Answer: Japanese beetles are a difficult pest to control. Your best bet is a two-prong approach: one to deal with the larvae, one to deal with the adults. Japanese beetle larvae are the white, C-shaped grubs you find in the soil. They are best controlled by spraying beneficial nematodes on the lawn and garden area. The microscopic worm-like nematodes harm only the grubs in the soil and not plants, animals or humans. Spray them in spring when the temperatures are above 55F and you should see a difference this summer. For adult beetles, try handpicking combined with a neem oil spray. Avoid using Japanese beetle traps. In some cases, it appears that they actually draw beetles to them from the surrounding area -- and you don't need to be attracting extra beetles!
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