Asked April 07, 2021, 7:52 PM EDT
Waseca County Minnesota
Sometimes fairy rings develop in lawns especially in the spring during wet, cool weather.
There are three types of fairy rings:
type I: soil and thatch become hydrophobic and the grass dies; brown ring of dead grass
type II: rings on the lawn that are 2 – 8 inches wide with lush green grass
type III: mushrooms and puffballs are produced in the ring
white fungal mycelium can be found in thatch and soil for all three types
Reduce thatch with proper cultural practices. https://extension.umn.edu/lawncare/how-control-thatch-your-lawn
Mask fairy ring; water deeply and fertilize to stimulate growth of grass around ring.
For type II fairy rings, a wetting agent may be needed.
Control with fungicide drenches is inconsistent.
Soil replacement: remove soil about 20 inches to each side of the ring and up to 30 inches deep and replace with sterile soil. This is a very expensive management option.
Aerate your soil in the fall to reduce soil compaction and improve drainage.
Please read pages 19 and 20.