Fine silky threads spun by the mites become particularly evident when populations are high. Management Biological Control. A tachnid fly that parasitizes adult beetles aids in controlling the bean leaf beetle in some states, however, little is known about natural enemies of the bean leaf beetle in Michigan. Beneficial insects and diseases usually regulate green cloverworm populations in most soybean growing areas. Japanese beetle populations are also kept in check by birds that feed on the beetles, and skunks and moles that eat the grubs.
Grasshoppers frequently succumb to disease organisms as well as a variety of predators.
Practices that promote healthy, vigorous soybean plants are effective in reducing the impact of all soybean defoliators. Soybeans grown under good conditions are remarkably tolerant of defoliation damage. Full coverage is not required when using systemic insecticides. Complete coverage is necessary for maximum efficiency when non-systemic insecticides are used. Drop nozzles may be needed for complete coverage if the canopy is large.