Forest Health Protection, Southern Region

Importance. - The linden looper and eastern oak looper cause defoliation in the spring. Host species attacked include the red and white oak groups, maples, elms, hickories, ash, and cherry. Heavy defoliation usually occurs in May and June and can cause growth loss and mast reduction. If coupled with other stresses, this defoliation may cause mortality. The greatest impact of these insects is often felt in public use areas where defoliation reduces the aesthetic value, and larvae and their droppings create a nuisance.

Identifying the Insect. - Male moth wings are light gray to tan, with wavy lines, and a span of I to 1 1/2 inches (25 to 37 mm). Linden looper females are wingless, and the eastern oak looper female has wing pads, but cannot fly.

Mature larvae of these loopers are about 1 1/2 inches (37 mm) long. The eastern oak looper has a tan head and body, with many lengthwise, black, wavy lines. The larval segments have small, hairy tubercles. The linden looper has a rusty brown head, a tan back with numerous wavy black lines, and yellow sides. Coloring of both loopers varies with population densities.

Identifying the Injury. - Early evidences of feeding are small holes in the leaf produced by young larvae feeding on the expanding foliage. Older larvae consume the entire leaf, except the midribs and major veins.

Biology. - Adults emerge and lay their eggs in early spring. Eggs hatch at about the time of bud break, and the young larvae begin feeding on the expanding foliage. Feeding continues for approximately 6 weeks, then the mature larvae enter the soil and pupate.

Control. -The eggs and larvae are attacked by insect parasites and predators. Other natural enemies also help in control. Sticky bands placed around the trunks of high value trees can trap the females as they climb the tree to lay eggs. In high use or high value areas, chemical control may be needed.