What is Brown Patch?

Rhizoctonia Blight or the more commonly known name of Brown Patch disease is a hot weather disease that can occur on all types of North Texas turf; however, it is most damaging to St Augustine, but can affect Zoysia grass too. You tend to see injury in late summer when the nighttime temperatures begin to decrease. Brown Patch often first appears as rough circular patches varying roughly in size from 1-5 feet. 

In the early morning hours, fine strands of grayish cobwebby fungal growth called mycelium may be evident (pictured below) – it will appear as dew on the lawn. This quickly disappears as the mycelium dries or if you touch it. Individual leaves on the turf die back from the tip and can turn dark green, then yellow as they wither and decay.