Brown Ring Patch/Waitea Patch

It appears that there is now a second occurrence of Brown Ring Patch / Waitea Patch (Waitea circinata var circinata) on Poa annua in Ohio. The first was during the “hot” period of March when temperatures suddenly approached 80°F / 27°C. Cases were confirmed in NW and Central Ohio. Now there are samples and cases in SW, Northern and Central Ohio. If temperatures cool down and then there is a sudden warm / hot period symptoms may occur again!

The disease is often active during the transition period of winter/spring to hot early summer like weather conditions experienced this year. Even though the disease may be widespread on greens and surrounds and tees, and the symptoms can be very noticeable, in most cases serious damage does not occur. When there is prolonged infection of the Poa annua plants there can develop on the leading edge (outer portion of the ring) of the affected patches a narrow band of brown leaf tissue. If this disease is a concern or if there is a history, fungicide applications may be considered. Products in the DMI/ Sterol Inhibitor family, some Strobilurins and flutolanil, have been used successfully. Also polyoxin D and fludioxonil have been used but may require more frequent applications. If an application(s) is made, keep in mind the importance of developing a well-planned and thought-through turf health management program and how additional fungicide applications fit the goals of overall disease management and turf health.

The following link is an excellent power point presentation with additional information about the disease and its management: Brown Ring Patch by Dr. Frank Wong & Chi-Min Chen, UCR,  and Dr. Larry Stowell, PACE.

Author: Joe Rimelspach, Program Specialist  - Turfgrass Pathology.