Sting Nematode on Turfgrass
The sting or southern sting nematode is a tiny worm that even when fully grown, is only about 3 mm long. Like all nematodes, it has a tubular body without any segments. The sting nematode infests turfgrass grown for bowling greens, golf courses and lawns.
Turfgrasses with high nematode populations can lose their visual appeal and be a costly problem for clubs, as users of bowling greens and golf courses seek high quality playing surfaces. This fact sheet explains how to identify suspected sting nematode damage, preventative management options and where to send samples for identification.
The most obvious signs of sting nematode infestation are irregular, discolored and thinning patches on turfgrass that do not respond to fungicides, irrigation, fertilization or aeration and become overrun by weeds (Figure 1) (1, 3). Below ground signs are short stubby roots (Figure 2) and a reduction in the fine feeder roots (2).
Figure 1. Discoloured and thinning patch in turfgrass caused by the sting nematode (Image courtesy of Ken Johnston).
Figure 2. Roots of turfgrass "pruned" by the sting nematode (Image courtesy of Ken Johnston).
Environment and spread
Sting nematodes live in the soil. They feed by inserting their stylet into roots, injecting enzymes and then sucking out plant nutrients. Sting nematodes prefer soils with a high sand content, especially well irrigated soil. Nematodes can spread in soil on plant material, machinery and clothing or boots (1).
Sting nematode is present in New South Wales, Western Australia (4), Queensland, South Australia and Victoria (5).
A full host range remains undefined, but includes bent grass
(Agrotis stolonifera and Agrotis tenuis
(5)), couch grass (Cynodon dactylon),
kikuyu grass (Pennisetum clandestinum),
- Establish turf on sites that are free of the nematode.
- If the site is infested, consider chemical treatment options to reduce nematode populations.
- Plant turfgrasses from suppliers known to be free of sting nematode.
- Reduce stress on turfs by slightly raising the mowing height.
- Fertilise well to counter poor nutrient uptake from roots damaged by the nematode.
- Avoid excessive nitrogen fertilisation as it promotes root tip growth, providing a source of food for nematodes.
- Encourage deep root growth with deep, infrequent watering as a deep root system is more tolerant to nematode damage.
- Avoid compaction and promote aeration, which encourages a healthy root system and may boost tolerance to nematodes.
- Applying organic soil amendments may enhance turf growth and reduce nematode damage.
- Avoid shading turfgrasses as this reduces nutrient production and storage, which lowers the turf's tolerance to nematode damage.
- When managing turf, work on healthy sites first to avoid transferring nematodes from infested sites to healthy sites.
- Consider soil solarisation if practical.
- The Australian Plant and Veterinary Medicine Authority (APVMA) has a nematicide registered for sting nematode (7).
As damaged turf can be associated with a range of problems (including nematodes), obtaining a professional diagnosis from a reputable laboratory can save you valuable time, effort and pesticide treatments.
Reporting and further informatation
Please report any unusual pests and diseases of turfgrass to the Exotic Plant Pest Hotline on 1800 084 881 (toll-free) or email email@example.com photographs and a contact phone number.
For further information phone 136 186 for your local Plant Biosecurity Officer or email. firstname.lastname@example.org.
To arrange for nematode testing, phone Crop Health Services on (03) 9032 7515.