- Affects mostly blue rye; less common in tall fescue.
- Most common during July thru September (higher humidity and warmer weather)
- Main cause — Keeping the leaf surface continuously wet (daily watering).
- Symptoms — Silver dollar size brown patches that occur in other wise healthy lawns. Patches can run together forming larger patches that loose their circular shape. Grass dies back from the tip and fine white threads of fungus can be found on the patches in the early morning hours when the leaf surface is wet.
Cultural Practices — to minimize chances of disease
- Low levels of fertility promote Dollar Spot; however, avoid applying high rates of Nitrogen, particularly in late spring and summer
- Water during early AM hours to allow grass leaves all day to dry off
- Avoid frequent irrigation that keeps the leaf blades wet and that results in water-logged/compacted soils
- Mow at the upper end of recommended mowing heights (but not above recommended mowing heights)
- Avoid wet compacted soils
- Spray on a fungicide labeled for Dollar Spot if symptoms appear… repeat every 10 days until symptoms are gone...ALWAYS READ & FOLLOW LABELED DIRECTIONS!