Date of this Version



© 1990, The Board of Regents of the University of Nebraska on behalf of the University of Nebraska–Lincoln Extension. All rights reserved.


This NebGuide describes the causes, predisposing conditions, and symptoms of summer patch and necrotic ring spot, and provides recommendations for their control.

Research since 1980 has resulted in considerable progress in identifying causes of the "patch"-type disease of turfgrass. Two of the most destructive patch diseases of turfgrasses are summer patch and necrotic ring spot.

Both summer patch and necrotic ring spot are present in Nebraska turfs. Unfortunately, necrotic ring spot and summer patch cause identical symptoms and cannot be distinguished in the field, and identification in the laboratory is time-consuming (3-6 months) and laborious.