Lawn & Turf Care Guide

ID: Adults are shiny black beetles 12–15 mm long with a broad shovel-like head. Larvae are creamy-white C-shaped curl grubs with brown heads, up to 25–30 mm.

Damage: Larvae feed on grass roots causing brown patches that lift easily like a carpet. Adults chew stems at soil level. Birds digging in lawn indicates grubs.

Season: Adults active Oct–Mar. Eggs laid Nov–Jan. Larvae peak damage Feb–May.

Control: Preventative: Acelepryn (chlorantraniliprole) applied Nov–Dec gives 6 months protection. Curative: bifenthrin (Rumbler), beta-cyfluthrin (Baythroid Advanced), fipronil.

ID: Adults are tan-brown beetles similar in size to African Black Beetle but lighter with faint wing-cover stripes. Larvae are white curl grubs, slightly smaller.

Damage: Larvae feed on roots, causing spongy turf and brown patches. Can reach 350+ larvae per m² in severe infestations.

Season: Adults active Nov–Feb. Larvae feeding Dec–May.

Control: Acelepryn (chlorantraniliprole) for prevention. Bifenthrin for active infestations. Same approach as African Black Beetle.

ID: Caterpillars up to 40 mm, dark green/brown with pale stripes along the body. Feed at night, hide in thatch during the day. Moths are grey-brown.

Damage: Chew grass blades, often creating large areas of closely-cropped or bare turf almost overnight. Feed in "armies" moving across the lawn.

Season: Most active late summer/autumn (Feb–May) in warm, humid conditions.

Control: Fast-acting: bifenthrin (Rumbler, Battle), beta-cyfluthrin (Baythroid Advanced). Preventative: Acelepryn. Apply late afternoon for best caterpillar contact. Water in lightly.

ID: Small cream/brown caterpillars (20–25 mm) that live in silk-lined tunnels in the thatch layer. Adults are small fawn moths that fly up when you walk across the lawn at dusk.

Damage: Chew grass blades at the base, leaving small irregular brown patches. Green frass (droppings) visible in thatch.

Season: Spring through autumn, multiple generations.

Control: Bifenthrin, Acelepryn. Water the lawn first to bring larvae to the surface, then apply insecticide late afternoon.

ID: Snouted weevils 10–13 mm long, dark brown/black. Larvae are creamy-white legless grubs with orange heads found inside grass stems and crowns.

Damage: Larvae bore into stems and crowns, causing yellowing and thinning. Turf pulls up easily. Sawdust-like frass at the base of stems.

Season: Adults active spring. Larvae damage peaks summer/autumn.

Control: Acelepryn (preventative, very effective), bifenthrin. Keep lawn healthy and well-fertilised to outgrow mild damage.

ID: Microscopic eriophyid mites — invisible to the naked eye. Diagnosis is by symptoms only: "witches broom" rosette growth at nodes, shortened internodes, tufted distorted growth.

Damage: Causes stunted, tufted "witches broom" growth in couch grass. Affected areas appear clumpy and fail to form smooth turf.

Season: Year-round, worst in warm conditions.

Control: Abamectin (Agador), or mite growth regulators (Finesse — hexythiazox). No fast knockdown — ongoing treatment needed. Remove heavily affected turf and replace.

ID: Large (30–50 mm) cylindrical insects with powerful shovel-like front legs for burrowing. Velvety brown body. Active at night — creates raised tunnels visible on the surface.

Damage: Tunnelling uproots grass and severs roots. Some species also feed on roots. Raised soil mounds and tunnels visible. Worst on sandy soils.

Season: Active spring/summer.

Control: Bifenthrin (apply evening, water in). Fipronil granules. Acelepryn for long-term control. Apply when surface is moist and mole crickets are near the surface.

ID: Dark grey/brown caterpillars up to 45 mm that curl into a C-shape when disturbed. Feed at night, hide in burrows during the day.

Damage: Cut grass stems at ground level, creating circular bare patches (especially in newly laid turf). Burrows with green frass at entrance.

Season: Spring through autumn.

Control: Bifenthrin, beta-cyfluthrin, Acelepryn. Apply late afternoon. Keep thatch levels down to reduce harbourage.

ID: Caterpillars up to 35 mm with a distinctive inverted Y-shaped marking on the head. Body colour varies from green to brown/black with three pale dorsal stripes. Larger larvae have dark spots with short spines. Moths are grey-brown with mottled forewings.

Damage: Aggressive leaf feeder — can devastate a lawn within days. Chews through grass blades from the edges, creating ragged transparent "window pane" damage. Feeds both day and night unlike native armyworm.

Season: Year-round in tropical/subtropical regions. Active spring through autumn in temperate areas. Classified as endemic in Australia since detection in 2020 — now present in all states except SA and Tas.

Control: Same products as native armyworm: Acelepryn (preventative), bifenthrin (Rumbler, Battle), beta-cyfluthrin (Baythroid Advanced) for active infestations. Apply late afternoon. Early detection is critical — check for frass and chewed leaf edges regularly.

ID: Various species build mounds in lawns, undermining root zones and creating uneven surfaces. Funnel ants (Aphaenogaster) are worst in sandy soils.

Damage: Mound building creates bumpy surface and smothers grass. Excavations undermine root zones.

Control: Bifenthrin granules or liquid applied to mounds and watered in. Fipronil-based baits. For funnel ants: liquid bifenthrin poured into nest holes.

Affects: All grass types, especially tall fescue, ryegrass, couch, buffalo.

ID: Circular brown/tan patches 15 cm to 1 m+ diameter. Dark "smoke ring" border visible in early morning dew on actively spreading patches. Leaves pull easily from the sheath.

Conditions: Warm humid weather (day temps 25–35°C), night temps above 20°C, prolonged leaf wetness.

Control: Azoxystrobin (Heritage), propiconazole (Bumper), trifloxystrobin + tebuconazole (Edict Duo), iprodione (Voltar). Reduce evening watering, improve air circulation.

Affects: Couch, zoysia, buffalo, bentgrass, ryegrass.

ID: Small (20–50 mm) bleached straw-coloured spots, often with hourglass-shaped lesions on individual leaves. White cottony mycelium visible in morning dew.

Conditions: Moderate temps (15–30°C), heavy dew, low nitrogen fertility, dry soil with wet leaves.

Control: Propiconazole (Bumper 625 EC), iprodione (Voltar), chlorothalonil (Chlortan 720), tebuconazole (Dedicate Forte). Increase nitrogen fertiliser — low N is a major contributor.

Affects: Kikuyu (especially), couch, buffalo, fescue, ryegrass.

ID: Small brown to purple spots on leaf blades that enlarge into oval lesions. In kikuyu: pinhead-sized brown/purple spots. In couch: white or black blotching. Severe cases cause "melting out" where whole plants collapse.

Conditions: Warm (20–30°C), wet/humid weather. Worst with excessive nitrogen and low mowing height.

Control: Chlorothalonil (Chlortan), propiconazole, azoxystrobin (Heritage), iprodione. Raise mowing height, reduce nitrogen in warm wet weather, improve drainage.

Affects: Perennial ryegrass, St. Augustine/buffalo grass.

ID: Small olive-green spots that rapidly enlarge to tan/grey oval lesions with dark brown borders. Twisted, scorched-looking leaves. Can cause rapid thinning.

Conditions: Hot (28–35°C), humid, prolonged leaf wetness. Worst with excess nitrogen.

Control: Azoxystrobin (Heritage), trifloxystrobin (Flint), chlorothalonil. Reduce nitrogen, avoid evening irrigation.

Affects: Couch grass (bermudagrass) — primarily in southern, cooler regions.

ID: Circular dead patches (10–50 cm) that appear in spring as couch breaks dormancy. Dead areas are bleached and sunken. Roots are blackened and rotted. Patches reappear in the same location each year.

Conditions: Cold winter temperatures, wet soils, high pH (alkaline). Disease infects roots in autumn but symptoms show in spring.

Control: Preventative fungicides applied in autumn: propiconazole, tebuconazole, fenarimol. Aeration and improving drainage helps. Acidifying fertilisers (ammonium sulphate) can reduce severity.

Affects: All grass types, especially ryegrass, fescue in warm/wet conditions.

ID: Greasy, dark, water-soaked patches that collapse rapidly. White cottony mycelium visible early morning. Grass feels slimy. Can kill turf in 24–48 hours in severe cases.

Conditions: Hot (above 30°C), humid, waterlogged. Poor drainage, over-irrigation, compacted soil.

Control: Phosphorous acid (Phosphoguard), metalaxyl (Subdue), propamocarb. Improve drainage, reduce irrigation frequency, avoid mowing when wet.

Affects: Ryegrass, fescue, bentgrass (cool-season grasses mainly).

ID: Small water-soaked spots (2–5 cm) that enlarge to 20 cm, changing from tan to brown to light grey. Orange-brown margins. White/pink mycelium in humid conditions.

Conditions: Cool to cold (0–16°C), wet, overcast conditions. Excessive nitrogen in late autumn.

Control: Iprodione (Voltar), propiconazole, fludioxonil (Medallion). Reduce autumn nitrogen, improve air movement, avoid late afternoon watering.

Affects: Ryegrass, zoysia, couch, buffalo.

ID: Orange/yellow/brown dusty pustules on leaf blades and stems. Rubs off on fingers, shoes, and clothing. Affected grass looks yellowish-orange from a distance.

Conditions: Moderate temps (15–25°C), high humidity, low light, low nitrogen, drought stress.

Control: Propiconazole, azoxystrobin, trifloxystrobin. Increase nitrogen and watering to promote vigorous growth — healthy turf outgrows mild rust infections.