Over 10,000 acres of aerially visible western hemlock looper defoliation on grand fir was detected on State and Federal forests of central Idaho in 1972. This is the first report of this insect building up
in Region 1 since a widespread outbreak in 1937-39.
The western hemlock looper has the...
Aerial surveys of the Nezperce National Forest in Idaho revealed 138,692 acres of aerially visible top kill and tree mortality due to repeated defoliation by western spruce budworm, Choristoneura occidentalis Freeman.
A small ground sample indicates that up to 47 percent of the grand fir volume was affected by top...
Published March 1974. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog