The western hemlock looper is a native
defoliator of western hemlock, western redcedar,
interior spruce and Douglas-fir. This
insect periodically reaches outbreak levels
causing severe damage to forests in both
interior and coastal stands in British Columbia.
The Southern Interior Area manages western
hemlock looper damage by monitoring populations
in susceptible stands and when significant
damage is predicted, plans to reduce the impact
of the defoliation through targeted aerial
spraying using the biological insecticide,
Bacillus thruringiensis var. kurstaki (Btk).
This web site provides background information
on the pest and the most current management