Integrated Approach in Controlling Japanese Beetles Project

Integrated Approach in Controlling Japanese Beetles Project

Summary

George tried three non-chemical means of controlling Japanese beetles in his blueberry bushes:
1) He applied Heterorhabditis bacteriophora, a nematode that is known to parasitize Japanese beetle grubs. This nematode harbors disease bacteria, which can kill infected grubs within a few days;
2) He applied a disease known as “milky spore;” and
3) While waiting for the beneficial organisms to become established, and produce their effect, he vacuumed the adult beetles for several hours each week from late July to late August, when they were most in evidence.

All treatments were applied during the summer of 1998, and again in 1999.
George reports that, unfortunately, his treatments had no discernible effect on the levels of Japanese beetles in his blueberry plantings. He suggests that too much rain right after application might have inhibited establishment of the milky spore, and conversely, too little after application of the nematodes might have kept them from being washed into the ground where the larvae hide. The vacuuming, while definitely more efficient than shaking the bushes and picking the beetles off the ground, as is sometimes done, was not cost-effective. Besides being very labor-intensive, vacuuming tends to frighten away as many, perhaps more, beetles than can be captured this way.