Bagworms: How To Get Rid Of Them And What’s Really In The Bag?
You have seen the brown areas on an otherwise evergreen tree, particularly Cedars, and often they are covered with masterly disguised silk cocoons made of the host tree’s leaves. But what is inside the “bag”? It is actually a caterpillar, not a worm, that will eventually become a moth. The caterpillars eat ferociously after hatching from an egg in April, May, and June in Oklahoma, which is when you may see holes in leaf vegetation. They are highly damaging to ornamental trees and can be found on Junipers, all Pines, Cedars, Oaks, Spruce, and Locust trees. If not controlled bagworms will eventually cause the unsightly browning or “bronzing” on the tree and can eventually kill the host tree.
Timing of bagworm control can be very important, and the earlier the trees are treated, the better the result. The caterpillars hatch from April to June and will then begin their feast until July to August, at which time they retreat to pupate inside the camouflaged bag. Ideally chemical treatment is most successful before the bag reaches a half an inch. In later stages chemical treatment can still be successful with alternate chemicals that were applied previously. The caterpillar pupates inside the bag from July to September, at which time only the male moth emerges. He then locates the females who remain inside the bag as a caterpillar, and after mating the male dies. Over winter the female can lay between 100 to 300 eggs inside the bag, where she then dies thus completing the life cycle in late spring when the eggs hatch.
© Farrah Fulps July 2021