Brown Patch – sometimes referred to as Large Patch or Rhizoctonia Blight – is a hot weather turfgrass disease. Brown Patch affects most turfgrasses throughout the United States, with damage signs appearing during late summer in the northern states and during fall through mid winter in the southern states.
Identifying Brown Patch -
Brown Patch typically produces rings or patches of browned out turfgrass that can measure from 5 inches to 10 feet in diameter. It may also produce thin, brown to purple borders around the margins of the patches. These areas are commonly referred to as “smoke rings.”
After the grass leaves die, new leaves can emerge from the surviving crowns. On wide bladed species of turfgrass, leaf lesions develop with tan centers and dark brown to black margins.
Symptoms of Brown Patch can vary depending on the species, weather conditions and intensity of turfgrass management.
Conditions for Brown Patch Infection -
Brown Patch can only lead to an infection in your lawn if all of the following conditions are present:
1. Pathogen – Brown Patch (Rhizoctonia solani)
2. Host – All species of warm and cool season turfgrass
3. Environment – Hot, humid climates with temperatures in excess of 85 degrees Fahrenheit in the daytime, 60 degrees nighttime
Cultural disease control practices create favorable conditions for a healthy lawn, and often create unfavorable conditions for the growth of Brown Patch. Environmental conditions cannot be changed, but cultural practices performed by the homeowner can be modified to lessen the chance of extensive damage from Brown Patch. Scotts LawnService can help determine a plan for preventing and controlling Brown Patch in your lawn.
For Brown Patch control and treatment, Scotts recommends the following cultural control tips: