As the warm-season turfgrasses begin to green-up in the spring, symptoms of a disease known as large patch often become evident. This is a common disease of centipedegrass, St. Augustinegrass, zoysiagrass, and bermudagrass grown for lawns, landscapes, golf turf, and athletic fields. Centipedegrass and St. Augustinegrass are particularly susceptible to large patch.
Symptoms of large patch appear in roughly circular patches from 2 feet up to 10 feet or more in diameter. The affected turf will initially be orange, yellow, or reddish-brown in color but will then turn tan and collapse to the ground. The disease can spread rapidly to encompass large areas of turf, and distinct circular patches may not be obvious in these cases.
Fungicides are available for large patch control, but they are most effective when applied preventatively. The first application should be made in the late summer or early fall when soil temperatures decline to 70°F. One application will control minor cases of the disease, but two to three applications on a 4 to 6 week interval may be needed to control severe cases. Fungicides are not very effective in the spring once the symptoms of large patch appear. Curative applications will help to reduce further spread of the disease, but the affected turf will be very slow to recover.
For more information on large patch and preventative fungicide programs, please visit the following link: