Dogwood sawfly is one of our most attractive defoliators
Editor’s note: This article is from the archives of the MSU Crop Advisory Team Alerts. Check the label of any pesticide referenced to ensure your use is included.
If you notice some of the leaves have been recently chewed on a dogwood tree, look closer for a powdery white, or a black, green and yellow caterpillar-like worm. It is the dogwood sawfly, a member of the Hymenoptera (bees, ants and wasps) that looks like a caterpillar. The young larvae are covered with a white powder, but after the final molt the larvae are a striking yellow and black like in the provided photo. You can tell the difference between caterpillars and sawflies by the number of fleshy legs on the abdomen. Caterpillars have five or fewer pairs of short, fleshy prolegs, while sawflies have on pair on each abdominal segment (10 pairs of pro-legs). Although the dogwood sawfly may sometimes eat most of the leaves on a dogwood tree, the damage is not important in September. This is an insect you can enjoy.
Dr. Smitley's work is funded in part by MSU's AgBioResearch.