Casemakers and skeletonizers—Bucculatrix spp.
Bucculatrix cocoons occur on host tree bark, leaves, and nearby plants and objects. Adults are
mottled white, brown, and black. First-instar larvae mine inside the leaf. Later instars feed externally
on the lower leaf surface. Damaged foliage between leaf veins appears translucent. Mature larvae are olive
green with rows of pale spots. There are two generations a year for each species, one each in the spring
and summer, except for the birch skeletonizer, which has one generation.
pupal and round larval cocoons
patches caused by casemaker larvae