Australian turf managers regularly face insect and mite pressure that can weaken playing surfaces, reduce turf density and produce patchy symptoms resembling drought or nutritional stress.
Argentine stem weevil, couch mite and ground pearl damage different parts of the turf plant. Argentine stem weevil larvae feed within stems and crowns, couch mites feed beneath couchgrass leaf sheaths and ground pearls attack the root system below the soil surface.
Effective management depends on confirming the pest, identifying its life stage and selecting a treatment program based on monitoring and current product label directions.
Turf Pest Identification Guide
| Pest | Commonly affected turf | Typical symptoms | Important treatment stage |
|---|---|---|---|
| Argentine stem weevil | Bentgrass, wintergrass and ryegrass | Yellowing, thinning and irregular straw-coloured patches | Adults, eggs or young larvae, depending on the registered product |
| Couch mite | Couchgrass | Yellow leaf tips, shortened internodes, stunting and tufted growth | Eggs, nymphs and adults, depending on the selected miticide |
| Ground pearl | Susceptible turf growing in infested soil | Slowly expanding yellow or brown patches with poor recovery | Adults or crawlers |
Argentine Stem Weevil
Argentine stem weevil (Listronotus bonariensis) is particularly damaging in cool-season turf including bentgrass, wintergrass (Poa annua) and ryegrass.
Adults generally emerge from overwintering sites during spring and lay eggs beneath the leaf sheaths. After hatching, larvae feed inside the turf stems before moving into the crown, thatch and upper root zone.
The larvae cause the greatest turf damage. Their feeding kills individual tillers and can produce irregular yellow or straw-coloured patches that are easily mistaken for drought stress. Multiple and overlapping generations can occur between spring and autumn, making early monitoring important.
How to Monitor Argentine Stem Weevil
Adult activity can be assessed using an appropriate soap or pyrethrum flush. Turf managers can check for larvae by dissecting affected tillers or extracting larvae from turf plugs using salt flotation.
Monitoring should concentrate on areas where adult movement or turf stress is more likely, including:
- •Green surrounds and collars
- •Walk-on and walk-off areas
- •Dry slopes
- •High-traffic areas
- •Locations with a history of Argentine stem weevil
Symptoms may not become visible until larvae have already caused considerable internal damage. Monitoring should therefore begin before widespread yellowing or thinning develops.
Argentine Stem Weevil Control Options
Chemical treatments should be selected according to the pest’s current life stage and the turf situation included on the registered product label.
ProForce Curatol 120 SC
Curatol contains spinosad and is a Group 5 insecticide registered at 4 L/ha for the control of Argentine stem weevil in bentgrass.
The label recommends application when peak adult numbers are observed, when larvae are first detected in clippings or when the first visual symptoms appear. Applications should be made in 400–800 L of water per hectare to provide coverage of the leaves and penetration into the turf crowns.
Curatol works through contact and ingestion. Exposed insects stop feeding quickly but may take up to three days to die. The label permits up to three applications per season.
See all Argentine stem weevil solutions on the GTS Problem Solver
Couch Mite
Couch mite (Aceria cynodoniensis) is a microscopic eriophyid mite that primarily attacks couchgrass (Cynodon species).
The mites live and feed beneath the leaf sheaths, making them difficult to detect without magnification. Feeding can cause:
- •Yellow leaf tips
- •Shortened internodes
- •Stunted growth
- •Turf thinning
- •Tufted or witches’-broom growth
Couch mite populations can increase rapidly under favourable conditions because of their short life cycle.
How to Monitor Couch Mite
Inspect affected growing points and beneath the leaf sheaths using a hand lens or field microscope. Compare symptomatic plants with healthy turf from outside the affected area.
Monitoring should start when distorted growth first appears. Waiting until large sections of turf have thinned may make recovery more difficult.
Couch Mite Control Options
Successful couch mite management requires appropriate product selection and thorough spray coverage. Different miticides target different stages of the mite life cycle, so treatment programs should not rely repeatedly on one active ingredient or mode-of-action group.
ProForce Malice Duo
Malice Duo contains abamectin and clofentezine, Groups 6 and 10A. It is registered at 1.35 L/ha in 400–800 L of water per hectare for couch mite in turf.
The product is positioned as an early curative treatment after the first symptoms become apparent. Its two active ingredients provide activity across multiple stages of the mite life cycle.
Ground Pearl
Ground pearl is a soil-dwelling scale insect that feeds on turf roots. During part of its life cycle, the pest is protected inside a hard, pearl-like cyst within the soil.
Affected turf may develop slowly expanding yellow or brown patches. These areas often recover poorly from irrigation, nutrition or general turf maintenance because root feeding has reduced the plant’s ability to take up water and nutrients.
Established infestations can be particularly difficult to manage because the protected cyst stage is challenging to reach with chemical treatments.
How to Monitor Ground Pearl
Take soil cores or spade samples from the boundary between healthy and affected turf. Inspect the roots and surrounding soil for hard, round cysts.
Sampling at the edge of the affected patch is generally more useful than sampling turf that has already died or severely declined.
Ground pearl can be moved between sites in contaminated soil, turf and equipment. Good site hygiene is therefore an important part of management.
Ground Pearl Control Options
ProForce Scarlet Trio
Scarlet Trio contains clothianidin, clofentezine and abamectin, Groups 4A, 10A and 6. It is registered for ground pearl in turf.
Applications should target adults or crawlers when detected, generally from early spring through to the end of summer. The label requires application in 400–800 L of water per hectare.
The registered product rate, irrigation requirements, repeat-application instructions and site restrictions should be confirmed from the current label before use.
Established cysts are protected within the soil and are difficult to control. Treatment programs should focus on the vulnerable stages identified through monitoring rather than applying products after widespread turf decline is visible.
Integrated Turf Management
Chemical treatments are only one component of a turf pest management program. Turf that has adequate roots and balanced growth is generally better able to tolerate feeding damage and recover after pest activity is reduced.
Helpful cultural practices include:
-
01
Maintaining consistent soil moisture without overwatering -
02
Using balanced nutrition -
03
Maintaining an appropriate mowing height -
04
Avoiding scalping -
05
Managing thatch where necessary -
06
Reducing unnecessary movement of infested soil or turf -
07
Cleaning soil and plant material from equipment before moving between sites -
08
Keeping monitoring and treatment records
Avoid excessive nitrogen applications that produce soft growth without supporting root development.
Where a small ground pearl infestation is confirmed, obtain technical advice before removing soil or returfing. Careless movement of infested material could spread the pest to another part of the site.
Frequently Asked Questions
How can couch mite damage be identified?
Look for shortened internodes, yellow leaf tips, stunted growth and tufted growing points in couchgrass. Confirm the pest by inspecting beneath the leaf sheaths using suitable magnification.
When should Argentine stem weevil monitoring begin?
Monitoring should begin before expected spring adult activity, particularly in areas with a history of infestation. Local conditions and turf type will influence the exact timing.
Why is ground pearl difficult to control?
The feeding stage can be protected inside hard cysts within the soil. Management programs therefore focus on detecting and targeting more vulnerable adults or crawlers.
Should turf insecticides be irrigated after application?
It depends on the product and target pest. Some treatments need to remain on foliage or around the crown while others require movement into the soil. Always follow the wash-in or irrigation instructions on the current registered product label.
Getting the Timing Right
Argentine stem weevil, couch mite and ground pearl have different biology and treatment requirements, making correct pest identification and treatment timing essential.
The most reliable management programs combine regular monitoring, accurate pest identification, treatments directed at vulnerable life stages and resistance-aware product selection.
For help confirming a pest or developing a program for your turf situation, contact a Greenway Turf Solutions technical field agent.
Always read and follow the current registered product label. Product registrations, rates and directions may change. The information in this article is general in nature and does not replace label directions or site-specific technical advice.
