Lawn Disease – Red Thread

(Laetisaria fuciformis)

Red Thread is a turfgrass disease caused by the fungus Laetisaria fuciformis. Red Thread affects all turfgrass species in the northern United States. Most damage occurs during mid to late spring and late summer to early fall.      

Identifying Red Thread -

Red Thread can be identified by patches forming in your lawn that are reddish-brown and 1 to 4 inches in diameter. In some cases these patches can be up to 2 feet in diameter. A gelatinous mass of pink mycelium can also be found on water soaked leaves. This pink mycelium is where the disease gets its name “Red Thread”.

This disease is found wherever there are extended periods of cool, wet weather.

Conditions for Red Thread Infection-

Red Thread can only lead to an infection in your lawn if all of the following conditions are present:

1. Pathogen – Red Thread (Laetisaria fuciformis)

2. Host – All turfgrass species

3. Environment – Wet climates with temperatures ranging from 40-85 degrees Fahrenheit and low nitrogen soils

Red Thread Control -

Cultural disease control practices create favorable conditions for a healthy lawn, and often create unfavorable conditions for the growth of Red Thread. Environmental conditions cannot be changed, but cultural practices performed by the homeowner can be modified to lessen the chance of extensive damage from Red Thread. Scotts LawnService can help determine a plan for preventing and controlling Red Thread in your lawn.

For Red Thread control and treatment, Scotts recommends the following cultural control tips:

  • Mow turf frequently at the proper height with a sharp blade
  • Maintain adequate levels of nitrogen and a balanced fertility program
  • Apply adequate amounts of phosphorus and potash
  • Maintain soil pH at 6.5 to 7.0
  • Reduce shade and increase air flow
  • Infrequent deep watering is recommended verses frequent shallow watering

Scotts LawnService has professional products that can prevent and control lawn diseases when cultural control practices are not effective.

Scotts LawnService is the trusted industry leader for professional quality lawn care. Our exclusive lawn care products include premium grass seeds and professional-grade fertilizers; our lawn service teams are comprised of highly trained, industry-certified professionals. Contact a representative today for Red Thread control options available in your area and to learn how you can enjoy a lush, thicker lawn that only Scotts LawnService can deliver.