Pluck 'em! My 91-year-old mother fondly remembers the summers of the late 1920s and '30s, when she and her siblings would catch Japanese beetles by the jarful. Back then Philadelphia had large infestations of them. We still have Japanese beetle problems, but not nearly as bad as when they were first spotted in the U.S. on iris bulbs in a nursery near Riverton in 1916. At that time, populations were very high in our area because we were close to the source, there were no known predators, and it's likely the beetles had been here for some time before they were discovered. Today, birds and skunks eat the grubs, which hatch from larvae and turn into adult beetles that plague our lawns in late fall and early spring by eating the roots of the grass and causing large bare spots. They also eat field crops and ornamental plants. Milky spore, a naturally occurring bacterium in concentrated powder form, can be used to control grubs. Apply when the ground is warm; only one treatment is necessary. I did this 10 years ago and have never needed to do it again. The few grubs I get are eaten by birds. Adult beetle activity usually peaks in July and August. Feeding beetles are best controlled by picking them off whatever they're eating and putting them in a jar filled with soapy water. If there are too many to hand pick, natural products such as neem or pyrethrins can be applied. Recent research has shown that beetle traps with pheromones inside work best when located several hundred feet from the garden — not in it, as the lure seems to attract ever more beetles who bypass the trap and head straight to the garden to eat. They can ravage a vast array of plants, including roses and sassafras trees. One of their natural predators is the anchor bug, closely related to the stink bug. Who would have guessed?