2 Bugs That Look Like Japanese Beetles
Think you found Japanese beetles? These 2 bugs are the ones most often mistaken for them. Each entry below shows how to tell the difference.
How to recognize a real Japanese beetle
- Metallic green head and thorax with coppery wing covers
- Five tufts of white hair along each side of the abdomen
- Feeds in groups, leaving lace-like skeletonized leaves
1. June Bug
A heavy, reddish-brown beetle that crashes into screens and porch lights on late-spring nights. Its C-shaped white grubs live in soil and chew grass roots.
How it differs:
- Size: June Bugs are larger, reaching 25 mm, while Japanese beetles top out around 15 mm.
- Color: Japanese Beetles are green, metallic and brown; June bugs are brown.
- Where found: look for Japanese beetles in gardens and on plants and in lawns and grass; June bugs turn up in lawns and grass, in gardens and on plants and indoors.
2. Emerald Ash Borer
A slim, bullet-shaped, metallic green beetle whose larvae tunnel beneath ash tree bark. It has killed hundreds of millions of ash trees across North America.
How it differs:
- Color: Japanese Beetles are green, metallic and brown; emerald ash borers are green and metallic.
- Where found: look for Japanese beetles in gardens and on plants and in lawns and grass; emerald ash borers turn up on trees and shrubs.
- Signature feature: Japanese Beetles: metallic green head and thorax with coppery wing covers. Emerald Ash Borers: bright metallic emerald green body.
Side-by-side comparison
| Japanese Beetle | June Bug | Emerald Ash Borer | |
|---|---|---|---|
| Group | Beetles | Beetles | Beetles |
| Scientific name | Popillia japonica | Phyllophaga spp. | Agrilus planipennis |
| Size | 10–15 mm | 12–25 mm | 8–14 mm |
| Colors | Green, Metallic and Brown | Brown | Green and Metallic |
| Legs | 6 legs | 6 legs | 6 legs |
| Wings | Yes | Yes | Yes |
| Bites or stings | No | No | No |
| Risk | Nuisance | Nuisance | Nuisance |
| Key feature | Metallic green head and thorax with coppery wing covers | Chunky, shiny reddish-brown to dark brown body | Bright metallic emerald green body |
Quick identification checklist
- Count the legs. Japanese Beetles have 6 legs.
- Check for wings. Japanese Beetles have wings.
- Measure it. Japanese Beetles are 10–15 mm (up to about 0.59 in).
- Look for the signature feature: metallic green head and thorax with coppery wing covers.
- Note where you found it. Japanese Beetles are usually in gardens and on plants and in lawns and grass.
When you'll see Japanese beetles
Japanese Beetles are most active in summer. Summer heat speeds up development, so populations can grow quickly.
Typical places to check: garden or plants and lawn or grass.
About beetles
The Japanese beetle is one of the beetles. Beetles go through complete metamorphosis: egg, larva (grub), pupa and adult. The larval stage often does the most feeding and damage, and it can last from a few weeks to several years depending on the species. Adults protect their flight wings under hard wing covers called elytra, which is why most beetles look armored and meet in a neat line down the back.
Look closely at larvae as well as adults. Grubs in soil, fuzzy larvae in closets and small worms in flour are all beetle larvae, and finding them tells you where the problem is centered.
Are Japanese beetles or their lookalikes dangerous?
- Japanese Beetle: Japanese beetles do not bite or sting people; the harm is to plants and turf.
- June Bug: June bugs are harmless to people; they do not bite or sting.
- Emerald Ash Borer: Emerald ash borers are harmless to people but lethal to untreated ash trees.
Frequently asked questions
What bug looks like a Japanese beetle?
The closest lookalikes are June bug and emerald ash borer.
How can I be sure it's a Japanese beetle?
Look for these features: metallic green head and thorax with coppery wing covers, five tufts of white hair along each side of the abdomen and feeds in groups, leaving lace-like skeletonized leaves.
Are Japanese beetles dangerous?
Japanese beetles do not bite or sting people; the harm is to plants and turf.