Blister Beetle Management in Forages and Field Crops(E1002, revised December 2021)
Blister beetles (Coleoptera: Meloidae) get their name from the cantharidin toxin in their body fluids, which can cause blisters on people’s skin if handled and life-threatening inflammations in horses and livestock. Blister beetles are occasional pests of field crops including alfalfa, sweet clover, canola, dry beans, faba beans, soybeans, potatoes and sugarbeets. They also are injurious to a wide variety of vegetables and many flowers (Figure 2) and other ornamentals. Blister beetles are gregarious and are often found in high numbers in localized areas of the field. Blister beetles are not normally major insect pests and only cause occasional crop damage when conditions are favorable. However, when they occur in alfalfa and other forage crops where they may be ingested by horses or other livestock, serious illness or even death may result.