Necrotic ring spot is a disease of which turfgrass?

• A. Bermuda grass
• B. Zoysiagrass
• C. Kentucky bluegrass
• D. Tall fescue

Answer: (C)

Necrotic ring spot mainly affects cool-season turfgrasses, with Kentucky bluegrass being the grass most commonly associated with this disease. The fungus that causes it attacks roots and crowns, producing circular patches of dead tissue that often have a green center. These rings vary in size and are a characteristic symptom you’d look for on Kentucky bluegrass, especially under conditions of heat and moisture. Warm-season grasses like Bermuda and Zoysiagrass are much less typical hosts, and while tall fescue is a cool-season grass, it is not the species most commonly linked to this disease. Recognizing the ring pattern on Kentucky bluegrass helps you identify necrotic ring spot rather than other turf diseases.