Bagworms in Hopkins County

Dr. Mario Villarino- County Extension Agent-CEA Agricultural and Natural resources

The small, silk weaving that resembles a Christmas tree ornament on your favorite tree or shrub is not decoration. These bags protect the caterpillars, or larvae, pupae, female adults and eggs of bagworms. Bagworms attack trees and shrubs including cedars, cypress, junipers, pines and spruce and broadleaved plants such as apple, basswood, black locust, boxelder, elm, honey locust, Indian hawthorn, maple, various oaks, persimmon, sumac, sycamore, wild cherry and willow. Although bagworms are not abundant every year, once a plant is infested the insect becomes a persistent problem unless controlled. Infestations, which may not be noticed at first, can defoliate trees and shrubs, and kill these plants if left unchecked.

Handpicking bagworms off the plants is the cheapest way to control them. Pick off all of the bags and destroy or discard them. Eggs in bags thrown on the ground will hatch in the spring and develop into larvae that could reinfest the plants. If handpicking isn’t practical or safe, use insecticide spray. Apply insecticide soon after bagworm eggs have hatched or while the larvae are small and feeding. Determine the right time for treatment by collecting bags in late winter and keeping them in a container out of sunlight. Once the caterpillars hatch from the bags in the container apply insecticide to plants. Chemical control is not as effective when the caterpillars close their bags to molt or pupate but can reduce numbers for the following generations. Use spray equipment that gives complete coverage of all foliage. Hire a professional exterminator if you do not have adequate equipment. If you need more information on this or other agricultural related topics please call the Hopkins county extension office at 903-885-3443.

_____