Brown patch disease occurs in lawns during long periods of leaf wetness. This most commonly occurs during the summer when night temperatures are 68 degrees Fahrenheit or above combined with extended periods of high relative humidity and temperatures.
Symptoms
Brown patch causes a leaf spotting that results in circular brown patches from 6 inches to 2 feet in size, and thinned turf. Leaf spots are often irregular and have a reddish-brown border. Small patches can grow together to form large areas quickly when weather conditions for the disease are ideal. All turf grasses are affected, especially tall fescue and ryegrass. Mature turf is rarely killed. One-year-old stands of tall fescue under severe conditions can be killed.
Cultural Control
Not watering daily and watering at the correct times can help slow down and alleviate the disease.
Treatment
A fungicide treatment is recommended. Ask your local lawn and garden retailer for assistance.