Dwarf Mistletoes - Learn Forestry

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to dwarf mistletoes in BritishColumbia are estimated at over3.7 million m3. On addition todwarf mistletoes, only onespecies of true mistletoe,Viscum album L. subsp album,has been recorded on deciduoustrees in Victoria.Hosts and distributionFive species of dwarf mistletoeoccur in British Columbia. Eachdwarf mistletoe does most of itsdamage on a principal host, buteach also parasitises secondaryand occasional hosts.In British Columbia, lodgepolepine dwarf mistletoe extendsfrom the summit of the CoastRange eastwardto beyond the provincialboundary and from theinternational boundary northwardto 57 north latitude.Hemlock dwarf mistletoeexists as three segregates inforest on the seaward side of theCoast Range; one segregateprimarily parasites westernhemlock, another primarily shorepine, and a third primarily occurson mountain hemlock and amabilisfir. Hemlock stands of the interiorwet belt are free of dwarfmistletoe infection.Larch dwarf mistletoe isrestricted to southeastern BritishColumbia in the Osoyoos, UpperCranbrook triangle. It has notbeen found on eastern larch.Stands infested byDouglas-fir dwarf mistletoe arefound only in the Okanagan andSimilkameen valleys and in thecreston area. Isolated infestedstands occur near Lytton,Sicamous and Rossland. Douglas-firin coastal stands have been freeof infection except for oneverified sample found in Chilliwackin 1978.Athough recorded here,the distribution of western dwarfmistletoe, Arceuthobiumcampylopdum, is unknown inBritish Columbia. However, itoccurs in natural ponderosa pinestands within 32km of theinternational boundary near KettleFalls, Washington.2
Generalised life cycle of dwarf mistletoe:A. Needle angles as they affect dwarf mistletoe seed movement.B. A fully developed dwarf mistletoe seedling with holdfast.C. Small branch swelling is the first indication of dwarf mistletoe infection.D. Male (staminate) flowers of dwarf mistletoe.E. <strong>Dwarf</strong> mistletoe seed discharge.3
Page 1: ISBN 0-662-20243-0 Cat. No. Fo 29-6
Page 5 and 6: Some important characteristics of t
Page 7 and 8: Witches’ brooms on lodgepole pine

Dwarf Mistletoes - Learn Forestry

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