This is Part 1 of a three-part series on summer diseases of turfgrass.
Fairy ring is a disease common to all turfgrass species in a wide range of environments and applications including home lawns, sports turf, and golf courses.
Researchers have identified over 60 fungi responsible for the disease. In general, the disease symptoms are visible as a ring and are classified in three distinct types:
- Type I – ring pattern with dead, hydrophobic turf on the perimeter, meaning the turf is repelling or failing to mix with water.
- Type II – dark green ring pattern of stimulated turf, sometimes with puff balls or mushrooms; no dead or hydrophobic turf.
- Type III – stimulated green ring pattern with mushrooms growing along the perimeter.
Type I fairy ring with the dead hydrophobic turf is the most troublesome and difficult to control, with the symptoms becoming more pronounced during warm weather. Fairy rings tend to occur in the same spots every year, so mapping the rings and applying a preventive treatment is typically done as soil and air temperatures rise above 60 F.
Best Management Practices for Fairy Ring Control
- Apply soil surfactants/wetting agents to avoid the development of hydrophobic soil conditions.
- Control thatch with vertical mowing, core aeration, and sand topdressing.
- Mask the visual ring symptoms with light rates of nitrogen and iron sulfate fertilizers.
- Make preventive fungicide applications on a spot treatment basis to areas of recurring fairy ring infestation as soil and air temperatures increase above 60 F.
- The amount of water carrier is key, generally 2 to 5 gallons/1000, to move the fungicide into the zone of fungus activity.
- For curative control, needle tine the affected area followed by applying a tank mix of surfactant and fungicide. Rinse into the turf to get the material into the zone of the fungus.
- There are several fungicides that are effective for fairy ring suppression and control. (See link below).
- Make plant growth regulator applications separately.
More information and details about specific fungicides for fairy ring control can be viewed at GreenCast Online.
Contact me if you have any questions about fairy ring disease or other turf-related topics. Also be sure to review Part 2 and Part 3 of this series to set your golf course up for success this summer:
• Detect Summer Turfgrass Diseases – Part 2 Anthracnose
• Detect Summer Turfgrass Diseases – Part 3 Gray Leaf Spot