Full-grown greenstriped mapleworm caterpillars are 1.5 to 2 inches long with pale green bodies and red heads. Running the length of the body are alternating light and dark green lines. On the second thoracic segment is a prominent pair of black, slender horns. Small black spines are found on the tops and sides of each abdominal segment (spines are found only on sides on young caterpillars), and larger spines and a red side patch are found on the terminal segments of the abdomen. Common host plants include maples, and oaks that are growing in mixture with maple. Populations of this caterpillar may reach levels that can cause serious defoliation.

About the family

Royal moths and silkworm moths of the Saturniidae family include many of the largest and most colorful moths in North America and the world. These large caterpillar species are usually not considered pests. Although a single individual can consume relatively large amounts of foliage, their numbers rarely reach levels that would warrant control. But there are a few species that can do significant damage to many forest tree species. Upon completing their larval development, most saturniid caterpillars will pupate in large, tough silken cocoons usually attached to twigs or leaves or found on the ground. Many species have only one generation per year.

IPM1019, new February 2003