Corythucha spp.

Lace bugs in the genus Corythucha are pests primarily of deciduous host plants. At least 27 species of them feed on deciduous trees and shrubs. Luckily, the majority specialize on certain host plants, which helps when trying to identify these insects. Lace bugs are so named for the beautiful sculptured and lacy wings and thorax. All lace bugs in this genus overwinter as adults. They can be found on or near their host plants, in sheltered areas such as bark cracks and crevices or leaf litter below. C. pallipes or the birch lace bug overwinters in the leaf litter and other sheltered areas near its hosts (see list above). In the spring, adult females lay eggs in small groups on the lower surfaces of leaves and in the axils of leaf veins. The brown eggs are partially inserted into the leaf tissue. 5 nymphal (immature) instars occur over a period of 26 days before the birch lace bug matures to adulthood. These adults may be found in New England from mid-July through mid-September. Two generations of birch lace bugs can occur per year.

C. cydoniae or the hawthorn lace bug is found throughout much of the US and Canada and northern Mexico. Rosaceous host plants are favored (see above). One or more generations may occur per year, depending upon local climates. In New England states, there may be one generation per year, with development from egg to adulthood taking 5-7 weeks. In Maryland, at least 4 generations occur annually. 

The cherry lace bug (C. pruni) is primarily a northeastern species but may extend southward toward North Carolina. Prunus serotina is thought to be its only host. Adult cherry lace bugs overwinter in the leaf litter and grasses. Adults become active again in the spring at approximately the time cherry leaves are half-grown and flowers are in early bud. Females lay eggs by early May in Massachusetts. Brown eggs are laid in circular patches on the undersides of leaf blades, partially inserted into the leaf tissue. Egg hatch begins by early June and nymphs (immatures) take 4 weeks to develop. The time from egg to adulthood is approximately 7 weeks. In the northern parts of its range, there is a single generation per year of the cherry lace bug, with up to 4 generation per year in Maryland. The feeding of adult and nymphal cherry lace bugs results in a scorched appearance of cherry foliage. Feeding occurs on leaf undersides, but it most visible on the upper leaf surface. 

The sycamore lace bug (C. ciliata) is a common pest on sycamore. Adults overwinter beneath the exfoliated bark of its host and are active by the time leaves develop in the spring. Eggs are attached to the underside of host plant leaves with a brown, sticky substance, hidden within the leaf hairs. In approximately a few days, eggs hatch and nymphs (immatures) feed on the underside of sycamore leaves. Nymphs are spiny and black and look very different from the adults. It takes approximately 30 days to go from egg to adulthood. Two or more generations occur annually, but in Maryland there may be up to 5. By late summer, all life stages may be present on the leaf undersides of sycamore, including black, tar-like excrement. This species has also been collected from ash and hickory in the southern part of its range.