The Habitats of Three Boreal Fen Mosses New to the Southern Rocky Mountains of Colorado

Abstract

Three borealfen mosses are reported new to the southern Rocky Mountains of Colorado. Scorpidium scorpioides (Hedw.) Limpr. occurs in extreme rich fens in the area of South Park. It occupies seasonal pools in high elevation mires where high pH and marl deposits occur. Paludella squarrosa (Hedw.) Brid. forms cushions in two rich fens above treeline on Guanella Pass where it is fed by water with nearly neutral pH. Sphagnum contortum K. F. Schultz occurs in two poor to intermediatefens in mires on the edge ofsmall moraine-dammedponds in Rocky Mountain National Park. It forms a continuous carpet at the water's edge where it is seasonallyflooded. All three species are new to the southern Rocky Mountains and occur in similar habitats to those described for these species in boreal mires. The presence of these species and knowledge of their ecology help elucidate the relationship between the southern Rocky Mountain and the boreal mire floras. The moss flora of the southern Rocky Mountain region is relatively well-known from the work of Flowers (1973) and Weber (1973). However, the flora of the fens (minerotrophic mires) has received surprisingly little attention. Most fen vegetation in this region is dominated by Carex spp., Eleocharis quinqueflora, and in some cases Salix spp. Thus, peat is largely derived from the roots and leaves of these plants. Mosses are not abundant in most fens and moss carpets are largely restricted to rich fens and fens with gently but constantly flowing water. Mosses that dominate the bottom layer of southern Rocky Mountain fens are also important in boreal peatlands and include Aulacomniumpalustre, Cam- pylium stellatum, Drepanocladus aduncus, and To- menthypnum nitens. This paper reports the discovery of three impor- tant boreal fen mosses from mires in the southern Rocky Mountains of Colorado and describes their habitats.