Necrotic Ring Spot

Pathogen: Ophiosphaerella korrae

Host: Annual Bluegrass, Kentucky Bluegrass, Fine Fescue, Rough Bluegrass

Environmental Requirements: root infection occurs during cool wet weather, symptom expression during heat and drought stress

Stand Symptoms: “frog-eyes” of wilted grass that will collapse and die out

Plant Symptoms: purpling of the plant

Fungal Signs: dark brown to black ectotrophic hyphae on the roots and crown

Environmental Modification: water deeply and infrequently, lower pH, aerify, use a fall fertility program

Plant Resistance: plant resistant varieties

Stand Symptoms


Fungal Signs