Kudzu Bugs in Soybean Fields
Kudzu bugs have been spotted a few fields in Johnston County. For soybeans less than 1 foot tall, the threshold has 5 bugs (adults) per plant. For 1-2 feet tall soybeans, the threshold has 10 bugs (adults) per plant. I always check a random 100 plants away from field edge as one plant could have 20-30 adults. For soybeans near/at reproductive stages (flowering/pod set/pod fill), 1 nymph (baby) per sweep is the threshold. Take at least 15-20 sweeps per field. A sweep net should be used. During the sweep, contact the middle portion of the plant. When examining sweep net contents, nymphs tend to cluster in the bottom of the net. Scouting should continue until soybeans reach R7. We have been very fortunate over the past couple of years because a fungus, Beauveria bassiana, which attacks both adults and immatures has lowered populations in soybeans. The fungus has the appearance of a powdery white mold on the insect itself. However, due to extremely dry conditions, I have not yet seen the fungus. Please look for this white mold on the insect as you scout. I encourage all growers to check fields before doing a one-time insecticide application that may wipe out beneficials and increase numbers of other pests.
Control Recommendations from the NC Ag Chemical manual