Japanese Beetles

Also known as: Popillia japonica

Identification

Metallic green and copper-colored beetle, 10mm long. Skeletonized leaves (veins remain). White C-shaped grubs in soil. Adults aggregate — pheromones attract more beetles.

Damage

Chewing — adults skeletonize leaves; grubs feed on grass roots

Best Organic Solutions (Ranked)

Solutions ranked by reliability tier — start with Tier A options.

Neem Oil Tier A

Antifeedant + IGR — reduces damage and reproduction

Pyrethrin Tier A

Fast knockdown of adults on contact

Milky Spore (Paenibacillus popilliae) Tier B

Long-term grub control (2-4 year establishment)

Kaolin Clay (Surround) Tier B

Barrier deters adult feeding

Beneficial Nematodes Tier A

Heterorhabditis for grub control

Biological Controls

Tachinid flies (Istocheta aldrichi), spring Tiphia wasps, parasitize grubs. Birds (starlings, grackles) eat exposed grubs.

Prevention

Do NOT use Japanese beetle traps — they attract 5-10x more beetles than they catch. Hand-pick into soapy water in morning when sluggish. Milky spore for long-term grub suppression.

Common Mistake

Using pheromone traps — research consistently shows traps attract far more beetles to your yard than they capture.