Dollar Spot is Rife

Dollar spot is a fungal pathogen that thrives in warm (60-85 degrees F) and wet conditions. With relative humidity being in the 90th percentile recently, the disease has become prolific, particularly on nutrient starved turf. Symptoms appear first as small yellow spots on individual leaves but quickly expand to a straw-colored band with dark brown margins. The band extends across the leaf width and produces the classic "hour-glass" lesion. The entire grass blade will then bleach out and the turf will die, leaving light tan colored dead spots 2-3 inches wide, across the turf. On low cut turf, like golf greens, the spots are about 1-2 inches in diameter, or the size of a silver dollar, hence the name dollar spot.

BEST MANAGEMENT PRACTICES:

* Avoid nitrogen deficiency

* Avoid prolonged leaf wetness - do not water early evening or at any time that several hours of leaf wetness will follow

* Remove morning dew by dragging, irrigating or brushing

* Provide adequate soil moisture to promote growth

* Select turfgrass species & cultivars with better resistence to the fungal pathogen

* Chemical control can be successful at the onset of disease development. Once the disease is rampant it gets more difficult. For specific chemical recommendations see the resource section below.

* If turf has been killed, re-seed bare spots with more resistant species/cultivars and promote recovery with adequate irrigation and fertilizer.

RESOURCES:

Factsheet: Dollar Spot on Turfgrass (PDF)

Bulletin - Management of Turfgrass Diseases (PDF)

Dollar Spot Podcast by Dr. Karl Danneberger

OSU's Turfgrass Pathology program website