Host Selection and Acceptability of Selected Tree Species by Gypsy Moth Larvae, <I>Lymantria dispar</I> (L.)

Abstract

The larva of the gypsy moth, Lymantria dispar (L.) (Lepidoptera: Lymantriidae), is considered to be one of the most serious forest pests of North America. We investigated the feeding preferences of fifth-instar larvae to seven overstory tree species in eastern Maryland, including sweet gum, Liquidambar styraciflua (L.); sugar maple, Acer saccharum (Marsh.); tulip poplar, Liriodendron tulipifera (L.); American beech, Fagus grandifolia (Ehrh.); American basswood, Tilia americana (L.); red oak, Quercus rubra (L.); and black walnut, Juglans nigra (L.), using two-choice bioassays. Feeding of larvae was determined for all possible pairings of plant species. Tests showed that sweet gum and red oak were the most highly acceptable species. Sugar maple and basswood were secondarily favored, whereas beech and black walnut were least favored. Tulip poplar was generally strongly rejected. These findings indicate that fifth-instar gypsy moth larvae exhibit a clear hierarchical feeding preference.