Identification and Reproduction
- Adult European Chafer beetles are tan or brown beetles resembling June beetles but measure only about 1.5cm in length.
- The grubs, measuring 2 to 2.5 cm, are soft, white, and C-shaped with tan-coloured heads and six prominent legs
April to Late June
- Adult beetles emerge from the soil and fly to nearby deciduous trees to swarm, mate and feed. Once mated, females deposit eggs (up to 50 eggs per female) in the soil. During this time, beetles cause minimal damage to turf.
- Eggs hatch in July, and the larvae (grubs) begin to feed on turf grass roots. Infected turf may feel “spongy” when stepped on due to the grubs tunneling underneath. During this time, damages to turf can be seen by brown, dying patches of grass.
October - March
- The grubs grow as they continue to feed in fall and winter. They remain within 5cm of the ground surface unless in freezing conditions when they burrow deeper into the soil. During this time, damage to turf is most serious. Birds, skunks, and other predators dig up grasses to feed on the mature grubs. The grubs continue to feed until they pupate (undergo metamorphosis) to become adult beetles in May.
Habitat & Ecology
- They are a nuisance because the grubs feed on the roots of all kinds of different plants, including turf and grass, destroying the plants.
- Their life cycle is only one year long, which means that their population rapidly increases.
- European Chafer Beetle reproduces rapidly and feeds on the roots grass and turf used for lawns
- You may also see birds, skunks, and other predators digging up your lawn in search of grubs.
- Keep your turf healthy.
- Adopt a vigorous maintenance routine involving aerating, dethatching, fertilizing, deep watering, and mowing.
- In high traffic areas consider grass replacements such as mulch or paving stones, or use alternative ground covers.
- Check bylaw regulations in your area before using any pesticides.
- Nematodes (Heterorhabditis bacteriophora) can be used as a biologicail agent to manage chafer beetle. Check the following link for more detail. https://vancouver.ca/home-property-development/chafer-beetles.aspx
Photo: Todd Murray, WSU