Dollar Spot is Still Active
The dollar spot fungus (Clarireedia spp.) remains active and continues to infect both cool- and warm-season turfgrasses. The recent period of lower temperatures and extended leaf wetness has created favorable conditions for disease development and symptom expression. As a result, dollar spot activity is ongoing. Turfgrass managers should continue to monitor closely for disease outbreaks and implement timely management practices. Dollar spot is especially problematic on bermudagrass and zoysiagrass, where it appears as small, straw-colored spots that can coalesce into larger blighted areas under conducive conditions. It has been particularly severe in seashore paspalum this spring.
Management Strategies
An integrated management approach is recommended for effective dollar spot control:
- Maintain adequate nitrogen fertility, as low nitrogen levels favor disease development.
- Reduce prolonged leaf wetness by improving air circulation, avoiding late-afternoon or evening irrigation, and scheduling irrigation during early morning hours.
- Remove dew from turf surfaces through mowing, rolling, or dragging a hose to reduce infection periods.
- Avoid excessive thatch accumulation, which can create a favorable environment for the pathogen.
- Promote healthy turf growth through proper mowing, fertility, and irrigation practices.
- Application of fungicides when environmental conditions are favorable for disease development and symptoms are first detected. Fungicides containing active ingredients from different FRAC groups should be rotated to minimize the risk of fungicide resistance.
For more information on dollar spot identification and management, consult the latest recommendations from University of Georgia Extension turfgrass disease resources. https://fieldreport.caes.uga.edu/publications/C1091/dollar-spot-on-turfgrass-in-georgia/
https://turf.caes.uga.edu/publications/pest-control-recomendations.html
Inquiries About Fairy Ring, Mushrooms, and Puffballs Continue Following Recent Rain Events
Questions regarding fairy rings, mushrooms, and puffballs in turfgrass have become increasingly common following the recent periods of rainfall across Georgia.
Fairy ring is caused by more than 50 species of basidiomycete fungi, many of which produce mushrooms or puffballs after extended periods of wet weather. Symptoms typically appear as patches, rings, or arcs that gradually enlarge over time and, in severe cases, can cause significant turfgrass damage or death.
Fairy rings are classified into three types based on the symptoms they produce:
- Type I: Turfgrass is severely damaged or killed.
- Type II: Turfgrass growth is stimulated, resulting in dark green rings.
- Type III: Turfgrass growth is unaffected, and the only visible symptom is the presence of mushrooms or puffballs.
Type III symptoms are most commonly observed during prolonged wet periods when fungal fruiting bodies emerge. In contrast, Type I and Type II symptoms are more prevalent during the hot, dry conditions of summer, when the fungus can alter soil water relations and stress the turf.
The most effective approach to fairy ring management is preventing the fungi from becoming established in the turfgrass system. Because fairy ring fungi thrive on organic matter, cultural practices that reduce excessive organic material can help suppress disease development. Core aerification, thatch reduction, and improving soil conditions can reduce favorable environments for the pathogen. Turfgrass within affected rings should be irrigated and fertilized appropriately to encourage recovery and promote new growth.
Before establishing turfgrass, it is advisable to remove buried stumps, dead tree roots, and other woody debris that can serve as a food source for fairy ring fungi. In golf course settings and other intensively managed turf areas, fungicide applications may be used as part of an integrated management program while corrective cultural practices are implemented.
More information on fairy ring can be found at:
https://fieldreport.caes.uga.edu/publications/C1346/fairy-ring-in-turfgrass-identification-and-control-in-georgia/ https://turf.caes.uga.edu/publications/pest-control-recomendations.html
