A couple of weeks ago I found this squash bug adult (Anasa tristis, Coreidae) overwintering inside a rotting tree. It was hanging out with a number of different spiders (note the webs), waiting for mild temperatures so it could resume its normal activity.
As the name suggests, the normal activity of squash bugs is feeding on squash. Although they prefer squash and pumpkins, these insects can attack any plant in the melon family (Cucurbitaceae). They’re pretty serious pests of these crops, and can damage plants by eating leaves and fruit, secreting toxic saliva, and vectoring disease. I used to find these frequently on pumpkins at my parents’ farm, and they caused notable damage to leaves and fruit.
Insecticides are of limited use against squash bugs since they tend to hide under leaves. There are, however, several parasitoid wasps and flies that help control their populations. These insects lay their eggs on the backs of squash bugs where the bugs can’t reach them. The eggs hatch and the parasitoid larvae burrow into the bugs, eating them from the inside out.