Bigelow's sedge meadow (S1)
Bigelow’s sedge meadow occurs at high elevations in the Presidential Range, and is most abundant on the north and west slopes of the cone of Mt. Washington, presumably where cloud-intercept and precipitation are greatest. The frequently cloudy conditions of these mountains are favorable for Bigelow’s sedge (Carex bigelowii) to dominate to the near exclusion of other species, in part because of its photosynthetic efficiency in low-light situations. There is a low diversity and abundance of all other species, but Bigelow's sedge is strongly dominant. Due to the extreme exposure of these sites, winds are strong and snow cover is low in winter. These meadows are best developed between 5,800–6,200 ft. elevation. They rarely occur outside the Presidential Range, and when they do they are small.
Soils consist of a shallow, organic-rich A horizon turf (0–8 cm) over gravelly or stony sandy loams. Although soils are well drained, soil moisture availability remains high due to precipitation and cloud-interception, and thus reduced solar radiation and evapotranspiration.
Among mesic, well drained alpine tundra communities of the Presidential Range, Bigelow’s sedge meadows occur in the harshest, most windblown settings. The other extreme is marked by alpine heath snowbanks, which occur in more protected areas with longer-lasting snow cover. The central part of this exposure gradient is occupied by sedge - rush - heath meadows (the most common community in the Presidential Range’s alpine zone).
Characteristic Vegetation: Bigelow’s sedge (Carex bigelowii) is the dominant species. Other low-growing alpine species are scattered and subordinate, and include mountain sandwort (Minuartia groenlandica), mountain cranberry (Vaccinium vitis-idaea), alpine bilberry (Vaccinium uliginosum), and highland rush (Juncus trifidus). Mosses and lichens are common, and include Polytrichum juniperum var. alpestre, Calliergon stramineum, Cetraria islandica, and Cetraria mitis.
Good examples of this community occur on the northwest side of the peak of Mt. Washington and on Mt. Jefferson's Monticello Lawn. The community is mostly restricted to the Presidential Range, but may occur in small patches on some outlying peaks.
Bigelow’s sedge meadows frequently occur along with other alpine communities as part of a larger alpine tundra system.
Bigelow's sedge meadow on Mt. Jefferson (photo by Ben Kimball)
Bigelow's sedge (Carex bigelowii) in the alpine zone (photo by Ben Kimball)
Bigelow's sedge meadow on Mt. Washington (photo by Dan Sperduto)
Bigelow's sedge (Carex bigelowii)
(photo by Ben Kimball)