Necrotic Ring Spot is a widespread disease of cool season turfgrasses. It appears in the Rocky Mountain area between May and mid-October.

It's a serious disease of Kentucky Bluegrass and has been increasing on Bentgrass, annual and rough Bluegrasses, and Fine Fescues. At NaturaLawn of America, we've developed a complete Necrotic Ring Spot treatment program specifically targeting the destructive effects of Necrotic Ring Spot disease.

Symptoms of Necrotic Ring Spot:

Circular patches of infected turf may develop whenever turf is under stress.
Patches first appear as small, light green spots 2-4 inches in diameter, but may exceed 3 feet.
As turf succumbs to infection, the leaves turn reddish brown to bronze and then fade to a light straw color.
All of the plants in a patch may die, resulting in a sunken or crater-like depression. It is not uncommon for the turf around the edges of the infected area to be greener in color.
The spread of Necrotic Ring Spot is stimulated by turf under stress, either by cool, wet weather conditions or by heat and drought conditions. Both of these conditions have been known to intensify the infected areas.

Necrotic Ring Spot Disease Cycle:

Necrotic Ring Spot is in the soil and is most active when the temperature is 68-82° F. Activity normally begins in early May and is active until mid-October. Recovery is slow, and severely infected plants are easily removed from the turf because of the extensive rotting of the roots. Re-sodding the disease areas may not be an alternative since there are some cases of Necrotic Ring Spot reappearing in the new sod. Heavy soil compaction also contributes to the disease.

So how do you get rid of Necrotic Ring Spot?