Just as last week, bean leaf beetles, green cloverworm, and Japanese beetles continue to be active. Low numbers of stink bugs can be found in reproductive stage soybean. As we move into August, be on the lookout for corn earworm, especially in open-canopied, stressed beans at R2 or beyond. Although we have not seen it yet, I feel that it is only a matter of time. August is also when we typically start picking up soybean looper and fall armyworm.
Other arthropods that are active right now include Dectes stem borer and spider mites. We also picked up a couple of soybean aphids during the last part of July. This insect is usually not a problem in Delaware, thresholds in other states are 250 per plant, sampled on 25 – 30 plants per field.
Start being on the lookout for sugarcane aphid. Last year this aphid caused significant damage to Virginia sorghum. It is as far north as Kentucky and southern Virginia.