Damage symptoms
The garden chafer (Phyllopertha horticola) does most of its damage in the larval stage when it feeds on the roots. First instar larvae mainly feed on small humus particles, second instar larvae on fine roots of grasses. Third instar larvae can also feed on bigger roots. After the roots have been destroyed the larvae move into corms, rhizomes and stem bases of plants.
Larvae can also feed above ground within stems of plants and on strawberry fruits lying on the ground. Both adult beetles and larvae are polyphagous and feed on a wide variety of plant species. High populations of larvae can destroy plants under field conditions. Established crops are more resistant to damage than young plants or recently planted cuttings. The beetles are only active at night, taking round bites out of the leaves, starting from the edge. This damage is usually not a problem in vegetables and fruit crops but reduces the value of ornamental plants.
