IntensIve sIlvIculture - Forest Science Labs - Research Network ...

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inoculated seedlings had 40% of their short roots colonized by L. laccata and another 40% by the
native fungi Rhizopogon and Thelephora spp. All mycorrhizae of control seedlings and those
inoculated with P. tinctorius were formed by fungi native to the nursery beds. A significant fungal
treatment effect was detected for shoot height only. Control seedlings were significantly taller
than L. laccata-inoculated seedlings after transplanting.
282. Hunt, J.A. 1995. Commercial thinning a coastal second-growth forest with a Timberjack cut-tolength
system. Forest-Engineering-Research-Institute-of-Canada FERIC TN-235. 14 p.
Keywords: thinning
commercial thinning
economics
tree/stand health
Abstract: In the summer of 1994, after 2 years operation, FERIC monitored a thinning
operation of second-growth forest dominated by Douglas fir [Pseudotsuga menziesii] near
Cowichan Lake, Vancouver Island, to determine productivities, costs and impacts to sites and
residual stands. The thinning treatment was carried out with a Timberjack 1270 harvester and a
Timberjack 910 forwarder.
283. Ingham, E.R. and W.G. Thies. 1997. Changes in rhizosphere microflora and microfauna 10 years
following Douglas-fir live tree injection with chloropicrin or methylisothiocyanate. Canadian-
Journal-of-Forest-Research 27(5): 724-731.
Keywords: tree/stand protection
tree/stand health
soil properties
Abstract: Pseudotsuga menziesii trees in a stand near Apiary, Oregon, were injected in
1981 (age 47 years) with chloropicrin or methylisothiocyanate (MITC) in an effort to control
laminated root rot caused by Phellinus weirii. Soil samples were collected in 1991 from around
structural roots 0.5, 1 and 2 m from the base of injected or non-injected trees. The activity of
fungi and bacteria, total fungal and bacterial biomass, the number of protozoa (flagellates,
ciliates, and amoebae), and the number and types of nematodes were evaluated. Active fungal
biomass was reduced by both chemicals as compared with non-injected trees 10 years after
application. Both active and total bacterial biomass were also significantly lower around roots of
chloropicrin- and MITC-treated trees, as were flagellate numbers. The number of bacterialfeeding
nematodes was decreased around roots of chloropicrin-treated trees, while other
nematode-feeding groups were not changed. The number of root-feeding, bacterial-feeding and
fungal-feeding nematodes were significantly greater around MITC-treated roots, while predatory
nematode numbers were lower, than around control roots. Reduced bacterial and fungal biomass
around MITC-treated trees may be the result, therefore, of increased feeding by nematodes, and
thus MITC-treated trees may benefit from more rapid nutrient-cycling rates but may suffer more
pest damage from root-feeding nematodes as a result of the chemical application. Since many
organism groups were reduced around roots of chloropicrin- and MITC-treated trees, this
suggested possible impacts related to reductions in nutrient cycling rates and production of plantavailable
N around these trees.
284. Jacobs, D.F., R. Rose and D.L. Haase. 2003a. Development of Douglas-fir seedling root
architecture in response to localized nutrient supply. Canadian-Journal-of-Forest-Research 33(1):
118-125.