Stems appear to live for definite periods (about 10 years of spore production), then senesce and the entire plant dies.

New stems produced by gemmae, which fall at base of older plant.

Mature portion of stem with markedly small leaves.

Leaf margin entire with occasional small papillae formed by marginal [3]Restricted to acidic rock at high elevations along the lower Appalachians, and to northern latitudes elsewhere, generally near the Canadian border in Vermont, Maine, and Michigan, and up into the Canadian Shield.

[3] Acidic rock, occasionally exposed cliff faces.