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| Leaf casebearer |
(From USDA Forest Service General Technical Report NC-5)
The leaf casebearer, which is closely related to the walnut shoot moth, is a much less serious pest of black walnut. Both species are commonly found in the same plantation. Because they are nearly identical in appearance, they are best distinguished by their feeding habits. Larvae are drab, olive-green with a black head capsule. They grow to 3/4 inch long. Adults are gray-brown moths.
Damage: A small amount of defoliation may occur in a tree heavily infested with the pecan leaf casebearer. Normally, however, these insects cause little damage to expanding buds or to leaflets.
Biology: Newly hatched larvae overwinter in protective cases near the terminal bud. In early spring the larvae leave their cases and move to buds where they begin chewing on the outer surface of the bud scale. Feeding continues as the bud expands. A pile of excrement may conceal a feeding larva but the larva never bores inside the bud. As the larvae grow older and the leaf grows larger, the larvae move to about the middle of the leaf and construct a black trumpet- or cone-shaped case around themselves. From the case, which remains attached to the undersurface of the leaf stem, larvae feed on walnut leaflets.
Control: No control is recommended.