The class Sphagnopsida consists of only one genus, Sphagnum, which is only distantly related to other classes of bryophytes. However, they are similar in respect to their life cycle and mode of growth.

Sphagnum spp. are ecologically important species in bogs around the world. The hyaline cells of peat mosses are able to hold large quantities of water. This holding capacity is important in retaining moisture in bogs and controlling runoff. The ion exchange capability of Sphagnum is important in maintaining the acidic conditions common to bogs.

Sphagnum capillifolium is a widespread and abundant taxon. It forms hummocks in the drier parts of acid bogs. It may also grow in damp, acidic woodlands. S. capillifolium is usually found in shaded habitats but may grow in open areas.

The gametophyte is small and stiff, but variable in height. There is a well-developed capitulum, which is round to hemispherical. The plants are pale-green to green, often tinged with red, especially in the lower portion of the stem. Branches are arranged in fascicles of four. The two spreading branches are approximatly 5.0 mm in length and end abruptly. The pendant branches are longer (15 mm), tapering, and are tightly appressed to the stem. The stem leaves are erect and appressed. The leaves are 1.0-1.8 mm long with an involute apex. The branch leaves may be five-ranked and are usually erect and spreading. These leaves are lanceolate and usually less than 1.4 mm long. Plants may be monoecious or dioecious. The antheridial bracts are crimson and resemble the branch leaves.

There are two varieties of S. capillifolium, capillifolium and tenellum. The variety tenellum posses a stellate capitulum. The plants are shade intolerant and posses more red coloration than capillifolium.

Sphagnum capillifolium has a circumboreal distribution. In North America it is found from Labrador to Alaska to North Carolina and Colorado.

Literature Cited

Crum, Howard. Mosses of the Great Lakes Forest. Ann Arbor: University of Michigan, 1983.

Daniels, R. E. and A. Eddy. Handbook of European Sphagna. Huntingdon, Great Britain: Institute of Terrestrial Ecology, 1985.

McQueen, Cyrus B. Field Guide to the Peat Mosses of Boreal North America. Hanover, NH: The University of New England Press, 1990.

Written by Harold Gilbert