Armillaria (Fr. ex. Fr.) is a parasite whose pathogenicity
and role in forest ecosystems often depends upon the
physiological condition of the tree. Therefore, I tested the
frequency and severity of Armillaria ostoyae (Romagn.) Herink
infection among Abies grandis (Dougl.) Lindl., Larix
occidentalis Nutt., Pinus contorta var. latifolia (Engelm.),
Pinus...
The main objective of this thesis was to determine the influence of tree vigor on susceptibility to Armillaria root disease. First, the effect of thinning, fertilizing and pruning on tree vigor of four young Douglas-fir (Pseudo tsuga menziesii var. menziesi,) plantations was explored. Tree vigor was calculated by measuring wood...
Methods used to establish permanent plots in precommercially thinned and unthinned stands to monitor root disease development are described. Plots were established in 22 Armillaria-infested stands in northern Idaho and western Montana. The proportion of trees dead and infected was significantly higher for planted than for natural regeneration at the...
This greenhouse study evaluates the influence of separately and
simultaneously imposed water stress, western spruce budworm (Choristorneura
occidentalis Freeman) defoliation, and inoculation with the root pathogen, Armillaria
ostoyae (Romagn.) Herink, on the growth and biochemical features of Abies .grandis
(Dougl.) Lindi. Seedling biomass, plant moisture status, bud phenology, and
allocation...
White and grand fir are both valuable components of the mixed-conifer stand structure managed for late-successional reserves in central Oregon. However, they are often short-lived species because of high susceptibility to root diseases, defoliating insects, bark beetles, and wildfire. This study focuses on the effects of root diseases caused by...
A root disease evaluation was completed for the Ducharme logging unit near the southeast corner of Flathead Lake. Extensive root disease was found on Douglas-fir throughout the unit. The major pathogen on the site was Armillaria meilea. Black stain (Verticicladiella sp.) was isolated from one tree which was also infected...
