Some minor defoliators have been noted in soybean this growing season, including caterpillars, beetles, and grasshoppers. Specifically, soybean defoliators observed include green cloverworm, soybean looper, alfalfa caterpillar, imported longhorn weevil, Japanese beetle, and Iowa colaspis beetle. It is important to remember that soybean can tolerate as much as 40% defoliation during vegetative growth stages, and 20% during pod-forming and pod-fillings stages before yield loss occurs. If defoliation is observed during scouting, it is important to identify the insect or combination of insects.
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