Necrotic Ring Spot
Necrotic Ring Spot Information
Scientific Name: Leptosphaeria korrae
Turfgrass host: Annual Bluegrass, Kentucky Bluegrass, rough bluegrass, fine-leaf fescue
Time of Year: April thru October
How To Identify Necrotic Ring Spot
Necrotic Ring spot is cause by the fungus Ophiosphaerella korrae and is a serious disease for Kentucky Bluegrass. A clear sign that you have Necrotic Ring spot in your lawn is that you first have dead turf ranging from 2 to 12 inches in diameter. These spots than grow together, forming streaks or circles in your turf. Necrotic ring spot favors warm, wet weather and many times is found by driveways and sidewalks.
How to get rid of Necrotic Ring Spot
First, you can use resistant Kenucky bluegrass varieties in order to stop the Necrotic Ring spot from taking over your lawn. Secondly, make sure your turfgrass is getting enough nitrogen, water, and is mowed higher than 2.5 inches. Fungicides that will cure Necrotic Ring Spot include thiophanate and azoxystrobin. For the best results, make sure you water your lawn before applying the fungicide.