Bagworms, thyridopteryx ephemeraeformis, feed on more than 120 species of trees and shrubs. Including most species of evergreen trees and bushes, conifers, as well as some deciduous plants. Bagworms are small caterpillars that surround themselves with host plant material, creating a bag-like structure that protects them as they feed on leaf tissue.

A bagworm starts its life warm and cozy in the safety of it’s mothers hand made “bag”. With mom nowhere in site, it will leave the bag, string a thin thread parachute and float in the breeze. Now in the best case scenario he lands somewhere far away but thanks to your luck he found your arborvitae! Now what? He eats. Now using leaves, bark, needles, scales and whatever else the tree provides, your new bagworm builds his bag just like his mother before him, all the while devouring your trees foliage.

Now one worm isn’t a problem. Just pluck his pine cone looking bag (a very good camouflage mechanism especially when on an evergreen) and squish it. But beware because one single female lays 500 eggs, and they can strip a tree clean. Once they’re done eating and the females bag is fully constructed, she goes in and stays there. Males, on the other hand, molt into a moth that flies to the females bag and mates. Once her eggs are laid she exits and dies, leaving her bag to be inherited by her babies who stay there all winter to start over again in the spring. Without treatment this cycle continues until there is no foliage left.

Branch Tree & Landscape Service | Contact Us