Title

Impact of the Western Spruce Budworm (Lepidoptera: Tortricidae) on Buds, Developing Cones, and Seeds of Douglas-fir in West Central Idaho

Authors

C J. Frank

Document Type

Article

Journal/Book Title/Conference

Environmental Entomology

Publication Date

1987

Volume

16

Issue

1

Abstract

Epidemic levels of the western spruce budworm (WSB), Choristoneura occidentalis Freeman, caused average tree defoliation in west central Idaho to increase from 35% in 1984 to 83% in 1985. Associated with this increase in defoliation was a change in relative stand ranking of defoliation between the 2 yr. WSBwas found to damage all types and developmental stages of reproductive structures of Douglas-fir. Differential selection of feeding sites was observed, with a significantly higher proportion of larvae found in seedcone buds than in pollen-cone buds. Of cones examined, 76% were infested with larvae, with the average percentage of destroyed seeds per tree exponentially related to the average current defoliation of the tree. However, even in heavily defoliated trees, some potentially viable seed remained.

Comments

Originally published by the Entomological Society of America. Abstract available through remote link. Subscription required to access article fulltext.

First Page

304

Last Page

308