Japanese Beetles (Popillia japonica)

What are Japanese beetles?

Japanese beetles (right) are important turf and landscape pests in the eastern US. The adults are roughly 3/8" long with coppery wing covers, metallic green back and a row of white tufts along the sides. Adults feed on a wide variety of plants where they "skeletonize" leaves (remove leaf tissue between the veins). Japanese beetles belong to a large family of ornate beetles called scarabs (Scarabidae). These beautiful beetles have even been used in religious ceremonies by a number of ancient cultures.

Japanese beetle larvae, or white grubs, are typical of other scarab larvae. Larvae live in the soil where they feed on plant roots and can do serious damage. Larvae are white with a brownish head capsule and three pairs of legs. The "tail" end is usually packed with ingested soil particles and larvae are generally bent into a characteristic "C" shape as well.

common misspelling: Japanese beatle

Use low toxicity insecticides and traps for adult beetles

EcoPCO WPX (right) is a botanical insecticide that can be safely used to treat landscape plants against Japanese beetle feeding. Neem oil insecticides are also effective feeding deterrents but must be re-applied every few days as long as beetles are present. And, Japanese beetle traps are very effective for adult control and as a way to determine if this pest is present when populations are low.

Use milky spore to control beetle larvae

Larvae can sometimes be controlled with a bacterial insecticide called "milky spore". Milky Spore is applied to the soil where, over time, the bacteria build up and eventually infect larvae. Milky spore is very safe and does not infect other organisms. Milky spore may take several years to become effective but should be a part of your arsenal if this pest is a problem in your landscape.

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Identification guides, reference and gardening books, etc.