There are yellow-green bugs eating the flowers on my roses. What are they and how can they be controlled?
The yellow-green bugs are probably the adults of the northern corn rootworm. The larvae of the northern corn rootworm feed on the roots of corn plants. The adults (yellow-green beetles) appear in mid-summer and are present until frost. Corn rootworm beetles feed on corn silks and tassels. When the tassels and silks dry up, the beetles migrate to nearby gardens and feed on the flowers of many annuals, perennials, and roses. They are especially fond of plants with yellow flowers.
Control of northern corn rootworm beetles in gardens is difficult. While insecticides, such as Sevin, are effective, northern corn rootworm beetles continue to migrate from corn fields to gardens until a hard frost. As a result, repeated insecticide applications are necessary. Another option is to protect plants with cheese-cloth or fine mesh netting.