Douglas-fir trees damaged by tussock moth outbreak
July 23, 2020
MISSOULA -Douglas-fir trees throughout western Montana are being damaged by an outbreak of Douglas-fir tussock moth (DFTM). Damage is particularly notable throughout Missoula, Kalispell and along Flathead Lake. The Montana Department of Natural Resources (DNRC) and the USDA Forest Service are currently monitoring the scope and extent of damage.
DFTM are voracious feeders that can cause alarming damage to trees, but a virus naturally builds up by approximately the third year of an outbreak and controls the caterpillar population. Insects in the highly visible patches are estimated to be i...