The Alaska Vegetation Classification - Alaska Geobotany Center ...

Communltles-Eriophorrn russeolum-E. scheuchzeri (Wilson and Underwood1979). €riophormspp.-Menyanthes trifoliata (Dachnowski-Stokes 1941). Eriophorumrusseolum-Carex kelloggii-Calamagrostis canadensis (Heusser 1960). Eriophorumrusseolum-Carex limosa-Calamagrosfis canadensis (Cooper 1939, Streveler andothers 1973). Carex limosa-C. chordorrbiza (Calmes 1976, Drury 1956). Tarexlimosa-C. capillaris (Viereck 1970b). Carex pluriflora (Hulten 1960). Carex pluriflora-Eriophorm russeolum (Bank 1951). Carex kelloggii-C. canescens (Shacklette1961 a). Carex livida-Menyanfhes trifoliata (Hogan and Tande 1983).lll.A.3.k. Subarctic Lowland Sedge-Moss Bog MeadowDescription-These communities are dominated by mosses, principally Sphagnumspp. (fig. 68). Low sedges, such as those listed above for sedge-bog meadows, aregenerally present and usually codominant. The aspect is of low slender sedges andother herbs growing out of a matrix of sphagnum mosses. Low shrubs and lichensmay be present or absent but are not dominant. Andromeda polifolia and Vacciniumoxycoccos are low, delicate shrubs that are commonly present, though they providelittle cover. Widely scattered stunted trees may be present. Plant cover is completeor nearly so.Distribution and site characteristics-The subarctic lowland sedge-moss bogsoccur throughout the nonarctic parts of the State on peat in filled-in lakes and otherdepressions or on slopes where precipitation is adequate (Aleutian Islands, southeasternAlaska, and parts of south-central Alaska) and may form floating mats. Thesubstrate is wet acidic peat at least 30 centimeters (12 in) thick and frequently isdotted with small pools. The reaction of the peat is generally pH 4.0 to 5.5, thoughvalues as high as 6.2 have been reported. The pH of the wafer in the pools is usuallyslightly higher than that of the associated peat. Permafrost is generally absent, butisolated pockets may be present under moss hummocks in interior Alaska.Successional status-Floating mats of these communities may advance into shallowlakes lo replace marsh or aquatic vegetation. Continued peal accumulation in sedgebogmeadows combined with invasion of sphagnum mosses also can result in establishmenlof these sedge-moss bogs. Continued bog development may yield surfaceconditions resulting eventually in shrub or forest invasion of the bog.Figure GB--Subarctic lowland sedgemossbog meadow dominated by thesphagnum mosses Sphagnum luscumand S. warnstofii, the sedges Carexpaucinora, C. limosa. and Eriophorumangustifolium. and the low shrubsAndromeda polilolia, Betula nana, andVaccinium oxycoccos in southwestAlaska.188