Summer Patch & Necrotic Ring Spot

Summer Patch & Necrotic Ring Spot Turfgrass Disease

Hot weather diseases (over 75 F)

When will it appear?

1. Late spring-early summer
2. The fungus attacks soil at 70F
3. Excessive watering, heat stress, moisture, close mowing, high amount of thatch.
4. Heat and drought will intensify disease

Plants affected?

1. Kentucky/annual bluegrass
2. Fine Fescues
3. Creeping bentgrass

Symptoms?

1. Patches, circular with dead or stunted grass.
2. Patches not “greening” up fast in the spring
3. Known as “frogeye”, or “Fisheye”
4. Leaves may be tan or yellow
5. Leaves stunted and wilted
6. Roots and rhizomes may be dark and brittle and have black lesions.

Can you see the fungus?

NO