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Brown Patch Disease in Southern Lawns

Are you Noticing Brown Patches in Your Lawn?

In mid to late spring, some homeowners start to notice unusual patterns and spots in their lawn. Brown patch (also known as Rhizoctonia blight) is a serious fungal lawn disease that affects both warm and cool season grasses. In the spring, cool season grasses are at a higher risk during times with high humidity and moderate temperatures (45 to 70 F). A beautiful spring lawn can be quickly destroyed as the disease develops quite rapidly.

How to Identify Brown Patch

Brown patch often appears in rough circular patches varying from roughly 1-5 feet in diameter. When the disease conditions are favorable, it is not uncommon to see large areas of the lawn thinned out or killed. A close inspection of the grass will often reveal small, yellow spots on the grass blade with a dark brown outline.
Brown Patch Disease    Brown Patch on Grass Blade

What Causes Brown Patch?

Brown patch is caused by an infection of the grass foliage and crown by Rhizoctonia fungi. Brown patch can occur in both warm and cool season grasses. In cool season grasses brown patch typically occurs in times with temperatures above 85F with high humidity. Night time and evening showers can increase the chances of brown patch disease developing. In cool season grasses, it is more common during times with moderate temperatures.

How Can I Treat Brown Patch Disease in My Lawn?

Maintaining good cultural practices can go a long way in preventing brown patch disease:
  • Water your lawn only when needed (do not overwater)
  • Water your lawn in the morning
  • Remove grass clippings after mowing if weather is humid (this will prevent spread of the disease)
  • Mow the lawn regularly to prevent excess thatch build up
  • Ensure your lawn has proper drainage to avoid excessively damp areas or puddles
  • Prune trees and bushes if your lawn is very shaded
  • Keep your mower blade shape for a clean cut
If you notice brown patch disease on your lawn, do not hesitate to contact your local Weed Man. They will be able to recommend steps for treatment. An application of Weed Man’s slow-release fertilizer can help prevent brown patch; however, fungicide applications can also be used for managing this turf disease.

Brought to you by Weed Man Lawn Care Knoxville, TN : we care for your lawn.