Army worm is one of Perth’s most destructive lawn pests — a heavy infestation can strip a lawn quickly. Birds feeding on the lawn at dusk are often the first sign.
The most reliable early indicator — birds are eating the larvae.
Brown or stripped areas appearing quickly
Fast-spreading damage, often after a hot spell.
Green frass on the soil surface
Small dark-green pellets between blades confirm active feeding.
Moths over the lawn at dusk
Small moths in the warmer months lay the eggs that hatch into larvae.
Caterpillars at the base of the grass
Easiest to find at night with a torch.
Perth-specific
Why It Happens in Perth
Perth’s warm, dry summers suit army-worm moth breeding, and lawns already stressed by water restrictions recover more slowly from damage. Kikuyu is the most vulnerable; buffalo varieties show more resistance but are not immune.
Perth treatment guide
How to Treat It
Read the label. Always follow current product label directions before applying any pesticide or chemical — rates and safety intervals vary by product. We apply all products per APVMA label requirements.
1
Confirm the infestation first
Check for larvae at the base of the blades (a torch helps at night). Don’t treat blind — several problems look similar.
2
Apply a suitable insecticide at dusk
Larvae feed near the surface at night. Always follow the current product label.
3
Water in lightly
A light water-in moves product into the thatch where larvae feed; avoid heavy irrigation that dilutes it.
4
Watch for a second hatch
Eggs keep hatching for about a week — a follow-up may be needed for heavy infestations.
5
Fertilise once control is confirmed
Feeding after the pest is gone speeds leaf regrowth — not before.
Not sure which product or how severe it is? The Lawn Clinic ($99) confirms it before you spend money on the wrong treatment.
Post-treatment recovery
Recovering Your Lawn
Most lawns recover within roughly 4–8 weeks once the infestation is controlled and the lawn is watered and fed. Heavily shaded or drought-stressed lawns take longer. If recovery stalls, a secondary problem (fungal or dry patch) is common.
Not sure it’s army worm perth?
Confirm it — book a Lawn Clinic
Several lawn problems look alike. Getting the diagnosis wrong means treating the wrong thing and wasting money on products that won’t work.
Through the warmer months, generally summer into autumn. Watch for moths and for birds feeding on the lawn at dusk as early warnings.
Rarely. Most lawns recover within about 4–8 weeks once treated and properly watered and fed.
Yes — suitable products are available, applied per the APVMA label. If you’re unsure of the pest or severity, a Lawn Clinic confirms it before you spend on the wrong treatment.
Couch mite causes tight, distorted growth at the runners rather than fast stripping. Army worm strips larger areas quickly, usually with bird activity at dusk.
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