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
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
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!