Dollar Spot Fungicides

Dollar spot is one of the most common and costly turf diseases. It affects many cool- and warm-season grasses and is especially damaging on low-mown golf turf.

What to Look For

Small bleached spots the size of a silver dollar appear on closely mown turf and larger straw-colored patches develop at lawn height. Individual leaves show hourglass-shaped tan lesions with reddish-brown margins; white cobweb-like growth may be visible in morning dew.

Why It Develops

Warm days, cool nights, heavy dew, low nitrogen, drought stress, and extended leaf wetness favor infection. The pathogen spreads through infected clippings and equipment rather than airborne spores.

Reduce Disease Pressure

• Remove dew by mowing, rolling, dragging, or targeted irrigation.
• Maintain adequate nitrogen without producing lush growth.
• Prevent drought stress and improve airflow.
• Clean equipment before moving from active areas to clean turf.

What University Research and Extension Guidance Says

Penn State's 2026 update highlights dew removal, lightweight rolling, balanced fertility, and tolerant cultivars as meaningful reductions in disease pressure. Resistance has developed to several single-site fungicide groups, so use local sensitivity information when available, rotate FRAC groups, and include effective multisite partners where permitted.

Choosing and Using a Fungicide

Use the products below as a starting point, then match the active ingredient, FRAC group, turf species, use site, timing, rate, interval, and watering directions to the current product label. Preventive or very early applications are usually more reliable than rescue treatments after extensive injury. Rotate effective FRAC groups and combine fungicides with the cultural changes above.

Research and label note: University research may identify useful activity even when a current product label does not name this disease. That is research evidence, not a label direction. Apply a product only where the turf or application site and use pattern are permitted, and follow the complete label and applicable state requirements.

University sources: Penn State Extension: Dollar Spot; Penn State Extension: SDHI Fungicides for Turfgrass Diseases.