A Montane Kobresia myosuroides Fen Community Type in the Southern Rocky Mountains of Colorado, U.S.A.

Abstract

Kobresia myosuroides is a well-known circumpolar taxon and an important community dominant in many arctic and alpine regions of the Holarctic. It typically occurs on xeric to mesic, windblown ridges, and in meadows and heaths. In this paper we report on K. myosuroides populations more than 700 m below treeline in extreme rich fens in South Park, Colorado. The distinctive Thalictrum alpinum–K. myosuroides community type includes many wetland plant species and appears to be a unique fen community, endemic to South Park. The K. myosuroides populations in South Park are a well-marked race, or ecotype, forming tussocks up to 400 mm tall, with culms averaging 300 mm in height, and leaves more than 200 mm in length. These communities and populations are threatened by the peat mining industry.