Brown patch occurs on close mown turf where patches of water soaked grass develop. The patches become tan to dark brown (Plate 1 above). In humid conditions a brown/grey 'smoke ring' may develop around the edge of the patch. On higher cut grass a light brown patch forms. Individual leaves may have lesions that are tan in the centre and bordered with a brown edge (Plate 4 above).
Where is Brown Patch found?
Brown Patch is not very common but it is most frequently seen on close mown areas such as golf greens and bowling greens. On longer grass lesions may be found by close inspection but it is rare to encounter patches of disease
When is Brown Patch likely to attack turf?
During the summer months, when the temperatures and humidity levels are high.
Effects of Brown Patch
Brown Patch reduces the aesthetic appearance of the turf. In severe cases grass cover may be lost in the patches.
High Risk Situations
- Temperatures over 20ºC
- Leaf wetness or high humidity
- Poor surface drainage
- Excessive fertility
- ITM Solutions
Integrated Turf Management
- Ensure the turf surface remains dry (switch the surface to remove dew), improving airflow over the area and irrigating infrequently and deeply will help to prevent outbreaks.
- Excessive levels of thatch can increase surface moisture. Therefore, the breakdown and removal of thatch should be encouraged by aeration.
- Excessive nitrogen fertiliser should not be applied as lush grass is more easily infected by R. solani.
- Regularly check GreenCast to identify periods of high risk
Banner Maxx has a label recommendation for leaf spot control in the UK.
- Systemic Mode of action
- Optimum timing at first sign of disease
- Dose rate 3.0 l/ha
- Water volume 400 to 1000 l/ha
Once conditions conducive to Brown Patch occur a preventative application of Banner Maxx should be applied.