Necrotic ring spot and summer patch are two patch diseases that can be very destructive when Kentucky bluegrass is grown under intensive management. These diseases become a concern in lawns when improper management practices, such as close mowing, promote disease development.
Previously called Patch Diseases in Kentucky Bluegrass Lawns, this fact sheet is newly revised. Symptoms (and how to distinguish between these two similar diseases), causes, disease development, and management tools are provided.
Necrotic Ring Spot and Summer Patch in Kentucky Bluegrass Lawns (PPFS-0R-T-06) is available online.
For additional publications on turfgrass diseases, visit the UK Plant Pathology Extension Publications webpage.
By Cheryl Kaiser, Plant Pathology Extension Support and Paul Vincelli, Plant Pathology Extension Specialist