Jeffrey Hahn, Asst. Extension Entomologist
People have been finding stag beetles in their yards and gardens recently, sometimes in large numbers. Also known as pinching bugs, these beetles typically measure a little more than one inch in size and are reddish brown to dark brown in color. Stag beetles resemble June beetles but have more prominent heads. The mandibles (jaws) of both sexes are also large and conspicuous, especially those of males. Stag beetles have short antennae with conspicuous asymmetrical plates (lobes) at the end of them which they are not able to close together. One of the most common species in Minnesota is Lucanus placidus.
All stag beetle larvae feed in dead or decaying wood, such as logs and stumps. Most adults emerge in May or June and feed on sap that exudes from plants. Stag beetles are active at night and are often attracted to lights. They can fly into a yard, land on the ground and remain there until the following morning. Some people have observed stag beetles emerging from the ground. This indicates that there are some old roots or other buried decaying wood where the larvae were feeding and developing.
Although a lot of stag beetles in a yard is annoying, they are harmless to people and property. Do not spray stag beetles, their control isn't necessary. Just ignore them until they go away on their own.