Chafer Grubs (Garden Chafer & Cockchafer)
Soil-dwelling white grubs feeding on roots in turf and nursery stock.
Chafer grubs, including garden chafer (Phyllopertha horticola) and cockchafer (Melolontha melolontha), live in the soil and feed on roots of turf, nursery stock and ornamental plants. Symptoms include yellowing, thinning turf and areas that lift easily due to root loss. Birds and mammals may cause secondary damage while feeding. Biological control relies on Heterorhabditis species nematodes applied to moist soil when grubs are small and actively feeding.
Biological Controls for Chafer Grubs (Garden Chafer & Cockchafer)
The species below are examples of beneficial organisms commonly used against chafer grubs (garden chafer & cockchafer). Recommendations are based on published biological control information and practical IPM experience. Always confirm suitability for your crop, growing system and local conditions before use.
Heterorhabditis bacteriophora
Environment: outdoor
Temperature Range: 5.0 – 25.0°C
Rate: 0.5–1 billion nematodes/ha
Frequency: Repeat annually at peak grub stage
Effective against chafer larvae in turf and amenity; ensure good soil moisture and apply in dull weather.
Atheta coriaria
Environment: all
Temperature Range: 10.0 – 30.0°C
Rate: 10–50/m²
Frequency: introduce early; top up as needed
Support-only predator layer for soil pest complexes; primary control remains entomopathogenic nematodes.
Further BioWiki Reading
For more background on pest biology, beneficial insects and environmental factors, use the BioWiki alongside this practical control guide.
Related Biological Solutions
Growers dealing with chafer grubs (garden chafer & cockchafer) often also monitor these pests as part of a complete IPM programme: