WSU Extension

Hortsense

Lawn and Turf : Fairy ring and mushrooms
(revision date: 3/12/2014)


Biology
Several species of fungi can cause fairy rings in lawns. The common symptoms may include a ring of dead grass with darker green grass and mushrooms on the inside and/or the outside of the ring, circular patches of darker green grass, or rings of mushrooms or puffballs appearing with or without other symptoms. Mushroom rings most commonly appear in the spring or fall when adequate moisture is present. The type of fairy ring which causes dead rings is the most damaging. The fungus feeds on decomposing organic matter such as dead tree roots and undecomposed bark mulch in the soil and makes water penetration difficult. Fairy rings are more severe on sandy soil with low fertility. Grass inside the rings may be weakened or killed and replaced with weeds and weedy grasses. Fairy rings may disappear suddenly.
Management Options

Non-Chemical Management
  • Provide proper culture, including deep, infrequent waterings and adequate fertilization.
  • Rake and loosen soil in affected areas. Aerate soil and water the area deeply. A grass-type wetting agent can be used to help rewet the soil.
  • After rewetting, reseed affected areas and fertilize and water properly.
  • Remove the sod, mix soil in affected areas in the upper 6 to 8 inches of soil with a rototiller, and reseed or put new sod in the area.
Select non-chemical management options as your first choice!

Chemical Management

None recommended

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Caption: Fairy ring and mushrooms
Photo by: R.S. Byther
Caption: Fairy ring and mushrooms
Photo by: R.S. Byther