GreenCast Tech Notes
Dr Ruth Mann
STRI
Volume 1, Issue 1 - June 2007
Time to think about dollar spot control
Spring arrived early this year, although April showers have been a month late. The temperatures are beginning to rise and it is coming to that time of year when dollar spot symptoms may become apparent.
Click here for GreenCast details of dollar spot
There have already been outbreaks in the South of England, although over the past few years the end May/beginning of June generally seemed to be when most Course Managers began to see the symptoms appear. Proactive management is the key to success for dollar spot control.
"Start control of dollar spotpreventatively, and continue through periods of conducive weather." Ruth Mann
Dollar spot is most common where the fertility is low. Keeping the fertility low is also important to encourage the finer grass species, such as fescue, which can be particularly susceptible to dollar spot. The use of liquid feed can help to reduce the potential dollar spot infection but allow you the control to keep the nitrogen input as low as possible.
Dollar spot typically breaks out in late May or early June, continuing right through to autumn | 
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Leaf wetness is particularly important for dollar spot infection. Keeping the turf surface dry will help to reduce the potential for infection. If it is necessary to irrigate, it should be done as close to dawn as possible so that the surface can be switched first thing to remove surface moisture.
Registered GreenCast members click here for the current dollar spot forecast
Low cutting height, compaction and excessive thatch can also encourage dollar spot. Therefore, raising the cutting height during conducive conditions, alleviating compaction and reducing the thatch layer through aeration may all help to reduce the severity of dollar spot.
BANNER MAXX and DACONIL TURF are two of the fungicides active against dollar spot. Control is best started preventatively and continued throughout periods of weather conducive to the disease. The mode of action of active ingredients should be rotated to prevent resistance occurring.
Remain vigilant for periods of dollar spot risk throughout the growing season; if the right weather conditions prevail, an outbreak controlled in June may still return with a vengeance in September!