Crop Circles

One week later- Click to e

This spring we have noticed several crop circles in the lower field as the grass started to green up.  One was a perfect circle 36 feet in diameter while the other one was about 20 feet and an incomplete "C" shape.  We have never noticed them in the past, but probably just missed them.  They can be subtle at first unless you ride on the higher ground above them.

I am calling these phenomena natural "crop circles" for lack of a better word.  Look up the term in Wikipedia and you will find complex geometric designs and a host of theories on how they occur.  A skeptic would think of creative people with equipment while others are sure that they are from pranksters from outer space.

I suspect ours are caused by a fairy ring fungus.  A network of mycelia in the soil can expand each year into a bigger circle and affect the fertility of the plants.  It can be manifested in increased growth or dead zones which are symmetrical. This phenomenon is well described below in this colostate.edu resource.

"Fairy rings are reported to be caused by many (60) different soil-inhabiting fungi of the class Basidiomycetes. These fungi can cause the development of rings or arcs of deep green grass as well as unthrifty or dead grass. Rings may vary in size from a few inches to 200 feet (60 meters) or more in diameter with an annual radial growth of 3 inches (7.6 cm) to 19 inches (48 cm) depending on grass, soil and weather conditions."

I have only seen one other fairy ring, one that was discovered by our mycologically inclined friend Mark Bower.  It was in his woods and with all the understory growth it defied the camera.  Fairy ring fungi are covered in this Wikipedia article.

Fairy Ring- Wikimedia

The fruiting bodies of the fungi can crop up in a naturally occurring ring or arc of mushrooms. The diameter of the circles can grow or eventually stabilize in diameter.  Fairy rings can occur in forested areas such as Mark's or in grassy fields.  They may be seen as mushrooms sprouting in a circular pattern or just by a ring of dead or dark green grass like ours.