Squash and pumpkins are the most susceptible to squash bug attack. Symptoms and Diagnosis Squash bugs destroy plant tissue by sucking out the sap from leaves and stems and depleting nutrients from the plant. This feeding causes leaves to wilt and dry out. They eventually turn black and fall off the vine. Adult pests can be seen feeding on main stems.
Nymphs are more likely to be found feeding on the undersides of leaves.
In the spring when plants begin to develop runners, elliptical, yellow or brown eggs are laid in groups on the undersides of the leaves. Adults overwinter in garden debris and emerge the following spring. There is only one generation per year. Integrated Pest Management Strategies 1. Handpick bugs and eggs and destroy them by dipping them in a bucket of soapy water.