The most common hosts of the eastern tent caterpillar in Bucks and Montgomery County include cherry, plum, crabapple, hawthorn, pear and birch. When searching for signs of this pest look for stripped foliage in late spring and early summer, as well as silky nests or tents located in the crotch of branches. Mature caterpillars are usually black with a white stripe down the back. Eggs hatch in the early spring, after which they begin building their protective tents. The larvae will feed for 6-8 weeks before migrating to a protected site to pupate. After 2-3 weeks the adult moths emerge. The females will deposit their egg masses around small twigs where they overwinter. Feeding from Eastern tent caterpillar larvae in late spring and early summer can completely defoliate foliage from trees. Healthy trees can tolerate a single defoliation event, however, multiple defoliation events can cause dieback when combined with abiotic stress events.
Easily reachable nests should be pruned out of the host after formation. Early morning or late in the day is best as most of the caterpillars will be in the tent. Foliar pesticide applications as well as soil or trunk injected systemic treatments are effective ways of controlling the eastern tent caterpillar. The size and bloom time of the host, time of year, and proximity to water are all factors which should be considered when choosing an appropriate treatment.
Contact Plant Health Solutions for proper diagnosis and to develop a treatment plan.