Answer: I don't think all is lost, but you certainly have a fight on your hands! Both adult and immature Japanese beetles are highly destructive pests. Adults emerge in July and August and feed on the foliage and fruit of hundreds of species of plants, often skeletonizing the leaves and gouging the fruit. The beetles are 1/3 to 5/8 inch long with a metallic green body and bronze outer wings. They have several small tufts of white hairs along the sides of the abdomen and a prominent pair of tufts near the tip. Females intermittently stop feeding to lay eggs in buried 2 to 6 inches deep in soil.
The eggs hatch by midsummer. Larvae, which are among the many kinds of ?white grubs? found in lawns and pastures, feed in the roots of grasses and other plants. Japanese beetle grubs are the most widespread turf-grass pest in the United States. They pass the winter buried in soil and complete their development in late Spring.
The insecticide carbaryl (Sevin) is very effective against the adult beetles. However, repeated use of Sevin will cause mite populations to explode (which can cause other problems in your garden). Because of this, it is best to leave the adult beetles alone in most cases. Traps may be used to suppress Japanese beetles, but the traps must be placed at least 30 feet away from the plants to be protected. The traps will draw in adult beetles. If the trap is too close to the plant to be protected, the beetles may stop and feed for a while before entering the trap.
Milky spore disease is a bacterial disease that kills Japanese beetle grubs. Spores of this bacterium are produced commercially and sold under the names of Doom,, Japidemic, and Milky Spore. The application of milky spore may reduce the numbers of Japanese beetle grubs in lawns but beetles will fly in from other areas to damage plants and crops.
Hope this information provides some help!
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