Yellownecked Caterpillar (Datana ministra)
U.S. Department of Agriculture, Forest Service. 1979. A guide to common insects and diseases of forest trees in the northeastern United States. Northeast. Area State and Private Forestry, Forest Insect and Disease Management., Broomall, PA. p. 123, illus.(USDA Forest Service, Northeast Area State and Private Forestry Publication. NA-FR-4)
The yellownecked caterpillar is seldom a widespread forest pest, but heavily infested trees may be defoliated completely by mid- to late summer. Defoliation appears first on the periphery of the tree crown. The preferred hosts are white and yellow birch, basswood, elm, oak, maple, butternut, walnut, mountain-ash, eastern hophornbeam, and honey locust.
In June and July, females lay eggs in masses of 100 or more on the undersides of the host leaves. A newly hatched larvae has a black head and a reddish body with narrow, yellow stripes. Larvae feed in colonies on foliage at branch ends. When disturbed, larvae raise both ends of their bodies. Mature larvae are black with four narrow, yellow stripes running the length of the body. The neck is circled by a narrow, yellow band. Moderately dense, long, white hairs cover the body. When mature, larvae drop to the ground, where they pupate and overwinter in the soil. There is one generation per year.