The eastern tent caterpillar is a pest native to North America and is usually found in the eastern part of the U.S. It is commonly found on wild cherry, apple, and crabapple. It can also be found on maple, cherry, peach, hawthorn, pear, and plum, ash, birch, black gum, willow, poplar and oak.

Figure 1: Eastern Tent Caterpillar web. Steven Katovich, Bugwood.org

Identification

The larvae are hairy with a black and white stripe down the back, with brown and yellow lines on the sides, and a horizontal row of oval blue spots on the sides. Mature caterpillars are 2 to 2.5 inches in length. The adult moth is reddish-brown with two diagonal white stripes across each forewing.

Figure 2: Eastern Tent Caterpillars on web. William M. Ciesla, Forest Health Management International, Bugwood.org

Biology

The caterpillar overwinters as an egg mass covered with black a varnish-like material. The caterpillars hatch early in March about 13—160 (59 peak) GDD50. Cornus mas may be in full bloom when the eggs are hatching; thus this is a good time to scout. Caterpillars spin a tightly woven silk “tent” in the crotches of tree branches. The caterpillars reside inside the tent (nest) and emerge during the morning and evening to feed. The larvae feed on the foliage, and increase the size of the web. Mature caterpillars wander away from the “tent” after four to six weeks to search out a location to spin a cocoon, typically in the soil. Adult moths emerge from the cocoon in 3 weeks. Moths mate and begin to lay eggs on small branches which remain there until they hatch during the next spring. Populations found on host trees can be sufficient to cause defoliation.

Management Strategies

Parasitoids may parasitize the egg masses. Natural fungal viruses also infect the caterpillars and reduce population numbers. Removal and destruction of egg masses during the winter can reduce pest populations next spring. Small or large tents found early in the spring can be removed or torn open to allow natural enemies access to the caterpillars. Tents may also be pruned out of trees if able to do so and still maintain the appearance of the tree. Applications of insecticides are rarely warranted. If insecticide recommendations are desired, contact a local cooperative extension office for additional information.

References

Bessin, R. (2004). Eastern Tent Caterpillar. University of Kentucky College of Agriculture.

Davidson, J.A., Raupp, M.J. (2009). Managing Insects and Mites on Woody Plants: an IPM Approach. Tree Care Industry Association.

Hoover, G.A. (2011). Woody Ornamental Insect, Mite, and Disease Management.

Pennsylvania State University College of Agricultural Sciences.

Images: Bugwood.org

Download/Print PDF Version

UD Cooperative Extension

This institution is an equal opportunity provider.

In accordance with Federal law and U.S. Department of Agriculture policy, Cooperative Extension is prohibited from discriminating on the basis of race, color, national origin, sex, age, or disability.