Article by Jack Bacheler
Adult kudzu bugs continue to flood into our soybean fields in southern NC. Thankfully, only low levels of nymphs are being produced as of the beginning of this past week. The high number of egg masses in some of these soybean fields suggests that nymphal levels could increase sharply during the coming week. In this past week’s soybean scouting schools, we could find low levels of kudzu bugs in both Northampton and Halifax counties, though this was mostly on kudzu with low levels of adult in some soybean fields. It would be fair to say that kudzu bug flights into soybean are ongoing and probably have not peaked yet. It will be very interesting to see if our more northern counties reach threshold levels this year. We may be benefiting from the fact that North Carolina soybean producers grow approximately 10-fold more soybean acreage than grower in Georgia, so we may be benefiting from some dilution up our way. Remember to base insecticide sprays on 15 nymphs per 15 sweeps taken away from field edges. Early instar fuzzy green nymphs are very small – along the lines of adult aphids as can be seed on Fig. 4. Treating for adult kudzu bugs without nymphs only invites additional kudzu bug applications and greater odds of subsequent corn earworm and other caterpillar establishment.
So far kudzu bug adults have been far more attracted to April and May planted soybean than to June to early July planted beans, especially behind wheat.