Lawn and Turf: Anthracnose/Basal crown rot

categories: Lawn and Turf Lawn and Turf Diseases

revision date: 2023-04-12 12:00

Basal crown rot in lawn turf.
Basal crown rot
Photo by: R.S. Byther

Biology

Anthracnose of turfgrass is a fungal disease with two phases. Phase I affects the leaves and is active in the summer. Typical symptoms include yellow to tan or brown lesions on the blades of older leaves and sheaths, followed by small black fungal fruiting bodies on killed tissues. The fruiting bodies are covered with black hairs. The diseased grass appears as blighted or thinned areas a few inches to a foot or more in diameter. Warm, humid summer weather favors spread of the disease, especially on stressed lawns. Phase II occurs in fall and winter on basal portions of the stems. Leaves on affected stems turn yellow to orange-red beginning at the tip. Blighted areas of grass in this instance are typically small, seldom exceeding an inch in diameter. Grass wounded by aeration or other treatment is more susceptible to fall infection. The disease is more severe on bentgrass, annual bluegrass, and red fescues.

Management Options

Use Integrated Pest Management (IPM) for successful plant problem management.

Non-chemical Management

Select non-chemical management options as your first choice!

  • Provide proper culture. Adequate, balanced fertilization and deep, infrequent watering will help prevent disease. Water in the morning so grass can dry quickly.
  • Remove thatch and aerify lawns as needed to help reduce stress on plants.
  • For more information on proper care of lawns, including mowing heights and fertilizer recommendations, see EB0482E, Home Lawns.

Chemical Management

IMPORTANT: Visit Home and Garden Fact Sheets for more information on using pesticides.

Make applications when disease is first noticed. Do not repeatedly apply the same fungicide or fungicides with the same active ingredient as tolerant strains may result. Carefully check product labels.

Approved Pesticides

Listed below are examples of pesticides that are legal in Washington. Always read and follow all label directions.

Additional Images