If you were out in the last few weeks (mid June) you
were treated to the worst infestation of spruce bud worm I have ever
seen here. It was enough to give you the creepy crawlies. Worms hung,
crawled and floated everywhere. We are in very real danger
of losing our entire forest of pine trees to these little buggers. If
you look up you will see that the tops of all the evergreens are now
dead because all the new growth for this year has been eaten by the
worms. Soon the millions of worms will turn into moths and lay more eggs
(up to 150 per moth).
"The
greatest impact from budworm is among suppressed and intermediate trees.
Repeated budworm defoliation causes tree mortality over large areas,
reduction of growth rates and reduced lumber quality. Sustained attack
results in complete defoliation in 4 to 5 years. Once an infestation has
subsided, defoliated trees take several years to regain a full foliage
complement, and therefore radial growth rates require several years to
attain normal growth following defoliation by the budworm. Successive
years of defoliation in stands may predispose trees to other insects and
pathogens. Tree mortality may continue due to root disease, bark
beetles, loss of vigour and other causes."
Quick facts
The western
spruce budworm occurs in coastal and interior British
Columbia south of Quesnel, in the foothills of Alberta and in
the Cypress Hills on the Alberta-Saskatchewan border
The western spruce budworm
feeds on the growing shoots of trees
Early in the growing season,
shoots and needles are encased in silk and turn a distinct
reddish colour by late summer. The tops of some trees may appear
needleless
Most trees survive years of defoliation though
grow slower than non-infested trees and often develop defects
reducing their value as timber
After 4 to 5 years of
persistent and severe defoliation trees usually die, especially
understory trees
