Brown patch commonly starts as a small spot and can quickly spread outwards in a circular or horseshoe pattern up to a couple of feet wide. Often times while expanding outwards the inside of the circle will recover, leaving the brown areas resembling a smoke-ring.
Rings or patches of blighted turfgrass that measure 5 inches or more than 10 feet in diameter.
Leaf spots and "smoke rings" - thin, brown borders around the diseased patches that appear most frequently in the early morning.
Conditions Favoring Disease:
Active at cool temperatures on warm-season grasses in the spring and fall (over 85°F during the day and over 60°F at night).
Occurs in areas that experience extended periods of wetness.