At this point, we have officially entered a new phase in the kudzu bug saga with at least two fields known to have very high numbers—one each in Isle of Wight and Culpeper Counties—and both need to be treated with insecticide. Most of the infestations seem to be confined to field edges or corners of fields. That being the case, we are recommending spot treatments—knowing that some fields are small enough that whole field treatment makes more sense.
In general on the statewide level, kudzu bugs have cycled through the overwintering adult stage, have laid egg masses, and nymphs have hatched—at least this appears to be the case in the fields we have visited. We think the few adults we are seeing are second generation adults that will set up another cycle of nymphs.
We are relying on thresholds ‘imported’ from the researchers in the south. I am most concerned about fields in the flowering or pod development stages and the threshold for those fields is an average of one nymph per sweep (15/15 sweeps). Again, we are now seeing a limited number of fields at or above threshold but I anticipate that 1) there are likely a lot more at threshold but not indentified since many fields are not being checked, and 2) many more fields are going to hit threshold before the season is completed.
We are trying to stay abreast of this situation and will keep updating our advisories.