Q: I just discovered a really bad infestation of kudzu bugs on the beans in our garden. I looked into using spinosad and unfortunately we cannot use it because of our honeybees. From what I have read, it is highly toxic to the bees. The beetles seem particularly heavy on the beans that are putting up runners and getting ready to flower.
A: Kudzu bugs are definitely a menace to garden beans. One gardener says he has seen more damage to pole beans than to bush beans but I have no other confirmation of that.
Since you have honeybees, you’ll have to be careful which insecticide to use. Despite your doubts, I think you could use spinosad (Captain Jack’s Dead Bug Brew, Conserve, etc) if you spray directly on the bugs in the evening when your bees are in the hive. Spinosad is a contact poison and does not stay active on leaf surfaces for long.
One source says “…… once residues have dried completely, toxicity to foraging bees is considered negligible. ”
You could also make traps for the bugs by coating empty milk jugs with Tangle-Trap Brush On Sticky Trap Coating. This won’t control a bad infestation but if you deploy the traps next April you’ll catch many of the parents of kudzu bugs that would otherwise appear in June.
One gardener caught an assassin bug attacking a kudzu bug!