Eastern Tent Caterpillar
In the early spring, homeowners often notice white silken tents in the branch crotches of cherry, crab apple, and apple trees. These webs are made by the Eastern Tent Caterpillar. This caterpillar has long brown hairs, a white stripe on the back which is bordered by yellow-brown and black lines, and blue and black spots on the sides. These caterpillars can also, but less frequently, be found on ash, birch, blackgum, willow, witch-hazel, maple, oaks, poplar, peach, and plum trees, although cherry trees are the preferred hosts. There is only one generation (egg-caterpillar-pupa-adult) per year.
Each summer the adult female moth will lay 100-300 eggs in a dark brown varnish-like egg mass around a small twig in June or July. The caterpillars do not hatch from the eggs until the following spring, typically in March-April when the cherry buds are breaking. After hatching, the caterpillars collectively make the tent and begin feeding on the newly emerging leaves. Caterpillars will leave the protective nest to feed on the leaves. After several weeks to a month, the fully grown caterpillars will leave the nest for a final time to find a protected place to make their cocoons (pupate). In the early summer, the light brown adult moths emerge (usually May-July) from the cocoons. After mating occurs, the female will lay eggs and the cycle will begin again.
Control is usually not necessary as there is little to no damage to the trees; the defoliated trees will refoliate. If the homeowner finds the webs offensive or annoying, the tent can be destroyed with a stick.