Turf affected: All warm-season turfgrasses, especially St. Augustinegrass and zoysiagrass.
Symptoms: Circular brown areas up to 20 feet in diameter that can develop during cool, wet weather in spring or fall. Leaves will wilt and die, resulting in large brownish tan areas.
Disease occurrence: November through May
Management: Avoid excess nitrogen during potential disease development periods. Avoid readily available forms of nitrogen, such as soluble liquids or quick-release nitrogen sources, just prior to or during these periods. Instead, use slow-release nitrogen sources like Milorganite. Water deeply but infrequently early in the day to allow the leaf blade to dry off. Collect and dispose of grass clippings when disease is present.