienstaedt, Hans and Abraham Teich. 1972. Genetics ofwhite spruce. U.S.D.A. For. Serv. Res. Pap. WO-15. 24 p.Oswald, E. T., and L. W. Minty. 1971, Soil acarine fauna ofsoutheastern Manitoba. II. Riparian communities. Man.Entomol. 5:71-78.Percy, J. 1973, The intranuclear occurrence and fine structuraldetails of schizonts of Perezia fumigeranae(Microsporida:Nosematidae) in cells of Choristoneura fumiferana(Clem.) (Lepidoptera: Tortricidae). Can. J. Zool.51:553-554.Pnevmaticos, S. M., T. A. Jaeger and E. Perem. 1972. Factorsinfluencing the weight of black spruce and balsam firstems. Can. J. Forest Res. 2:427-433.Quednau, F. W. 1972. A new species of Hoplochaitophorusfrom swamp white oak, with a key to the apterous formsof the genus (Homoptera: Aphididae). Can. Entomol.104:1539-1541.Quednau, F. W. 1973. Taxonomic notes on aphids from Nepaland India with descriptions of a new genus and two newspecies (Homoptera: Aphididae). Can. Entomol. 105:217-230.Reeks, W. A. 1971. Impact of insect outbreaks in Manitoba.Man. Entomol. 5:5-16.Retnakaran, Arthur. 1973. Hormonal induction of supernumeraryinstars in the spruce budworm, Choristoneurafumiferana (Lepidoptera: Tortricidae). Can. Entomol.105:459-461.Rose, A. H. 1973. Noteworthy forest insects in Ontario in1971. Proc. Entomol. Soc. Ont. 102:10-12.Sanders, C. J. 1973. Aggregation of alate carpenter ants inOntario. Proc. Entomol. Soc. Ont. 102:13-16.Salamon, M. 1973. Comparison of kiln schedules for dryingspruce. For Prod. J. 23:45-49.Shaw, G. G., and C. H. A. Little. 1972. Effect of high ureafertilization of balsam fir trees on spruce budworm development.pp. 589-597. In Insect and Mite nutrition. North-Holland. Amsterdam. 1972,Shen, K. C. 1973. Steam-press process for curing phenolicbondedparticleboard. For. Prod. J. 23:21-29.Shrimpton, D. M. 1973. Extractives associated with woundresponse of lodgepole pine attacked by the mountain pinebeetle and associated microorganisms. Can. J. Rot. 51:527-534.Smith, R. S. 1973. Continuous automatic measurement ofrhythms in fungal respiration using a gas chromatograph.Can. J. Bot. 51:701-710.Shell, W. M., and A. B. Berry. 1973. Development of unthinnedwhite spruce plantations to age 50 at PetawawaForest Experiment Station, Can. For. Serv. Pub, 1317.18 pp.Shell, W. M., and A. B. Berry. 1973. Yield of unthinned redpine plantations at the Petawawa Forest ExperimentStation. Can. For. Serv. Pub. 1320. 16 pp.Stillwell, M. A., R. E. Wall, and G. M. Strunz. 1973. Production,isolation, and antifungal activity of scytalidin, ametabolite of Scytalidium species. Can. J. Microbiol. 19:597-602.28

ecent publicationsJULY -- AUGUSTBenoit, P. and R. Martineau. 1972. Principaux insectes forestiers au Québec en 1972. Ann.Soc. Ent. Québec 18(1) :10-14.Bohaychuk, W. P., and R. D. Whitney. 1973. Environmental factors influencing basidiosporedischarge in Polyporus tomentosus. Can. J. Bot. 51:801-815.Bowland, James G. 1972. The use of wood and wood-based building materials in new residentialconstruction in Canada, 1969. Can. For. Serv. Pub. 1312. 99 pp.Brix, H. 1972. Nitrogen fertilization and water effects on photosynthesis and earlywoodlatewoodproduction in Douglas-fir. Can. J. Forest Res. 2:467-478.Chow, S. 1973. Molecular rheology of coniferous wood tissues. Trans. Soc. Rheol. 17(l):109-128.Chow, S. 1973. Thermal analysis of liquid phenol-formaldehyde resin curing. Holzforschung26(6):229-232.Cserjesi, A. J. 1972. Detoxification of chlorinated phenols. Int. Biodetn. Bull. 8(4):135-138.Dionne, Jean-Claude. 1972. Ribbed grooves and tracks in mud tidal flats of cold regions.J. Sediment. Petrol. 42:848-851.Dionne, Jean-Claude. 1973. Structures cylindriques verticales dans du quaternaire a Arthabaska,Québec. Sediment. Geol. 9:53-63.Dobie, James. 1973. Economies of scale and trends in sawmill capacity in British Columbia.For. Chron. 49 (April).Eis, S., and J. Inkster. 1972. White spruce cone production and prediction of cone crops.Can. J. Forest Res. 2:460-466.Ennis, T. J. 1972. Low chromosome number and post-reductional X0 in Gelus californicus(Lec. ) (Coleoptera: Curculionidae). Can. J. Genet. Cytol. XIV: 851-857.Etter, H. M. 1972. Effect of nitrogen nutrition upon sugar content and dry weight of juvenilelodgepole pine and white spruce. Can. J. Forest Res. 2:434-440.Finnegan, R. J. 1973. Diurnal foraging activity of Formica sublucida, F. sanguinea subnuda,and F. fossaceps (Hymenoptera: Formicidae) in Quebec. Can. Entomol. 105:441-444.Foster, N. W., and S. P. Gessel. 1972. The natural addition of nitrogen, potassium andcalcium to a Pinus banksiana Lamb. forest floor. Can. J. Forest Res. 2:448-455.Griffiths, K. J. 1973. Discrimination between parasitized and unparasitized hosts byPleolophus basizonus (Hymenoptera: Ichneumonidae). Proc. Entomol. Soc. Ont. 102:83-91.Hatton, J. V., and J. Hejjas. 1972. Effects of time, temperature and effective alkali in kraftpulping of trembling aspen (Populus tremuloides Michx.). Pulp Pap. Mag. Can. 73:T218-T222.Lam, L. K. M., D. P. C. Fung, Y. Tsuchiya and K. Sumi. 1973. Identification of cis-4, 5-epoxy-2-pentenal from pyrolysis of H3P0-treated cellulose. J. Appl. Polym. 17:391-399.Lavallée, A. et P. Benoit. 1973. Insectes et maladies des arbres. Région de Québec - 1972,de la revue Forêt-Conservation 39(4). 22 pp.Lesko, G. L., and J. D. Lindsay. 1973. Forest/soil relationships and management considerationsin a portion of the Chip Lake map area, Alberta. Alta. Res. Counc. Rep. 73-166 pp.Lindquist, 0. H. 1973. The Adelgidae (Homoptera) on forest trees in Ontario with a key togalls on spruce. Proc. Entomol. Soc. Ont. 102:23-27.Lindquist, 0. H., and W. J. Miller, 1973. A key to sawfly larvae feeding on the foliage ofspruce and balsam fir in Ontario. Proc. Entomol. Soc. Ont. 102:118-122.Little, C. H. A., and K. Loach. 1973. Effect of changes in carbohydrate concentration on therate of net photosynthesis in mature leaves of Abies balsamea. Can. J. Bot. 51:751-758.Manley, S. A. M. 1972. The occurrence of hybrid swarms of red and black spruces in centralNew Brunswick. Can. J. Forest Res. 2:381-391.(Continued on page 28)

i-monthlyresearchnotesHot-water technique to remove insect eggs from. foliage.Smaller European elm bark beetle at Ottawa.Dispersal of second instar spruce budworm.Erratum.Burning properties of forest fuels.Forests affected by sulphur dioxide.Biometer flask for soil respiration.Vol. 29, No. S, September-October, 1973.Environment EnvironnementCanada CanadaForestry ServiceService des forêts

i-monthlyresearch notes"A selection of notes on current research conducted bythe Canadian Forestry Service and published under theauthority of the Minister of the Department of theEnvironment. A French edition Is published underthe title of Revue Bimestrielle de Recherches".ENTOMOLOGYA Hot-water Technique to Remove Insect Eggs FromFoliage.—An improved technique was devised to remove eggsof western blackheaded budworm [Aclevis gloverana Walsingham]from western hemlock [Tsuga heterophylla (Raf.) Sarg.]foliage to facilitate counting. It was developed from a poachingmethod used on the spruce budworm [Choristaneura fumiferana(Clemens)] (Eidt and Cameron, Bi-Mon. Res. Notes26: 46-47, 1970). Previously, blackheaded budworm eggs wereremoved from foliage by soaking in a 1.5% sodium hydroxidesolution, followed by a spry wash and filtration (Condrashoff,Can. Ent. 99:300-303, 1967). A similar method was developedto separate budworm hibernacula (Miller et al., Can. For.Serv. Info. Rep. M-X-25, 1971). Although egg recovery wassatisfactory, this method was slow, and foliage dry weightsthat formed the basis of our sample method were reduced.Samples are trimmed to 18 inches in length, and thefresh weight is recorded. Each branch is immersed in a 3000ml beaker of boiling water which removes all eggs within 30seconds; longer immersion removes needles, necessitatingscreening. The branch is swirled in the water with tongs toensure that all eggs are free to settle out. A large supply ofboiling water can be obtained by piping steam into a 45 gal(2051) drum containing 25-30 gal (114-1361) of water. Thewater and eggs are slowly poured into an 18.5 cm Buchner funnelwith attached vacuum; grade 202 coarse filter paper (ReeveAngel, 9 Bridewell Place, Clifton, New Jersey) is used to speedfiltering. A circular plexiglass ring, placed around the edge ofthe labelled filter paper, prevents eggs from floating underneath.The container and ring are rinsed and examined after eachfiltering to ensure that no eggs stick to the apparatus. Eggsor the filter paper can be counted immediately, or the papersmay be stored between polyethylene sheets in a refrigerator ordeep freeze for counting later.Bulky branches should be cut into small segments to ensureproper immersion; this increases the amount of debris inthe water and slows counting. To alleviate this problem, pourthe water and eggs onto two screens (mesh #20 and #50 U.S.Series Equiyalent). The top screen removes needles, branchletsand coarse debris, which must be repeatedly mixed undera spray rinse. The bottom screen, which contains the eggs,is inverted over a large plastic funnel and the contents washedinto a 1-qt (l.l ml) sealer and then into the Buchner funnel,as previously described. Adequate rinses must be used.Two people can process 70 branch samples per day withthe screens; whereas without them, up to 200 samples can behandled. This difference is compensated, to some extent, bythe ease of counting eggs from the screened process.Reliability of this procedure was tested by processingbranches by the sodium hydroxide method after all eggs hadpresumably been removed by the hot-water technique. Only11 eggs were recovered from 100 branches that had over 2000eggs. Thus, this procedure was simpler, faster, and appearedto be almost as reliable as the sodium hydroxide method.This method was also tested with eggs of the false hemlocklooper [Nepylia freemani Munroe] deposited on Douglas-firbranches. Screens could not be used effectively, as the eggsoften remained in clusters and were removed with the debrisby the first screen. When the maximum likelihood method(Shepherd and Gray, Can. Ent. 104: 751-754, 1972) withthree washes is used to estimate total population, 84% of 2970eggs were recovered in the first wash and a total of 98% inthree washes. Visual counts of eggs on foliage only yielded82% of the total and required considerably more time. Removalof eggs remained relatively constant with each wash (74-84%):therefore, the method was considered satisfactory for thisspecies, provided three washes and the maximum likelihoodmethod were used to estimate density. This may be a fastand accurate technique for extracting eggs of other species,but it should be checked for each species of insects before thetechnique is accepted.—T. G. Gray, R. F. Shepherd and C. S.Wood, Pacific Forest Research Centre, Victoria, B.C.Smaller European Elm Bark Beetle Found in Ottawa.—Reports by the Forest Insect and Disease Survey, Great LakesForest Research Centre, show that the smaller European elmbark beetle [Scolytus multistriatus (Marsh)], is distributed generallythroughout southwestern Ontario below 44°30'N, in theBruce Peninsula, roughly south of a line across Barrie at LakeSimcoe, Fenelon Falls, slightly north of Peterborough, Bellevilleand Kingston, and along a narrow belt following the St.Lawrence River approximately to Morrisburg in easternOntario.Thomas (Bi-mon. Res. Notes 27(1):3, 1971) observedthat the rate of dispersal of S. multistriatus northward hasdeclined in recent years and in some areas appears virtuallystatic. He suggests that low winter temperatures may be regulatingthe northward spread of the insect. Preliminary testsby Thomas indicate that the mean freezing point of S. multistriatuslarvae appears to be approximately —30°C (-22°F)(Thomas, ibid.).Scolytus multistriatus was found at one location on asingle, standing, diseased elm in Ottawa along the OttawaRiver at Remic Rapids on 22 June 1973. This is approximately55 miles (88.50 km) north of its nearest known distributionin Ontario. Numerous brood and larval galleriestypical of the smaller European elm bark beetle were foundon the dead portion of the elm at a height of 10-20 ft (32.8-65.6 m). The lower trunk of the elm was still alive at the timeof collection and no galleries were found in this region. Deadadults of S. multistriatus were found in a few of the galleries.Detailed examination of the collected elm materialrevealed that none of the larvae above snow level survivedthe low 1972-73 winter temperatures in this region as no springdevelopment was evident. Table 1 shows temperature datafrom three locations in Ottawa obtained from the Departmentof the Enyironment, Atmospheric Environment Service.TABLE 1Temperature Data, Ottawa (October 1972-March 1973)Weather No. of days equal to or below LowestStation —10°F —15°F —20°F temperature(-23.0°C) (-26.1°C) (-28.9°C) (°F) (°C)National ResearchCouncil 11 8 2 —24 —31.1(Montreal Road)Agriculture Canada(Central Experimental 12 5 2 —22 —30.0Farm)International 10 2 1 —20 —28.9AirportThese data provide supporting evidence that low wintertemperatures may be regulating the northward dispersal ofS. multistriatus. A survey for further S. multistriatus will bemaintained in this area in Ottawa.—E. S. Kondo and G. D.Huntley, Great Lakes Forest Research Centre, Sault Ste. Marie,Ont.29

Dispersal of Second Instar Spruce Budworm.—Dispersalof the spruce budworm [Choristoneura fumiferana (Clem.)]occurs three times during its life cycle: in the fall, by firstinstar larvae; in the spring, by second instar larvae; and inlate summer, by moths. These dispersals affect the distributionof the budworm and, in the case of first and second instarlarvae, result in high mortality (Miller, Can. J. Zool. 36:409-422, 1958), thus they play a major role in the populationdynamics of the insect.Only a few facts are known about the springtime dispersalof second instar larvae. Date of emergence from thehibernaculum is determined by the rate of accumulating degreedayheat units (Miller, Eidt, and McDougall, Bi-Mon. Res.Notes 27: 33-34, 1971). Emergents are photo-positive andcrawl toward the branch terminals, where turbulent windscause the dispersal by carrying away many larvae before theyestablish in protective or feeding sites (Wellington and Henson,Can. Entomol. 79: 168-170 & 195, 1947).The present investigation monitored the dispersal of secondinstar larvae from a surrounding, infested forest to agroup of nursery-grown trees used in budworm nutrition experiments.The objectives were to detail the beginning, intensity,and duration of dispersal in relation to weather and to assessearly and late dispersing laryae for differences in survival,duration of larval development, and pupal weight.Wooden frames, 3 x 2 x 2 feet (0.9 x 0.6 x 0.6 m) highand covered with sheer polyester fabric were constructed tocatch wind-borne second instars. To prevent the wind fromblowing the larvae off the trap surfaces, 2-in. (5 cm) baffleplates were placed on all edges.Ten traps were spaced evenly in a north-south line acrossthe west end of the boundary nursery at the Acadia ForestExperiment Station. The traps were raised 1 foot (30.5 cm)above the ground and oriented with their 2- x 2-foot (0.6 x0.6 m) ends facing east and west. The ends of the trap linewere about 50 feet (15.2 m) from the forest, while the middlewas 150 feet (167 m) east of the forest. All traps were 4 to 6feet (l.2 to l.8 m) west of three closely spaced rows of7-year-old balsam fir trees used in budworm nutrition experiments.Although average spring emergence begins when 75 degreedays have been accumulated aboye 42°F (Miller et al., loc.cit.), trap monitoring was begun on 8 May at 67 accumulateddegree days to avoid missing any earlier emergence and dispersal.Hourly checking of all 10 traps was continued dailyfrom 9 AM to 7 PM until dispersal stopped. On days of highinflux, traps were checked every 15 min. to assure that nolarvae escaped.Degree days were computed (Miller et al., loc. cit,) usingthe air temperature data from a standard weather station 6miles (9.7 km) from the experimental site. Daily rainfalland cloudiness were recorded at the site.All larvae were removed carefully from trap surfaces andplaced in groups of 10 on artificial diet (McCorran, Can.Entomol. 97: 58-62, 1965) in closed l-oz. plastic containers.These larvae were reared under a constant high humidity anda 16-hour photoperiod at 70°F, then weighed and sexed asfirst-day pupae. Density per container was reduced to fiveduring the late third instar and again to two by the fifth instar.Food was renewed at these times and at one other time.Only 1.7% of all captured larvae had dispersed before11 May when 75 degree-days had been accumulated (Table 1),which is in agreement with previous results (Miller et al., loc.cit.).Although larvae were caught over a 15-day period, 77.4%were trapped between 14 and 18 May, when daily accumulateddegree days were consistently high. About two-thirds of all120iU.trft 100.tt0• BO1• B Ore11-O400:1• 202D09 10 11 12 1 2 3 4 6 6 7AM P MHOURFigure l. Total number of second instar spruce budwormlarvae caught in 10 traps from 8 to 22 May inconsecutive l-hour periods during the day,larvae were trapped during the hottest part of the day (Fig. 1).No association of daily numbers of dispersing larvae couldbe made with wind parameters. Winds varied from 6 to 23mph (9.7 to 37.0 km/h) with higher gusts and came from alldirections. However, very little wind may be required for dispersalsince most larvae were trapped on 18 May, when windspeeds were only ca. 7 mph (11.2 km/h).Rainfall markedly inhibited dispersal, even in the presenceof favorable increases in degree-days, as indicated bythe few larvae trapped on 15 and 16 May (Table 1).TABLE 1Daily weather and number of trapped second instar spruce budwormlarvae during the 1972 dispersal periodDate(May) Weather',Number ofbudworm Heat units',8 7 679 C 4 7110 O 0 7111 C 7 7512 O 6 7913 C 49 8614 C 131 10115 M 10 11416 O 4 12717 C 113 14618 C 232 16819 M 32 17620 C 24 18721 M 11 21122 C 3 22423 C 0 242Daytime sky condition C clear, 0 - Overcast, M mixed.Showers occurred on 12 May. Heavier rainfall occurred on 15 and 16May.', Accumulated degree-days above 42°F.Only 29% of the larvae survived to the pupal stage (Table2), which is a relatively low figure for an indoor rearing(McMorran, loc. cit.). Nevertheless, several significant correlationsinvolving dispersal date are apparent in the rearing data:the later the dispersal date, the poorer the survival (Table 2),the later the pupation date (r=0.55), and the lower the pupalweight (r=0.46 and 0.40, for females and males respectively).Pupal weight also was correlated with pupation date (r=0.82and 0.70, for females and males respectively); this correlationwas better than that between pupal weight and dispersal date,probably because the duration of pupation was twice that ofdispersal.30

TABLE 2Survival to pupation of second instar spruce budworm larvae trappedin the field in consecutive 4-clay dispersal periods and reared on artificialdiet in the laboratoryDate (May)8-11 12-15 16-19 20-22 TotalNo. dispersing 18 196 381 38 633No. survivingas pupae 10 85 81 6 182% survival 55.6 43.4 21.3 15.8 28.8The data on initiation and intensity of larval entrapmentare consistent with the concept that emergence from the hibernaculumis related to accumulated heat units above a certainthreshold (Table l; Fig. l). Most dispersal may be over in1 or 2 days (Morris and Mott, Mem. Entomol. Soc. Can.31:180-189, 1963) or last more than 1 week (Table 1),depending on the rate of accumulating degree days and thefrequency of heavy rainfall. Precipitation apparently eitherwashes most of the larvae out of the air or, in combinationwith cloud cover, reverses their normal photopositive response.Early and late dispersing second instar larvae differedappreciably, the latter having lower survival, lower pupalweight, and a later pupation date. Greater parasitism of lateemergents by Apanteles fumiferanae Vier. and Glyptaferanae (Vier.) may explain these differences (Renault, Can.Forest. Serv., Inform. Rep. M-X-32, 1972). On the other hand,Lewis (Can. Entomol. 92:881-891, 1960) observed that nonparasitizedlarvae are preferentially dispersed, suggesting thatother causes, e.g. infectious diseases, may also play a role.There may even be inherent differences in vigor between earlyand late dispersing larvae which are related back to early lifehistory events such as egg-laying order.—G. G. Shaw andC. H. A. Little, Maritimes Forest Research Centre, Fredericton,N.B.ErratumThe formula in Vol. 29, page 11, col. 1 should read:Infestation Index = sum of individual tree infestation ratingsX 100sum of maximum tree infestation ratings(4 x 3 x no. trees)FIREBurning Properties of Some Canadian Forest Fuels.—Work in the United States and in Australia has shown thatthe burning rates of forest fuels are depedent, amongst otherthings, upon inorganic content. (Pompe and Vines, AustralianForestry 30:231, 1966; King and Vines, Report, CSIRODivision of Applied Chemistry (Australia, July 1969)). A fewsimple experiments have, therefore, been carried out usingsome typical Canadian fuels to see if their behavior is similar.Burning rates of leaves and pine needles gathered fromrepresentative tree species in the eastern Provinces, were determinedin a laboratory on a recording balance. Definite differencesin burning properties were obseryed, and it appearedthat these differences were related to the inorganic contents ofthe fuels.The samples were enclosed in an open wire basket whichconveniently held 20 g of leaves, or needles, at a time. Theywere burnt on the pan of a continuously recording balance,so that changes in weight on combustion were easily followed.Care was taken to see that the volume occupied by thesamples was the same in all cases. This meant that the packingand aeration of the fuels (i.e., their volume to weight ratio)were as similar as possible. However, because of the highdensity of individual pine needles, it was easy to pack 20 gof needles into the basket, whereas it was more difficult tocompress an identical mass of leaves into the same space. Forthis reason, leaves were usually more "closely packed".Fuels were dried overnight in an oven 100-105°C so thatmoisture contents were reduced to a very low level, and reproducibleproperties could be assured. The drying also served toremove most of the volatile oils or waxes, which are knownto influence burning rates. All measurements were duplicated.Each series of tests was completed during a single afternoon toensure standard conditions, i.e., the temperature of the day,and relative humidity were not variables. For the same reason,all subsequent checks, on other days, were carried out onall samples.To obtain quick and uniform ignition, 0.25 ml of acetonewas introduced into a small cone of filter paper placed ontop of the sample at the center, and a burning match wasquickly thrown into the cone. The resulting flame spread intothe fuels, which ignited from the top and burnt downwards.To haye some basis of comparison, crumpled balls of dry(ashless) filter paper were also burnt in the basket. The naturalfuels used were collected in autumn from the forest floor, thosetested being: red pine, white pine, white birch, red oak andpoplar (from two different sources). Badly fragmented samplesof jack pine and white spruce were also available, but theycould not strictly be compared with the other samples, sincefragmentation made their packing very different. Nevertheless,a few representatiye measurements were carried out with thesefuels.Typical traces may be seen in Fig. 1, which shows resultsfor poplar and red pine. There are considerable differences inmaximum burning rate — that for red pine being 39 g/min.,and that for poplar 17 g/min. Maximum burning rates for allspecies studied are given in Table 1 (see Column II), togetherwith average burning rates up to the time when two thirds ofeach sample have been consumed (Column III). The approximateweight of the residue remaining when burning in thebasket is finished, is also given (Column IV).The major aim of these experiments was to obtain comparativevalues of maximum burning rates, when the fuelswere fairly closely packed within the basket. But, because ofCEw5 10 15WEIGHT LOSS (g)Figure 1. Traces showing burning rates of red pine and poplar.31

the somewhat confined nature of burning, ashing of the sampleswas usually incomplete, and significant amounts of charred,carbonaceous material remained. Thus, to derive a more representativemeasure of residual material, small, well aeratedsamples were burnt over an open flame, and the remains collectedand weighed to obtain "ash", or the percentage of inorganicresidue which was not consumed (c.f., Table 1, ColumnI), An alternative method would have been to ash the fuels ina dish over a burner; however, as the equipment needed wasnot ayailable, the above procedure was adopted. It may beseen that, as the ash content of the fuels rises, the flammability,or burning rate, falls. Thus, burning rates decrease in the ordershown in Table 1 (from red pine to white birch), and correspondinglythe ash content of the fuels increases (6 1/2 % for redpine to 15% for white birch). Even the fragmented samplesshow the same typical behavior for pack pine, despite its "closepacked"arrangement, burns quite well, whereas white spruce,with a much higher inorganic content, does not.TABLE 1Burning rates and ash contents of sample fuelsIResidual ashon "completecombustion"(%)IIMaximumburningrate(g/min)IIIAverageburningrate(g/min)IVResidueinbasket(g)Fuel SampleFilter paper — >35 20 nilRed pine 6-1/2 35-40 —27 2White pine 9 25 12 4Poplar (fromChalk River) 10 19 11 4White birch 15 15-20* 10 4-1/2Fragmented SamplesJack pine 11 15 9 4White spruce 17 5

Near the mine, most eastern white pine are scattered, 200-to 300-year-old veterans. From data in Table 1 and an estimatedfrequency of 0.5 pine per acre there would be 235 deadpine in damage class 3 (all white pine dead) and 180 in damageclass 4 (white pine affected). Another 135 trees have thin,yellow crowns and further mortality is expected. Incrementcores from a few veteran white pine indicated that as muchas 80% of some trees could be free of decay. Since they arehighly susceptible to injury from S02, the prompt removal ofany economically valuable stems should be considered.Further mortality can be expected with continued exposure.The few remaining spruce and balsam fir in damageclass 1 will decline as will an increasing number of the moresusceptible species farther from the source. Additional lossesinclude the reduction of increment in the living but affectedtrees, and reduced stand values through changes in stand composition.This will continue to be a problem until the fire isextinguished and the release of SO, stopped, or until the SO2is diluted by dispersion to non-toxic levels during the growingseason.—G. A. Van Sickle, Maritimes Forest Research Centre,Fredericton, N.B.SOILSBiometer Flask for Determining Microbiological Respirationin Forested Soils.—Field measurements of soil respiration,which include microorganism, animal and root activity, generallyoverestimate microbial activity in the soil. Three aerationsystems, continuous, intermittent and static, have been used inthe laboratory to determine soil respiration in the absence ofroot activity. For the latter two systems, a variety of biometerflasks have been deyeloped (Bartha and Pramer, Soil Sci. 100:68-70, 1965; Nommik, Soil Sci. 112: 131-136, 1971). Theseflasks are expensive to purchase or construct (approximately$10-15). All systems use ground or extensively disturbed samples,which lead to increased respiration rates (Webley, J. Agr.Sci. 37: 249-256, 1947) and inaccurate measurement of microbiologicalactivity as it exists within the undisturbed field soil.The flask described herein is inexpensive (approximately $l.35)and allows the use of samples which have undergone a minimumof disturbance.The biometer flask (Fig. la) is a one-quart, wide-mouthmason jar with a plexiglass lid. The lid seals the containerand holds the vial with alkali. Alkali is introduced and remoyedthrough a plastic syringe and needle held in place by a #00rubber stopper. A three-way plastic aquarium valve is includedso tha the system may be flushed with CO 2-free air at selectedintervals, generally every 14 days, for long-term incubations.The alkali must be removed during this procedure.32457 — Monthly Research Notes — Eng. GAL 4Samples are collected in the field with a 5-cm core sampler(Burkard Mfg. Co. Ltd., Rickmansworth, England) and placeddirectly into the glass sample-holder and transported in a coolerto the laboratory. Sample and sample holder are placed in themason jar; the closure with alkali vial is secured in place witha metal-O-ring and the alkali is introduced. The complete systemis then incubated at the soil temperature present in thefield at the time of sampling (Fig. lb).Sample moisure content is determined following the incubationperiod. In this way, sample disturbance and pretreatmentis kept to a minimum.Calculations of respiration rate are based upon the quantityof organic matter (weight loss on ashing oven-dry samples)present in each soil core. This reduces variation between samplestaken from the same plot. Averaged values for eachsample area are converted to grams CO, respired/meter2/hr.A 75-day incubation experiment was conducted to determinethe minimum time required for maximum differencesFigure l. (a) Components of biometer flask. A. 10 cc plasticLuer lock syringe. B. 16G 1 1/2 disposable hypodermicneedle. C. #00 rubber stopper. D. 3.18 mm(1/8") O.D. tygon tubing. E. Metal-O-ring. F. Plasticaquarium valve. G. Lid constructed from 1.59 mm(l/16") clear plexiglass and quartered 3.18 mm(l/8"). H. Plastic vial. Lily #3/4 SP. I. Rubber-oring.J. 1 quart wide-mouth mason jar. K. Glasssample holder and sample.between sample areas to become evident. Twenty-four coreswere collected (March, 1972) from each of control and ureafertilized plots (448 kg N/ha applied March, 1971) underDouglas-fir and incubated at 13 C. After removing the alkali,the system was flushed with CO2-free air every 14 days. Statisticalanalysis of data (Fig. 2) indicated that a significantdifference (P=0.05) in respiration rates was detectable after 2weeks, and this difference was maintained for the duration ofthe incubation. At 4 weeks, respiration rates were significantlydifferent at the 1% level. This would suggest that measurementof respiration rate should be performed over a 4-week incubationperiod.In a second experiment, respiration rates determined inthe field and laboratory were compared by collecting cores (14)from each of three plots on the day the field rates were determined,using the method of Lieth and Quelette (Can. J. Bot.40: 127-139, 1962). The cores were incubated at the same temperature(10 C) as the field soil at the time of sampling. Sincethe respiration rates determined in the laboratory exclude rootrespiration, the difference between laboratory and field values(Table 1) should represent root respiration. In this case, rootrespiration accounts for 60-75% of the total field respiration.Rieners (Ecology 49: 471-483, 1968) has suggested that rootrespiration may represent two-thirds of the field measured soilrespiration in Minnesota forests. This comparison would suggestthat the laboratory determined respiration values are infact a reasonable measure of microbiotic activity as it existedin the field.Maximum respiration rates of 0.25 gm and 0.10 gm CO2/meter2/hr were obtained for the March and mid-July samp-33

Figure 1. (b) Assembled flasks within incubator.ct 30200

ecent publicationsSEPTEMBER - OCTOBERArnott, J. T. 1973. Evolution of the styroblock reforestation concept in British Columbia.Commonw. For. Rev. 52(l):72-78.Bailey, G. R. 1973. Lumber grade recovery from straight aspen logs. For. Prod. J. 23(4) :47-54.Basham, J. T. 1973. Heart rot of black spruce in Ontario. I. Stem rot, hidden rot, and managementconsiderations. Can. J. For. Res. 3:95-104.Carrow, J. R., and R. E. Betts. 1973. Effects of different foliar-applied nitrogen fertilizers onbalsam woolly aphid. Can. J. For. Res. 3:122-139.Chalupa, V., and D. J. Durzan. 1973. Growth and development of resting buds of conifersin vitro. Can. J. For. Res. 3:196-208.Chow, S. 1973. Softening temperatures and durability of wood adhesives. Holzforschung.27(2):64-68.Collis, D. G., and J. W. E. Harris. 1973. Line-throwing gun and cutter for obtaining branchesfrom tree crowns. Can. J. For. Res. 3:149-154.Dorworth, C. E. 1973. Sequence of formation and resin content of scleroderris cankers.Can. J. For. Res. 3:161-164.Durzan, D. J. 1973. The metabolism of 1'C-urea by white spruce seedlings in light and darkness.Can. J. Bot. 51:1197-1211.Durzan, D. J., J. Pitel, A. J. Mia and P. K. Ramaiah. 1973. Metabolism of uracil by germinatingjack pine seedlings. Can. J. For. Res. 3:209-221.Edwards, D. G. 1973. Effect of a soil wetting agent on germination of four important BritishColumbia conifers. For. Chron. 49 (June).Edwards, D. G. W., and P. E. Olsen. 1973. A photoperiod response in germination of westernhemlock seeds. Can. J. For. Res. 3:146-148.Eis, S. 1973. Cone production of Douglas-fir and grand fir and its climatic requirements.Can. J. For. Res. 3:61-70.Endean, F., and D. Hocking. 1973. Performance after planting of four types of containergrownlodgepole pine seedlings. Can. J. For. Res. 3:185-195.Evans, David. 1973. The stages of. Erannis vancouverensis (Lepidoptera: Geometridae) andlife history notes. Can. Entomol. 105:605-612.Funk, A. 1973. Microlychnus gen. nov., a lichenized hyphomycete from western conifers. Can.J. Bot. 51:1249-1250.Funk, A., R. B. Smith and J. A. Baranyay. 1973. Canker of dwarf mistletoe swellings onwestern hemlock caused by Nectria fuckeliana var. macrospora. Can. J. For. Res. 3:71-74.Grant, G. G., and John L. Eaton. 1973. Scent brushes of the male tobacco hornworm Manducasexta (Lepidoptera: Sphingidae ) . Ann. Entomol. Soc. Amer. 66 (4 ) : 901-904.Hatton, J. V., and J. L. Keays. 1973. Relationship of pulp yield with KMnO4 No. and KappaNo. for kraft pulps. III. Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco.] Pulp Pap.Mag. Can. 74(5):T162-T166.Hedlin, A. F. 1973. Spruce cone insects in British Columbia and their control. Can. Entomol.105:113-122.Heger, L. 1973. Effect of index age on the precision of site index. Can. J. For. Res. 3:l-6.Hunt, K., and J. L. Keays. 1973. Short-rotation trembling aspen trees (Populus tremuloidesMichx.) for kraft pulp. Can. J. For. Res. 3:180-184.Jeglum, J. K. 1973. Boreal forest wetlands, near Candle Lake, central Saskatchewan. Part II -Relationships of vegetational variation to major environmental gradients. Musk-Ox. Pub.12, pp. 32-48.Juneja, S. C., and J. K. Shields. 1973. Increased fungal resistance of wood treated with modifiedurea-based fire-retardant resins. For. Prod. J. 23(5):47-49.Keays, J. L. 1972. The resource and its potential in North America. USDA For. Serv., Gen.Tech. Rep. NC-l. pp. 4-9.(Continued on page 34)

i-monthlyresearchnotesContents of Volume 29Microsporida in spruce budworm.Turpentine oil delays ambrosia beetle attacksToxicological studies upon adult spruce budworm.Variation of the form factorGrowing Fomes annosus sporophoresVol. 29, No. 6, NOVEMBER-DECEMBER, 1973.I+Environment EnvironnementCanada CanadaForestry ServiceService des forêts

i-monthlyresearch notes"A selection of notes on current research conducted bythe Canadian Forestry Service and published under theauthority of the Minister of the Department of theEnvironment. A French edition is published underthe title of Revue Bimestrielle de Recherches".CONTENTS OF VOLUME 29, 1973Armstrong, J. and R. G. Vines. Burning properties of Pagessome Canadian forest fuels 31-32Bhure, N. D. Effects of different phosphatic fertilizerson the growth of spruce seedlings in a greenhouse 20-21Boudoux, Michel. Variation of the form factor as afunction of tree dimensions 37-38Cameron, Margaret D. (see Eidt and Cameron)Carrow, J. R. Establishment and survival of balsamwoolly aphid on second growth Amabilis fir atintermediate elevations 10-11Cerezke, H. F. Some parasites and predators of Hylobiuswarreni in Alberta 24-25Clark, R. C., L. J. Clarke and K. E. Pardy. Biologicalcontrol of the European spruce sawfly in Newfoundland2-3Clarke, L. J. (see Clark, Clarke and Pardy)Dangerfield, J. A. and P. E. Olsen. Biometer flask fordetermining microbiological respiration is forestedsoils 33-34Dobbs, R. C. and R. G. McMinn. The effects of sitepreparation on summer soil temperatures inspruce-fir cutovers in the British Columbia interior 6-7Eidt, D. C. and Margaret D. Cameron. Effect of coldtreatment on post-diapause spruce budworms 11-12Evans, David. Survival of European pine shoot mothon cut Christmas trees 9Fraser, H. S. and E. P. Swan. 19-Norisopirama-8(14),15-dien-3-one in Thuja plicata bark 12-13Fraser, H. S. and E. P. Swan. Isolation of a-Atlantonefrom the heartwood extractive of alpine fir 13Funk, A. Liquid cultures in polythene bags 25Gray, T. G., R. F. Shepherd and C. S. Wood. Blackheadedbudworm egg counts, a hot-water technique 29Huntley, G. D. (see Kondo and Huntley)Ilnytzky, S. Evaluation of residual toxicity of six insecticidesfor control of sitka spruce weevil 9-10Ilnytzky, S. and Jack R. Sutherland. Corky rootdisease of Douglas-fir seedlings: Post-plant nematicidetrials to control Xiphinema bakeri 18-19Kondo, E. S. and G. D. Huntley. Smaller Europeanelm bark beetle found in Ottawa 36Little, C. H. A. (see Shaw and Little)Lock, W. (see Sutherland, Sluggett and Lock)Logan, K. T. Temporary stimulation of photosyntheticrate by a short photoperiod 1-3Logan, K. T. Height growth of white spruce transplantedfrom BC/CFS styroblocks 7McMinn, R. G. (see Dobbs and McMinn)Morgan, M. G. (see Shaw and Morgan)Muir, J. A. Lodgepole pine dwarf mistletoe on Douglasfirin AlbertaNijholt, W. W. Ambrosia beetle attacks delayed byturpentine oilOfosu-Asiedu, A. (see Smith and Ofosu-Asiedu)Olsen, P. E. (see Dangerfield and Olsen)Pardy, K. E. (see Clark, Clarke and Pardy)Pollard, D. F. W. Effect of age on the sensitivity ofwhite spruce seedlings to a dormancy-inducingtreatment 27Pollard, D. F. W. (see Teich and Pollard)Raske, A. G. Differences between two species ofbirch in attack and susceptibility to defoliationby the birch casebearer 17-18Raske, A. G. Relationship between felling date andlarval density of Monochamus scutellatus 23-24Reynolds, G. Growing Fomes annosus sporophoresfor a continuous supply of basidiospores 38Scarratt, J. 11. Containerized seedlings: relation betweencontainer size and production period 4-6Shaw, D. D. and M. G. Morgan. A testis-samplingtechnique for holo- and hemi-metabolous inserts 17Shaw, G. G. and C. H. A. Little. Dispersal of secondinstar spruce budworm 30-31Shaw, D. D. and M. G. Morgan. Toxicological studiesof some insecticides upon adult spruce budworm 36-36Shepherd, R. F. (see Gray, Shepherd and Wood)Sluggett, L. J. (see Sutherland, Sluggett and Lock)Smith, Roger S. and A. Ofosu-Asiedu. Degradation ofarabinose in wood attacked by thermophilic fungi 3-4Stanek, W. Comparisons of four methods of pH determinationin peat soils 15Sullivan, C. R. (see Wallace and Sullivan)Sutherland, Jack R. (see Ilnytzky and Sutherland)Sutherland, Jack R., L. J. Sluggett and W. Lock. Associationof some physical and chemical propertiesof nursery soils with corky root disease 19Swan, E. P. (see Fraser and Swan 12-13,13)Szabo, T. (see Wass and Szabo)Teich, A. H. Height, growth and survival of northernwhite spruce provenances at Chalk River, Ontario 26-27Teich, A. A. and M. A. K. Khalil. Predicting potentialincrease in volume growth by progeny testingwhite spruce plus trees 27-28Teich, A. H. and D. F. W. Pollard. Rapid-growingprecocious white spruce provenances 13-14Van Sickle, G. A. Chemotherapy on sweetfern blisterrust cankers 20Van Sickle, G. A. Forests affected by sulphur dioxide innortheastern New Brunswick 32-33Viidik, Paul. The effect of squirrel damage on Norwayspruce (Picea abies (L.) Karst.) 14Vines, R. G. (see Armstrong and Vines)Wallace, D. R. and C. R. Sullivan. First successfultotal laboratory development of eggs of the Europeanpine sawfly 3Wass, E. F. and T. Szabo. Estimating annual heightgrowth by the internode method 1Wilson, G. G. Incidence of Microsporida in a fieldpopulation of spruce budworm 35-36Wood, C. S. (see Gray, Shepherd and Wood)Zalasky, H. Brachiate tracheids in deformed wood ofAbies 23ENTOMOLOGYIncidence of Microsporida in a Field Population of SpruceBudworm.—The spruce budworm [Choristoneura fumiferana]is naturally infected with a wide variety of pathogens. Included25-26 are viruses, fungi, bacteria and microsporida. Studies onMicrosporida affecting spruce budworm have been largely con-36 fined to the laboratory.During the summers of 1971, 1972, and 1973 a populationof spruce budworm in Parkinson Township, Ontario, was examinedfor the presence of Nosema fumiferanae, a common protozoanparasite of the insect. Samples were collected from35

"spruce and balsam fir at various periods throughout thesummer. A sample consisted of 12-15 branch tips cut fromthe host tree, which were examined in the laboratory and thespruce budworm removed, A final sample was taken in thefield with a beating mat after 80-90% of the budworm hadpupated.It was found that there is a general build-up in the incidenceof the microsporidian parasite as the budworm infestationpersists. This was also demonsrtated by Thomson (Can.Dep. Agric, Bi-Mon. Prog. Rept., 16(4):1, 1960) for N.fumiferanae in a population of spruce budworm in the UxbridgeMunicipal Forest, Ontario. The incidence of microsporidaalso increases with age of the larvae during the summer; ahigher percentage of the sixth-instar were infected with N. fumiferanaewhen compared to the other instars (Table 1). Thisprobably resulted from a natural spread of the pathogen duringthe summer; however it is also possible that some light infectionmay have been overlooked in the younger larvae. Viablespores are present in regurgitated fluids and frass of infectedinsects. Larvae killed by the parasite contain millions ofspores (Thomson, Can, J. Zool. 36: 309-316, 1958; Wilson,Ph.D. Thesis, Cornell University, Ithaca, New York, 1973).Spores from these sources may be dispersed by various abioticand biotic factors to other budworm larvae in the population,TABLE 1Percentage microsporidian infection in spruce budworm larvae collectedin Parkinson township during 1971, 1972, and 1973Year CollectiondatePredominateinstarsPercent larvalinfection.1971May 27June 32-34-532.622.4June 10June 176650.640.0May 243-437.0May 31433.31972 June 7533.3June 14640.7June 22641.6May 103-467.01973 May 23466.8June 20682.0Each percentage based on 80-200 examinations.• As indicated in Table 2, those larvae remaining after80-90% of the budworms have pupated have a high incidenceof microsporida. It is possible that most of these larvae arestragglers due to infection by N. fumiferanae. The resultsfrom the examination of the insects in these collections werea further indication- of the increasing levels of- microsporidatoward the end of the budworm season.TABLE 2Percentage of spruce budworms infected with- microsporida based on abeating mat sample taken after 80-90% of the budworms had pupatedin Parkinton Township1972 1973Larvae infected66.6% (18 87.5% (40)Prepupae and pupae infected46.6% (75 ) 81.4%(70)(—)": number of insects examined.An examination of the budworm population in 1974should indicate whether this high level of microsporidian infectionhas any effect on reducing the level of the infestation.—G. G. Wilson, Insect Pathology Research Institute, Sault Ste.Marie. Ont.Ambrosia Beetle Attacks Delayed by Turpentine Oil.—Because certain monoterpens have a repellent effect on theambrosia beetle [Trypodendron lineatum .)] (Moeck,Can. Entomol.: 102:985-995, 1970) a test was conducted in aforested area at Lake Cowichan, B.C. during mid-June 1970to determine whether such naturally occurring volatiles couldretard beetle attack. -Four Douglas-fir bolts (.75 m long) were cut from eachof two trees and placed on end in a row 2 m apart, alternatingcontrol and treated bolts. Two bolts from each tree were usedas controls. The other bolts were brush-wetted with commercialturpentine oil (distillate of a mixture of mainly monoandditerpenes). -After 3 days, the beetles were crawling on and burrowinginto the control bolts; none were seen on the treated boltsuntil the fifth day, The bark was stripped from all the boltson the sixth day. Table 1 shows the numbers of T. lineatumattack holes.TABLE 1Numbers of attack holes of Trypodendron lineatum on bolts 5 days aftertreatment with turpentine oilNo. of T. lineatum Attack HolesBolt No.Treated Untreated2300625697349122650720Treatment with turpentine retarded the attack. As theterpenes evaporated, the bolts again became susceptible. Theextent of retardation is apparently related to the rate of evaporationof the effective terpenes. Treated bolt No. 2 was ina shaded area where evaporation was slower than in directsunshine.Trees cut shortly before the flight season are less heavilyattacked than those cut during fall and early winter (Dyerand Chapman, Can. Entomol. 97:42-57, 1965). Whether thisis due to masking, lack of primary attraction or other mechanismis not clear.Further experiments with selected terpenes may identifynaturally occurring retardants. The use of such retardants,probably in combination with stickers, along with water misting(Richmond and Nijholt, Can. For. Serv. Inf. Rep. BC-P-4,1972), and a male-produced pheromone mask (Nijholt, Can.Entomol. 102:894-897, 1970; 105:583-590, 1973; J. H. Borden,personal communication) could provide effective means of logprotection.—W. W, Nijholt, Pacific Forest Research Centre,Victoria, B.C.Toxicological Studies of Some Insecticides upon AdultSpruce Budworm.—The extension of the aerial spray programto include the spraying of adult insects has necessitated anevaluation of the relative toxicides of various insecticides onadult budworm. Preliminary tests, using fenitrothion, phosphamidon,lannate, and pyrethrins, have been made in the laboratory.Diapause-free budworm were reared on synthetic dietto pupation, then pupae were isolated in shell vials untilemergence. The sexed adults (2 days old) were anaesthetizedwith CO2 and tested in replicates of 8 to 12 insects with tworeplicates per dose. Control replicates were dosed with purecyclohexanone solvent. The insecticide was applied betweenthe front coxae using a 0.2- ul capillary tube. Mortality wasassessed after 24 hours. The probit regression lines werecalculated by program on a Wang 700 calculator and werecorrected for natural mortality.Phosphamidon was the most effective insecticide at bothLD50 and LD95 values (Table l), which agrees with , preliminarystudies under field conditions (E, G. Kettela, personalcommunication). The slopes of the probit lines for the threesynthetic compounds are very similar, being almost parallel.However, the slope of the pyrethrin line is much steeper (Fig. l)giving an LD95 value comparable with the other three, eventhough its LD50 is 3.5 times less than that for phosphamidon.This may prove to be of considerable importance in the assessmentof the pyrethrin group as potential field compounds. Theefficacy of pyrethroids can be greatly improved by mixingthem with synergists like sesame oil and iperonyl butoxide.36

TABLE 1LD50 and LD95 values (in ml/ml or g/ml of cyclohexanone solvent) calculated after topically treating adult budworm of known ageRelative potence.SlopeLD50LD95Insecticide L050 LD95Phosphamidon (92% a.i.) 0.00028 ml/ml 0.00126 ml/ml 2.54 l.0 1.0(0.00034 g/ml) (0.00154 g/ml)Fenitrothion (95% a.i ) 0.00043 ml/ml 0.00171 ml/ml 2.77 l.54 1.47(0.00057 g/ml) (0.00226 g/ml)Lannate (90% a.i.) 0.00063 g/ml 0.00261 g/ml 2.67 2.25 l.69Pyrethrins 1 & II (20% a.i.)b 0.00102 ml/ml 0.00260 ml/ml 4.07 3.64 1.69LD50 or 95 of InsecticideRelative potence =LD50 or 95 of Phosphamidon" Pyrocide 175.form factors were not distributed at random around a meanvalue, but were significantly related to some specific parametersof each tree.This stand was located about 40 miles (64 km) north ofQuebec City. Its main characteristics are given in Table l.In the interior of the stand 40 trees were selected at randomand felled for complete measurement. Their breast heightform factor was computed, i.e. the relationship between thetotal volume of the tree and a cylinder of same height, thediameter of which would be equal to the dbh of the tree. Thetotal volume of each tree was calculated by cutting its steminto sections 1 foot (30.48 cm) long and calculating the volumeof each with Newton's formula. For the sample studied, theform factors ranged from 0.48 to 0.62 with an average of0.55 ± 0.032.LOG DOSEFigure l. Log dosage - probit mortality regression lines forthe four insecticides tested against adult sprucebudworm.For instance, a 1:10 mixture of pyrethrins and piperonyl butoxidereduced the LD50 of pyrethrins alone by a factor of 4.6when applied to Sitophilus granaria (Parkin and Lloyd, J. Sci.Food Agric. 11:471-477, 1960). In the present case, if theaddition of piperonyl butoxide reduced the LD50 value tothat obtained for phosphamidon and if the slope remainedthe same, then the LD95 value of pyrethrins would be 1.7times more effective - an improvement which would warrantits use in the spray program.-D. D. Shaw and M. G. Morgan,Maritimes Forest Research Centre, Fredericton, N.B.MENSURATIONVariation of the Form Factor as a Function of TreeDimensions.-Using the form factor in formulas of the type:V = fGh (l)(where V represents the total volume, f the mean form factor,G the total basal area, and h the mean height of the stand)is based on the assumption that, for a given tree species in ahomogeneous site, there is a mean form factor representativeof the stand. In other words, variations observed between thismean form factor and the form factors of each tree occurstrictly at random. It is well known that such is not the casefor some stands (see, for instance, Prodan M., 1965; Holmesslehre,p. 191), though such a mean factor exists within evenagedstands, according to other authors (Pardé J., 1961; Dendrométrie,p. 236). Without the purpose of decisive argument,we noted during a mensuration study conducted in a natural,even-aged stand of balsam fir [Abies balsamea] that individualTABLE 1General characteristics of the standNo. of stems per acre 1,200Mean diameter (dbh)15,98 ± 2.09 inchesMean total height146,50 11.28 feetMean age,63 ± 10 yearsMean form factor calculated 0.55 ± 0.032at the dbh2Standard deviation of distribution, calculated from a random samplingof 300 stems.± Standard deviation of the distribution brought about by the 40studied samples.Besides the form factor, the diameter at 4.5 feet (l.37 m)(dbh), age, mean rate of radial increment and total heightwere calculated or measured on each tree.Values of the correlation factors existing between thedifferent variables are given in Table 2. It is obvious that theform factor is independent of the age of the tree (r = -.028)but is, on the other hand, strongly related to both dbh andtotal height (r -.579++ and -.468++, respectively).The significant relationship existing between the form factorand mean increment rate (r -.574++) is not surprising,inasmuch as the mean increment rate is nothing else than theradius/age ratio, and age is not correlated with form factor(r = -.028).TABLE 2Matrices of correlation coefficients for the five factors considered (N=40)X1 X2 X3 X4 X5Age X1 1 -.194 .326+ .321+ -.028Mean increment X2 1 .846++ .622-H- -.574++Diameter + (dbh) X3 1 .773++ -.579+Total height X4 1 -.468++Form factor X5: significant at 0.05 level.++ : significant at 0.01 level.The regression equations for our variables are as follows:X5 = .6034 - .0090 X3 r = -.579++ (2)X5 .6122 - .0014 X4 r = -.468++ (3)X5 = .6065 - .0084 X3 - .002 X4 F 9.37++ (4)37

Where X3 is mean dbh; X4 is total height; X5 is form factor.It is X3, the dbh, that accounts for most of the variationobserved in form factors. A graphical representation of thatrelationship is given in Figure 1 (equation 2).Diameters and heights being strongly correlated (r =.773++), it is evident that equation (4) does not provide anyadditional information. It actually appears that the abovethree-equation system should be expounded as follows: thevariation of the form factor within the natural homogeneousstand studied is related to a "size factor", i.e. the taller theFORM LL0.62 =.80335 -.0089980.60 00 0 00.580.56r = -.579Growing Fomes annosus Sporophores for a ContinuousSupply of Basidiospores.—It is desirable to use basidiosporesin studies of the biology and control of Fomes annosus asthey are primarily responsible for establishing new infectioncenters. Ready access to a sufficient and continuous supplyof these spores has not always been possible. For example,in drier regions such as California, sporophore production israre (Bega, Phytopathology, 53:1120-1136, 1963), and in easternCanada, sporophores are inactive during extreme summerand winter conditions (Punter, Root diseases and soil bornepathogens. Univ. Calif. Press, Berkeley, pp. 156-160). Basidiosporesare produced throughout most of the year on the southcoast of British Columbia (Reynolds, Bi-Mon. Res. Notes22(4):6-7, 1966), but the time expended in travel to collectthem is considerable. A quick and easy method of growingsmall sporophores has been outlined by Boyce, Jr. (Plant Dis.Rep. 46:1, 1962). The following method was developed bythe author to promote the growth of large sporophores (20 x 7cm) for the prolific production of basidiospores over a longperiod of time. The method also lends itself to the study ofconditions conducive to sporophore production and spore liberationin situ.Hemlock bolts [Tsuga heterophylla (Raf.) Sarg.], 30-40cm in diameter and 45 cm long, with well-developed F. annosusdecay, were cut in the forest and brought to the laboratory.The logs were elevated above a greenhouse bench on 10-cmblocks, exposed to natural lighting only and covered with athick layer of moss. An automatic spray misting system keptthe moss and logs moist. Temperatures within the compartmentvaried from 10-25 C. Sporophores began to develop onthe undersides and ends of the logs in approximately 10 months(Fig. 1).0.5400,520.500 000.480 3 4 6 7 8 9 10 11 xDIAMETER IN INCHES (dhb)8 10 13 15 18 20 23 25 28DIAMETER IN CENTIMETERSFigure 1. Relationship between the dbh and form factor.tree is, the lower its form factor tends to be. Such an observedvariation is far from being negligible: for 2-10 in. diameters,the form factor decreased from .62 to .52, and such a decreasemay lead to a difference of about 20% over or under incalculating the total volume. It should be noted that the resultsherein presented represent only an isolated instance which furtherstudies will confirm or invalidate. As a matter of fact,a more general study dealing with a very large number ofstands (over 6000 trees) is being conducted to determine thepercent of variation of the form factor that would be relatedto the size of the tree.If such a rate was to prove significant in numerousinstances, it might be advisable to question the validity of fastcubing formulas, such as equation (1), which assumes the existenceof a mean form factor constant inside a stand homogeneousin other respects.—Michel Boudoux — LaurentianForest Research Centre, Ste. Foy, Qutbec, P.Q.PATHOLOGYFigure l. Moss-covered log section supporting Fomes annosussporophores.Variation in formation time of new, tube-layer structuresamong the sporophores was such that there was an abundantand continuous supply of spores; some sporophores are nowin their fifth year of spore production.Sporophores were also produced under controlled temperature,humidity and light. Logs, similar to those describedabove, were placed on benches in a room having a constanttemperature of 12 C, a relative humidity of 80% and continuouslight of 4-20 fc. The moss and logs were thoroughlywetted when placed in the room and, because of the lowevaporation rate, have required wetting only twice a month.Sporophore development began in 8 months. Liberation ofviable spores has at least equalled that obtained from thesporophores grown in the greenhouse.—G. Reynolds, PacificForest Research Centre, Victoria, B.C.ErratumVol. 29, page 26, column I, second paragraph, should read"In western Alberta . . ."(Continued from back cover)Miller, D. G. 1973. Further report on combining radiofrequencyheating with kiln-drying. For. Prod. J. 23(7) :T31-T32.38

Palka, L. C. 1973. Predicting the effect of specific gravity,moisture content, temperature and strain rate on the elasticproperties of softwoods. Wood Sci. Technol. 7:127-141.Payandeh, Bijan, Robert B. Pope and David P. Paine. 1973.Bias from Photo intensity. Photogram. Eng. XXXIX(5):473-476.Raske, A. G. 1973. Tetropium parvulum elevated to speciesrank and contrasted to T. cinnamopterum in morphologyand host preference (Coleoptera: Cerambycidae). Can.Entomol. 105:745-755.Raske, A. G. 1973. Notes on the biology of Tetropium parvulum(Coleoptera: Cerambycidae) in Alberta. Can.Entomol. 105: 757-760.Raske, A. G. 1973. Taxonomic relationship between Monochamusscutellatus and M. oregonensis (Coleoptera. Cerambycidae).Can. Entomol. 105: 795-806.Sahota, T. S. 1973. Yoke deposition in Douglas-fir beetleoöcytes: possible role of RNA synthesis in the follicularepithelium. J. Insect Physiol. 19:1087-1095.Sahota, T. S., and A. Ibaraki. 1973. Yolk deposition in theDouglas-fir bark beetle, Dendroctonus pseudotsugae(Hopk.): the significance of physiological state of oöcytes.Can. J. Zool. 51:659-661.Sayn-Wittgenstein, L., and A. H. Aldred. 1973. Large-scaleaerial photography for tropical forestry. In Economic forestière.Faculté des sciences agronomiques de l'étatGembloux (Belgique). (Sept.) 1972.Shrimpton, D. M. 1973. Age- and size-related response oflodgepole pine to inoculation with Europhium clavigerum.Can. J. Bot. 51:1155-1160.Sims, H. P., and C. H. Buckner. 1973. The effect of clearcutting and burning of Pinus banksiana forests on thepopulations of small mammals in southeastern Manitoba.Amer. Midland Natur. 90(1) :228-231.Sinerlis, E. 1973. Pathogenicity tests of some discomycetesoccurring on conifers. Can. J. For. Res. 3:7-16.Smirnoff, W. A. 1973. Results of tests with Bacillus thuringiensisand chitinase on larvae of the spruce budworm.J. Invertebr. Pathol. 21:116-118.Smirnoff, W. A., and B. Bernier. 1973. Increased mortality ofthe Swaine jack-pine sawfly, and foliar nitrogen concentrationsafter urea fertilization. Can. J. For. Res. 3:112-121.Smirnoff, W. A., A. P. Randall, R. Martineau, W. Haliburtonand A. Juneau. 1973. Field test of the effectiveness ofchitinase additive to Bacillus thuringiensis Berliner againstChoristoneura fumiferana (Clem.). Can. J. For. Res.3:228-236.Smith, S. G. 1973. Chromosomal polymorphism and inter-relationshipsin Pissodes weevils: additional cytogenetic evidenceof synonymy. Can. J. Genet. Cytol. 15:83-100.Smith, Stanley G. 1973. Karyotype analyses of Pissodesweevils: evidence for two additional putative taxa. Can.J. Genet. Cytol. 15:215-222.Smith, Roger S., and Lee R. Gjovik. 1973. Interlaboratorytesting of wood preservatives using ASTM Dl413-61.Wood and Fiber. 4(3):170-178.Smith, R. B., J. A. Baranyay and E. V. Morris. 1972. Threenew host records for dwarf mistletoes in British Columbia.Can. Plant Dis. Surv. 52(4):137-138.Stanek, W. 1973. Comparisons of methods of pH determinationfor organic terrain surveys. Can. J. Soil Sci. 53:117-183.Stanek, W., and L. Orloci. 1973. A comparison of Braun-Blanquet's method with sum-of-squares agglomeration forvegetation classification. Vegetatio. 27(4-6) :323-345.Still, G. N., and H. R. Wong. 1973. Life history and habits ofa leaf miner, Cameraria macrocarpae, on bur oak inManitoba (Lepidoptera: Gracillariidae). Can. Entomol.105:239-244.Strang, A. M. 1973. Succession in unburned subarctic woodlands.Can. J. For. Res. 3:140-143.Strunz, G. M., and A. S. Court. 1973. Total synthesis of racemiccryptosporiopsin. J. Amer. Chem. Soc. 95:3000-3002.Sullivan, C. R., and D. R. Wallace, 1972. The potential northerndispersal of the gypsy moth, Porthetria dispar (Lepidoptera:Lymantriidae). Can. Entomol. 104:1349-1355.Sutherland, Jack R., and L. J. Sluggett. 1973. Corky rootdisease of Douglas-fir: relation to Xiphinema bakerinematodes to symptom severity, and observations on seedlingtissue and soil nutrients. Can. J. For. Res. 3:299-303.Sutherland, Jack R., L. J. Sluggett and W. Lock. 1972. Corkyroot disease observed on two spruce species and westernhemlock. Tree Planters' Notes. 23 (4 ) : 18-20.Sutton, R. F. 1973. Seismic and resistivity exploration of soilsand shallow bedrock in forestry research and management.For. Chron. 49 (June).Troughton, G. E., and S. Chow. 1973. Heat-induced colorintensitychange in coastal Douglas-fir and white spruce.Wood and Fiber. 4(4):259-263.Unligil, H. H. 1972. Penetrability and strength of white spruceafter ponding. For. Prod. J. 22(9):92-100.Unligil, H. H. 1971. Penetrability of white spruce wood afterwater storage. J. Inst. Wood Sci. 5(6) :30-35.Van Sickle, G. A. 1973. A survey of production losses dueto witches' broom of blueberry in the Maritime Provinces.Plant Dis. Reptr. 57:608-611.Vithayasai, C. 1973. Exact critical values of the Hardy-Weinberg test statistic for two alleles. Commun. Stat.1(3):229-242.Young, Allen M., David Tyrrell and Donald M. MacLeod. 1973.Entomophthora echinospora (Phycomycetes: Entomophthoraceae),a fungus pathogenic on the NeotropicalCicada, Procollina biolleyi (Homoptera: Cicadidae). J.Invertebr. Pathol. 21(1): 87-90.39

ecent publicationsNOVEMBER - DECEMBERAngus, T. A. 1973. Perspectives of biological insect control. Ann. N. Y. Acad. Sci. 217:4-7.Bailey, G. R. 1973. Wood allocation by dynamic programming. Can. For. Serv. Pub. 1321.19 pp.Barton, G. M. 1973. The significance of western hemlock phenolic extractives in .groundwoodpulping. Tappi. 56 (5 ) : 115-118.Basham, J. T. 1973. Heart rot of black spruce in Ontario. II. The mycoflora in defective andnormal wood of living trees. Can, J. Bot. 51:1379-1392.Cameron, J. W. MacBain. 1973. Insect pathology. Annu. Rev. Entomol. 285-306 (Copyright1973).Cech, M. Y. 1973. Are you drying lumber properly? Can. For. Ind. (July).Chafe, S. C. 1970. The fine structure of the collenchyoota cell wall. Planta (Berl.) 90:12-21.Chafe, S. C., and A. B. Wardrop. 1970. Microfibrillar orientation in plant cell walls. Planta(Berl.) 92:13-24.Chafe, S. C., and A. B. Wardrop. 1972. Fine structural observations on the epidermis. I. Theepidermal cell wall. Planta (Berl.) 107:269-278.Chafe, S. C., and A. B. Wardrop. 1973. Fine structural observations on the epidermis. II. Thecuticle. Planta (Berl.) 109:38-48.Chow, S. 1973. Thermal reactions and industrial uses of bark. Wood and Fiber 4(3):130-138.Cunningham, J. C., J. M. Burke and B. M. Arif. 1973. An entomopoxvirus found in populationsof the large aspen tortrix, Choristoneura conflictana (Lepidoptera: Tortricidae)in Ontario. Can. Entomol. 105:767-773.Dionne, Jean-Claude. 1973. Distinction entre stries glacielles et stries glaciaires. Rev. Geogr.Montr. XXVII(2) :185-213.Dionne, Jean-Claude. 1973. Fentes de cryoturbation fossiles a Arthabaska, Québec. Rev. Géogr.Montr. XXVII (2 ) :190-196.Dionne, Jean-Claude. 1973. Etude morphométrique de galets des formations quaternaires dela région de Riviêre-du-Loup/Trois-Pistoles, Québec. Rev. Géogr. Montr. XXVII(3):139-156.Eis, S., and J. R. Long. 1973. Root pruning in the nursery. Tree Planters' Notes. 24(l):20-22.Gonzalez, A., and B. J. R. Philogène. 1973. Qualitative and quantitative determination of uricacid and allantoin in Neodiprion swainei Midd. Frass. Naturaliste Can. 100:117-122.Griffiths, K. J. 1973. The dispersal of the introduced parasite Lophyroplectus luteator (Hymenoptera:Ichneumonidae) following its release against Neodiprion sertifer (Hymenoptera:Diprionidae) in Ontario. Can. Entomol. 105 : 833-836.Hatton, J. V. 1973. Application of empirical equations to kraft process control. Tappi. 56(8):108-111.Hatton, J. V. 1973. A survey of current practices in liquor analyses in Canadian alkaline pulpmills. Pulp Pap. Mag. Can. 74(5):T170-T173.Hiratsuka, Yasuyuki. 1973. The nuclear cycle and the terminology of spore states in Uredinales.Mycologia. LXV(2) :432-443.Hulme, M. A., and J. K. Shields. 1973. Treatments to reduce chip deterioration during storage.Tappi. 56(8) :88-90.Juneja, Subhash C. 1973. Synergism and fire retardance of wood and other cellulosic materials.Advance. Fire Retardants. Part 2. 3:31-53.Manning, G. H. 1973. Canada's role in future North American forest products markets.For. Prod. J. 23(9):50-54.Marten, Gerald G. 1973. Time patterns of Peromyscus activity and their correlations withweather. J. Mammalogy. 54 (1 ) : 169-188.McNally, J. A. 1973. Logging in the Soviet Union. Pulp Pap. Mag. Can. (Apr. - Aug.).(Continued on page 38)