Ground beetle
Carabus spp.
Role in the garden
A nocturnal generalist predator: slugs, snails, chafer grubs, eggs and caterpillars fallen to the ground. Predation of Colorado-beetle larvae stays marginal in Europe (documented mostly for Lebia grandis in North America). Garden species include the golden ground beetle (Carabus auratus) and the leather beetle (C. coriaceus).
Activity period
March to November (active at night)
How to attract / manage it
The “golden ground beetle”, a large metallic golden-green beetle, notably hunts slugs.
Practical guide
Where to find them
Under flat stones, boards on the ground, thick mulch, at the base of hedges. Active at night, hiding by day. Recognisable: long (1-3 cm), shiny (green, black, bronze, or copper), long legs for running, visible mandibles.
Prevention
Thick, permanent mulch in the vegetable garden. Multi-species hedges with natural soil at their base. Flat stones or tiles left on the ground as shelter. Work the soil as little as possible: tillage often reduces their populations (Kromp, 1999). No insecticide on the soil.
Sources
- Kromp, B. (1999). Carabid beetles in sustainable agriculture: a review on pest control efficacy, cultivation impacts and enhancement. Agriculture, Ecosystems & Environment, 74(1-3), 187-228.