Problem: Spring Dead Spot
Problem Info
Circular dead spots develop in bermudagrass lawns when growth begins in the spring. Spots vary from a few inches to several feet in diameter. The dead grass is sunken and straw colored, and the stolons and roots are blackened and decayed. Weeds may invade the affected areas. Bermudagrass sometimes slowly fills in by the end of summer, but is shorter than the surrounding healthy grass. Grass may grow back only in the center of the spot, creating a frog''s-eye pattern. In bermudagrass lawns overseeded with a cool-season grass, affected areas appear as light-green spots.
Analysis
This lawn disease is caused by three fungi (Leptosphaeria korrae, Ophiosphaerella herpotricha, and Gaeumannomyces graminis var. graminis) that affect bermudagrass, causing stolon and root rot. Spring dead spot is common in areas where temperatures drop low enough to promote winter dormancy of bermudagrass. It is most likely to develop in lawns with excess thatch and in lawns that are overfertilized or fertilized late in the growing season.
Solution Advice
Avoid overfertilization and late-season fertilization. Keep thatch to a thickness of no more than 3/4 inch. Keep the lawn healthy and vigorous to encourage bermudagrass regrowth into dead areas. Replace the sod and soil of badly diseased areas.
