Large Patch

As spring advances and warm-season lawns green-up, the Plant Problem Clinic at Clemson University has been receiving many samples from lawns with large patch disease. Large patch, also known as brown patch, is caused by various species of the fungus, Rhizoctonia. Of the warm-season grasses, centipedegrass and St. Augustinegrass are particularly susceptible.

Large patch disease is prevalent in early spring and late fall. While symptoms of the disease may vary significantly depending on the type of grass and soil conditions, symptoms generally include somewhat circular, brown to gray-brown areas in the lawn (see below). These diseased areas can range from a few inches to several feet in diameter. Often the center of the patch recovers, resulting in a doughnut-shaped pattern.

Image depicts lawn with symptoms (i.e. large brown patches) of large patch disease.

For more information on large patch (brown patch) disease, the lawn care practices that help prevent it, and what fungicides are recommended for control, see HGIC 2150, Brown Patch Disease of Lawns.

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This information is supplied with the understanding that no discrimination is intended and no endorsement by the Clemson University Cooperative Extension Service is implied. All recommendations are for South Carolina conditions and may not apply to other areas. Use pesticides only according to the directions on the label. All recommendations for pesticide use are for South Carolina only and were legal at the time of publication, but the status of registration and use patterns are subject to change by action of state and federal regulatory agencies. Follow all directions, precautions and restrictions that are listed.