Our surveys of roadside kudzu patches this summer have the invasive kudzu bug showing up in two more southern Maryland counties. Two kudzu patches off of route 5 were found to have adult kudzu bugs; one in St. Mary's County, and the other in Charles County. This brings the total to five Maryland counties confirmed to have kudzu bugs present. We also suspect that the kudzu bug has made it to some of the counties on Maryland's Eastern Shore, since the insect has been reported in the Delaware and Virginia portions of the Delmarva peninsula.
Of course the invasion of the kudzu bug into Maryland was expected to occur this year, as a part of the northward dispersal from it's introduced range in the south. The real question for kudzu bug in Maryland is how large of a population our climate can support. Currently the numbers of insects we are finding in kudzu patches is very low compared to the more sever infestations in the south. This may be because the insect is still becoming established, and numbers will increase for future summers, but we do not yet have the data to determine what those numbers might look like. Another factor is the amount of kudzu. Although the vine is present in Maryland, it's distribution is not nearly as widespread as it is in the south. However, more research will have to be done to see if the insect can develop on other closely related plant species that occur in Maryland.
As news of this new invasive insect reaches farmers, there will be growing concern about what this will mean for their crops. In the south, the insect completes an entire second generation on soybean plants, which can cause major crop loss if left untreated. However, for Maryland, we don't know if we will get a huge second generation because of the difference in climate. So far this summer we have focused on sampling kudzu vines since that is the primary host, and our primary goal was simply to detect the insect. For the rest of the summer we will also be scouting soybean fields to see if the insect moves into field crops, and at what numbers. So the potential is there for this insect to be a pest of economic concern in the future, but more research is definitely needed to figure out how bad it might be.