The Science of Fairy Rings
Fairy Rings are fungi are in the soil to break down old tree stumps, roots, logs and other larger pieces of organic material in the soil below the lawn. The uniform outward growth of the fungus results in the development of rings. Once the material is exhausted, the fairy ring will disappear. This may take many years. Several fairy rings may appear close together, especially in lawns that were previously wooded areas.
Types and Treatments of Fairy Rings
When these fungi digest the organic material, they expel nitrogen. This is why the grass looks seemingly happy in the fairy ring. However, sometimes the opposite effect can happen, which depletes soil nutrients and produces toxic levels of hydrogen cyanide.
Approximately 50 species of fungi in the Basidiomycetes family are known to cause fairy rings in turf; however, there are only three outcomes:
- Variety A: The most inconspicuous type of fairy ring. The dark ring of grass is absent. Only parts of the ring will show fruiting bodies (mushrooms) at different times of the year, mostly during wet springs.
- Remove the mushrooms to help retard the spread in the area. Don’t over-water.
- Variety B: It’s the dark green rings, with or without mushrooms, which identify these varieties of fairy rings. At worst, this type of ring can appear unsightly with its lush growth, accompanied with mushrooms.
- Remove any mushrooms and use a balanced fertilizer to green up the rest of the lawn so the ring is not as obvious.
- Variety C: This variety of fairy ring is the most destructive and damaging as it produces a ring of dead grass. The dead area can contain fruiting bodies. Pull a soil profile from the dead area, white thread-like structures called mycelia will be visible in the soil. Mycelium is hydrophobic. Because of this property, it causes water to move away from the circle, thus drying out the grass.
There are really no fast cures for fairy rings that aren’t extreme. Digging up the area to remove the organic matter the fungi is feeding on, along with all of the adjacent soil is one method. According to some scientists, fairy rings do not cross. Some have said that digging up soil from one fairy ring and exchanging it for another has worked. Spraying fungicides are ineffective and a waste of money.
It is best to just be proactive in how you maintain the lawn. Do not over-water or over-fertilize, and be sure to aerate in the spring.
There’s another theory about how fairy rings are created…
Fairies create the circles by dancing within them.
Some cultures believe these circles to be dangerous to humans. Those violating fairy perimeters become invisible to those outside and may be unable leave the circle. The fairies then force the intruder to dance till exhausted, dead or in the throes of madness.
The only safe way to investigate a fairy ring is to run around it nine times, under a full moon and in the direction of the sun. Doing this permits the runner to hear the fairies dancing underground.
Other cultures still believe in fairy activity and that fairy rings are omens of good fortune. Some legends see fairy circles as places of fertility and fortune. The Welsh believe that mountain sheep eating the grass from a fairy ring flourish and crops sown around tend to grow better. Irish folklore believe fairy rings are gateways into Elvin kingdoms.