Some insects, like caterpillars that turn into beautiful butterflies and pollinate our flowers and feed on the plants in our landscapes are not that damaging but some of them, like Bag Worms, if allowed to go unchecked, can ruin a plant’s ornamental value or actually kill it. These harmful ‘worms’ destroy the foliage by eating it to the point that the plant is so weakened that it eventually dies or is very unsightly. The problem is that Mother Nature has made them so camouflaged that they are not even noticed until the plants look like this:

Bag Worms, not to be confused with Tent Caterpillars or the Fall Web Worms, which are annoying but do not cause any long lasting damage to trees, can be devastating to evergreens trees and shrubs. The Bag Worm’s “home”, pictured here, is many times mistaken for a pine cone on spruce or arborvitae. This “home” moves along with the young worm(see photo). The casing is so impervious that pesticides used to kill the insect will not penetrate it. The best way to eliminate this critter is to manually pick the casings off the plant and spray with something like Sevin when the insect is young and coming out of its casing to feed. The young insect moves about by swinging from plant to plant, on a silk like thread that blows in the wind. The adult matures in the “bag” and overwinters there until spring when the female emerges and lays eggs that hatch and repeats the process again until the plants are destroyed.

Meadow View Growers, www.meadowview.com