Pest identification
What's eating my sweet chestnut?
Chestnut weevil (Curculio elephas)
Signs: Grubs tunnel through the entire nut interior; exit holes in fallen nuts and worm-riddled kernels indicate infestation; losses can reach 80% in warm years.
Control: Collect and destroy fallen nuts daily; hot-water dip (50°C for 45 minutes) sanitizes harvested nuts for storage; soil cultivations disrupt pupal stage.
Chestnut tortrix and related moths (Cydia splendana, Pammene fasciana)
Signs: Larvae feed inside nuts, often cohabiting with weevil larvae; infestation is only visible when nuts are opened.
Control: Pheromone traps for timing; spinosad or pyrethroid at adult flight peak; destroy fallen nuts promptly.
Squirrels and jays
Signs: Burrs are stripped or pried open at maturity; grey squirrels cause particularly heavy losses in UK woodland.
Control: Daily collection of windfall nuts; trunk baffles on isolated trees; accept some wildlife sharing as unavoidable.
Deer
Signs: Bark stripping, antler rubbing, and browse on low shoots on young trees during autumn and winter.
Control: Spiral tree guards and wire mesh cages on young trees; deer exclusion fencing on orchard plantings.
Keep sweet chestnut pest-free
Healthy plants resist pests best. Get the basics right:
Sweet Chestnut pests — FAQ
What is eating my sweet chestnut?
Sweet chestnut faces chestnut weevil as its most destructive nut pest across Europe and the UK, with moth caterpillars causing similar internal nut damage. Chestnut blight (Cryphonectria parasitica) threatens trunks in Continental Europe. Deer, squirrels, and jays compete aggressively for nuts. Prompt collection of fallen nuts is the single most effective control measure.
How do I get rid of chestnut weevil (curculio elephas) on sweet chestnut?
Grubs tunnel through the entire nut interior; exit holes in fallen nuts and worm-riddled kernels indicate infestation; losses can reach 80% in warm years. Collect and destroy fallen nuts daily; hot-water dip (50°C for 45 minutes) sanitizes harvested nuts for storage; soil cultivations disrupt pupal stage.
How do I get rid of chestnut tortrix and related moths (cydia splendana, pammene fasciana) on sweet chestnut?
Larvae feed inside nuts, often cohabiting with weevil larvae; infestation is only visible when nuts are opened. Pheromone traps for timing; spinosad or pyrethroid at adult flight peak; destroy fallen nuts promptly.
How do I get rid of squirrels and jays on sweet chestnut?
Burrs are stripped or pried open at maturity; grey squirrels cause particularly heavy losses in UK woodland. Daily collection of windfall nuts; trunk baffles on isolated trees; accept some wildlife sharing as unavoidable.
How do I get rid of deer on sweet chestnut?
Bark stripping, antler rubbing, and browse on low shoots on young trees during autumn and winter. Spiral tree guards and wire mesh cages on young trees; deer exclusion fencing on orchard plantings.