Take-all patch is a fungal turf grass disease that infects the crowns and roots of the plant, causing it to die out in a slightly depressed circular pattern. In severe cases this disease can be devastating to turf as it can be a difficult disease to control.
This disease primarily attacks bent grass turf and is most active between mid summer (June) and late autumn/early winter. However, in severe cases it may persist.
It is very common on newly constructed sand based golf greens, especially when the root zone has been sterilised. Sterile root zones are devoid of any bacteria and micro organisms which are required to inhibit the pathogens that cause take-all patch disease.
Over time the micro organism populations increase and fight the disease reducing the severity. Eventually the disease goes into what is known as ‘take-all decline’ and dies out.
Take-all is often triggered by a sudden rise in the soil pH which can be caused by applying alkaline materials or even alkaline water used for irrigation.
Identifying Take-all patch
The initial symptoms begin with a slight reddening of infected bent grass turf usually in a ring pattern. As the disease progresses weeds and resistant grasses may invade the infected area of the turf. This invasion of weeds is often referred to as “the frog eye appearance”.
Initially the infected patches may measure only a few centimetres in diameter, however, they may increase to over a metre in diameter as the severity of the outbreak increases.
Conditions that favour Take-all patch
- A high percentage of bent grass in the sward.
- Newly constructed sand/USGA golf greens, which are relatively sterile and have had insufficient time to build up a healthy population of micro organisms.
- Root zones that are alkaline and especially where there has been a sudden rise in the pH.
- An excessive thatch layer.
- Poor surface drainage.
- A lack of adequate nutrition.
- Use of alkaline materials and irrigation water.
Preventing and curing Take-all patch
- Encourage a healthy sward with good lawn care practices and maintain good turf vigour by applying adequate nutrition.
- Ensure good surface drainage with regular aeration to remove surface water to encourage a dry turf surface.
- Avoid applying products and materials that are alkaline (high pH) or have a high lime content.
- Control thatch build up with scarification and aeration.
- Applying materials that acidify the lawn surface such as lawn sand, sulphate of ammonia and iron may help prevent an outbreak or reduce the severity of the disease if it is already present.
- A fungicide can be applied for the control of take-all patch, at present the only people allowed to apply fungicides are turf professionals and lawn specialists with the relevant pesticide application certificates. The most effective fungicide for the control of this disease is Heritage (azoxystrobin).
- Over seed with grass species that are resistant to take-all