Japanese Beetle on Brambles
Return to Insects and Other Arthropod Pests
Japanese beetle (Popillia japonica) adults are 3/8-inch long metallic green beetles with copper-brown wing covers. Five small white tufts of hairs project from underneath wing covers at the tip of the abdomen. Mature larvae, which feed on roots of grasses, are crescentshaped grubs about 1 inch long with a brown head and grayish-black end. Hairs on the last body segment (raster) form a V-shape pattern near the anal opening. Beetles act primarily as defoliators, but may also feed on fruit as it begins to color. Feeding on leaf tissue between large veins results in skeletonized leaves near tips of canes.
Japanese beetle adults.
(Photo: Ric Bessin, University of Kentucky)
Japanese beetle larva (grub).
(Photo: Ric Bessin, University of Kentucky)
Management:
- Regularly monitor for Japanese beetle activity from mid-June through August.
- Control of grubs is ineffective in managing adult numbers.
- Do not use Japanese beetle traps near brambles.
- Manage adults with insecticides.
