We are getting reports of Large Patch and Spring Dead Spot showing in lawns throughout the South and Southeast regions. These diseases were formerly called Brown Patch, a disease that affects cool-season grasses in the middle of the summer.
These diseases begin to infect turf in the fall and the symptoms show in the late spring to early summer as the lawns come out of winter dormancy. Brown Patch on cool-season grasses begins to infect the turf during periods of high heat and humidity and the symptoms immediately show on the lawn.
Large Patch Symptoms and Grasses Commonly Affected
Large Patch is mainly a disease of Centipede, Zoysia and St, Augustine lawns. Spring Dead Spot affects Bermuda grass. The infection begins to develop when soil temperatures drop to about 70 degrees in the fall. The symptoms may show in the fall, but more likely they will show during the spring of the following year, especially during cool, wet periods. The symptoms are very noticeable as these grasses start greening up.
Large patch is more likely to show up on lawns that receive excessive nitrogen fertilization in the fall and spring, have excessive thatch layers, have been overwatered or been mowed too low. Centipede grass is most susceptible to the disease, followed by Zoysia, St Augustine and Bermuda grass. Bermuda grass is rarely affected by the disease and will quickly recover if it does get the disease.
Spring Dead Spot can take 3 to 5 years to become established in a new Bermuda grass lawn. If left untreated, the disease will become more severe each year. The disease attacks all parts of the plant, but does not kill it directly, but allows the plant to become more susceptible to freeze injury during the winter.
Prevention and Treatment
Following good cultural practices of proper mowing, deep and infrequent watering, proper lawn fertilization and annual core aeration will help prevent the disease from occurring. Avoid fertilizing the lawn after the middle of September and don’t fertilize until the grasses begin greening up in the spring.
There are fungicides that work very well on these diseases, but require two applications in the fall, 30 days apart, when soil temperatures drop to below 70 degrees. If you think that your lawn may have Large Patch or Spring Dead Spot, contact your local Spring-Green office to have your lawn checked. They can help develop a program that will benefit your lawn and help to prevent the re-occurrence of Large Patch.
If you have any questions, contact your local neighborhood lawn care professional at Spring-Green.