Everyone is enjoying the cooler days and subtle changes from summer to fall. Daylight hours are shorter and there is that hint of crispness in the morning air. There are some subtle changes going on with our lawns, too.

When temperatures begin to cool the potential for large patch (Rhizoctonia solani) disease will increase. While most turf species can be affected by large patch, it is most prevalent in St. Augustine and Centipede lawns during the spring and fall.

Large patch, also called brown patch, is characterized by brownish to gray water-soaked and irregular circular areas that are a few inches to several feet in diameter. The disease usually attacks the base of leaf sheaths where they are joined to the stolons. If the disease becomes severe and is not controlled it will eventually attack the root system killing large areas of lawn.

Excessive nitrogen fertilization, leaf wetness and heavy thatch build-up tend to make turf more susceptible to brown patch. If your lawn has a history of brown patch, be on alert and prepare to treat with an appropriate fungicide.

Control is particularly important in the fall, as the turf will not have sufficient recovery time before it goes dormant. Weakened, thin areas in the lawn now, and throughout the winter, will only lead to more problems in the spring.

Rebecca Bates is an MSU Extension-Lincoln County agent, and can be reached at 601-835-3460 or by e-mail at rebecca.bates@msstate.edu.