Description:

Japanese beetle adults are approximately 3/8 inches in length. The front of the beetle is dark metallic green. Its wing covers are a metalic dark tan. The beetle has two small patches of short white hairs on its rear, and five white hair tufts along each side of the dorsal abdomen. These patches are key characteristics for identification. If it does not have these patches, but has the other color traits, then it may be the false Japanese beetle.

Life cycle:

The larval or grub stage of the Japanese beetle is a "C" shaped white grub that lives in the soil. Its primary food source is grass roots, but it is known to feed on the roots of corn, beans, tomatoes, and strawberries. All "white grub" species are similar looking but vary in their life cycles, and identifying the grub to species is important for the proper timing of pesticide application.

Pest Status:

The grub's primary food source are grass roots, but is known to feed on the roots of corn, beans, tomatoes, and strawberries.

Control:

Timing of pesticide treatment is important. Larger grubs are more difficult to control with insecticides, and the grubs are difficult to kill in the fall because they are larger. Preventative chemicals should be applied early, May through July, when eggs are first hatching and the grubs beginning to feed. Rescue treatments should be used in August and September. Treating grubs in the spring is also more difficult as they are bigger and do not feed for long before they pupate.

Please check the "Extension Agents' Handbook of Insects, Plant Disease and Weed Control".

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