Fruit trees are among the most preferred foods of Japanese beetles, so it is a perennial battle. Adult beetles are most active from mid July through August and can quickly ravage foliage and ripening fruit, when beetles are present in large numbers. They can feed upon more than 300 different species of plants, but are especially fond of roses, grapes, smartweed, soybeans, corn silks, flowers of all kinds, and flowering crab, plum and linden trees, as well as overripe and decaying fruit. There are a number of strategies that can be employed to help reduce the damage. Check out Purdue Extension Bulletin E-75 “Japanese Beetles in the Urban Landscape,” for more information.
Rosie Lerner is a consumer horticulture specialist with Purdue University.