Blister beetle

Chewing pests

Blister beetle adults are 19 mm long and elongated. They vary in color from black and blue to brown, with or without stripes. They possess a characteristic constricted neck. These beetles overwinter as larvae in the soil. Adults feed on flowers and leaves, creating small rounded or irregularly shaped holes.

blister beetles blister beetles color variant
Adult beetles with stripes (left), and color variations include black like these adult beetles (right).


Adults can be hand-picked, but it is important to wear gloves because these insects release a caustic substance when crushed that can cause blisters and welts on the skin. Contact insecticides may be used to control the adults.

blister beetle damage

Print a PDF of this page: Blister beetle

Back to IPM scouting in herbaceous perennials.

The MSU IPM Program maintains this site as an access point to pest management information at MSU. The IPM Program is administered within the Department of Entomology, fueled by research from the AgBioResearch, delivered to citizens through MSU Extension, and proud to be a part of Project GREEEN.