Blister beetles are out now, but rarely reach damaging numbers in alfalfa. In addition, the beetles feed on clover, soybean, potato, tomato, and eggplant, and are especially attracted to flowers. Like the Japanese beetle, feeding by a few blister beetles draws in more. Large numbers of beetles can cluster on small patches of flowering plants in an otherwise uninfested field. This can result in infested hay. Blister beetles contain cantharadin, a chemical that is very toxic to horses. Fortunately, these insects have not been a significant problem in Kentucky alfalfa fields.