Daily Progress, Jacksonville, TX

June 26, 2013

Baleful Bagworms: Insects infesting Cherokee County trees

Amy Brocato Pearson
Jacksonville Daily Progress

CHEROKEE COUNTY — If it's not beetles, it's bagworms.

Now that the mating period for harpalus beetles has pretty much ended, there's another insect ready to menace the area.

"Bagworms are showing up as a problem right now in Cherokee County." said Cherokee County Texas A&M AgriLife Extension Agent Kim Benton.

The bagworm (scientific name Thyridopteryx ephemeraeformis) attacks  trees and shrubs including evergreens such as arborvitae, 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. It's prevalent in East and Central Texas and is in peak season right now, Benton said.

You'll see the small, silky "bags" attached to trees and limbs.  The bags contain thousands of larvae ready to hatch. Adult females stay in "worm" form, while adult males morph into black and white moths.

Once a tree is infested, it's very hard to get rid of the bagworms, Benton said.

"If it's a first infestation, you can hand pick them off and destroy them," she said. "If it's a third or fourth season infestation, you should spray for them."

The bagworms, after hatching, infiltrate the tree and destroy all the foliage. They prefer conifers, but can be found in almost any evergreen.

"Conifers don't re-foliate easily," Benton said. "It'll look like the tree has been torched. They suffer significant damage from these pests."

Treat bagworms with almost any insecticide, she advised, including those containing carbaryl (such as Sevin brand) or malathion or natural insecticide "bt," or Bacillus thuringiensis.

"Be observant in your home landscapes. Try to rid your trees of them early," Benton said. "They're really hard to get rid of once they infest your trees."