Japanese Beetle

Japanese Beetle: (Size=1/2 inch)
Still primarily a pest of the eastern U.S., they turn up west of the Rockies from time to time. They're a problem for gardeners for their appetite for a wide variety of plants: Adults feed on just about every kind of flower or vegetable, sometimes in disturbingly large crowds. They chew out the leaf tissue between the veins, leaving a lacy skeleton. Prior to pupating, the white, 1-inch long, C-shaped grubs live in the soil and feed on the roots of most all plants. Grubs are often a problem in lawns.

Controls:
Play Defense: A multi-part attack is best. Start by spraying the affected plants with neem insecticide at the first sign of attack.

Neem oil comes from a tree; when sprayed on plants, it reduces feeding. Scientists call it an antifeedant. Important: neem works best when applications begin at first sign of attack.

Hand Pick: Japanese beetles are slow. You can easily pick them off plants with your hands and toss them into a bucket of soapy water. Do it in the morning when the beetles are sleepy.

Prevent: Although the following solutions won’t provide immediate gratification, you will be better off next year. Grub Guard kills the grubs that turn into Japanese beetles. Ideally, apply it in spring before the beetles emerge. The second half of this 1-2 prevention punch is Milky Spore, which also kills grubs. It takes a year or so to get established in your soil, but it keeps working for 10 years or more.

Repel: Select plants that beetles don't (usually) like, such as ageratum, arborvitae, ash, begonia, boxwood, caladium, cockscomb, dusty miller, hydrangea, juniper, pansy and yews.

Trap: The Catch-Can with Bait is recommended only if you have a large yard, and can place the trap away from your garden. If you have a small yard, you'll just be telling the beetles, "The party’s at my house!" If you use a trap, put it out for a day or two at a time every couple of weeks.

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