Lawn armyworm
Spodoptera mauritiaCaterpillars that feed at night and strip grass leaves down to the crown. Damage can spread across a lawn in days, then the lawn usually recovers once they're gone.
Identify
Is it lawn grubs? Identifying lawn pests
Brown patches aren't always pests. These are the signs to look for, and the checks that confirm it before you reach for a product.
Signs to look for
- Patches that look grazed or mown very short, spreading quickly over days
- Ragged, chewed leaf edges; in heavy feeding only the midrib is left
- Striped caterpillars up to about 40 mm long, most active late in the day and at night
- Moths around lights in the evening
Lawn grubs (curl grubs)
Heteronychus arator and other scarab larvaeC-shaped, cream-coloured beetle larvae that live in the soil and eat grass roots. Damaged patches turn brown and lift easily because the roots are gone.
Signs to look for
- Brown or dead patches that keep spreading, even with watering
- Turf that lifts easily at the edge of a patch, because the roots have been eaten
- C-shaped, cream grubs with brown heads in the top few centimetres of soil
- Birds digging and pecking at the lawn more than usual