Size, age, and insights into establishment, dynamics and persistence of fairy rings in the Laramie Basin, Wyoming

Abstract

Aerial photos and Google Earth images of the Laramie Basin in Wyoming were used to measure size, and calculate species-specific growth rates and ages for 304 rings comprising eight species of fairy ring forming fungi. Estimated age was used to explore establishment, dynamics and persistence in relation to historic precipitation and drought data. Size of fairy rings ranged from 4 to 272 meters, and age from 15 to 522 years. 90% of all rings were younger than 80 years. Species-specific growth rates varied from 0.131 to 0.364 meters per year. All fairy ring species became established over a wide range of precipitation, although most rings established during years with 25–30 centimeters of precipitation. Little correlation was observed between establishment and precipitation patterns for some fungi, however others exhibited a significant relationship between year of establishment and both August precipitation and the Palmer Modified Drought Index. Expansion of one large ring was followed for 75 years. These data demonstrate that turnover in fairy rings is quite high and that fairy ring fungi can establish over a wide range of moisture levels.