Groups of these caterpillars are found within "tents" of leaves tied together and lined with silk. Full-grown caterpillars, about 1.5 inches long, are mottled brown-black with four distinct longitudinal yellow lines on top of the body, and a bright yellow longitudinal line on each side of the body. On top of the first and eighth abdominal segments is a black tubercle. The body is also sparsely covered with light hairs. Preferred host plants are poplar and willow.

About the family

Prominents and oakworms belong to the Notodontidae family. Caterpillars have variable color patterns and body texture. Some species are smooth with fleshy humps or projections while others are hairy. Some are cryptically colored, mimicking the edge of a partially eaten, distorted leaf, while others are brightly colored and conspicuous. In some species, when the caterpillars are disturbed, they raise both ends of the body, holding onto the substrate with the four mid-abdominal prolegs and exposing glands that produce irritating acidic chemicals to ward off potential attackers. Caterpillars exhibit both solitary and gregarious behavior. Host plants include a wide variety of trees and shrubs.

IPM1019, new February 2003