Monday, September 5, 2011
Fairy Rings, Those Magic Things
Walking through our neighborhood, my son noticed this "fairy ring" and pointed it out to me. After hurricane Irene, I've noticed more mushrooms popping up in the area. A mushroom is simply the fruiting body of a larger, underground organism (I don't say "plant," because mushrooms are part of a fungus, which are genetically closer to animals than to plants). This underground organism is far larger than just the fruiting body. It is a fungal mycelium existing below the soil. Fairy rings, broad circles of mushrooms, can create circles of dead grass or circles of a deeper, darker green grass, in a suburban lawn. This is because some mycelia produce plant growth hormones causing rapid growth of grass. Under other conditions, the mycelia can coat the grass roots, killing it. Over time, a fairy ring can expand, some creating double rings or other shapes, often starting at a place where a tree once stood, and the stump remains below ground.
Fairy rings are highly resistant to chemical and other controls. Aerating the soil and replanting the grass might work, though the large mycelium may thwart your efforts. Keeping the soil saturated for 4 to 6 weeks can also help, but this in in itself can kill the grass and any trees or shrubs in or near the area (like the one in this photo above, just outside the ring). It may be that the very best thing you can do is enjoy the pretty sight (I find fairy rings very pretty) wait it out and see what happens over time.