Sphagnum squarrosum
Sphagnum alaskense
rough peat moss, shaggy peat, sphagnum, spiky bog-moss, spread-leaf peat moss, spreading-leaf bog moss
green to red-brown; 2–3 superficial cortical layers.;
stem leaves shorter than branch leaves, ovate-lingulate to oblong-lingulate, 1.6–1.8 × 1–1.2 mm;
hyaline cells mostly nonseptate.
leaves to 1.7 × 1.2 mm; rarely hemiisophyllous;
hyaline cells nonseptate to occasionally septate, comb-lamellae absent.
long and tapering with distinct squarrose spreading leaves, often terete in tundra forms.
long and tapering.
larger than stem leaves, 1.9–2.8 mm, conspicuously squarrose from ovate-hastate base and abruptly narrowed 1/2–1/3 distance from apex into involute-concave acumen, often terete in tundra forms;
hyaline cells convex on both surfaces, non-ringed pores at ends and corners of cells, ringed pores on concave surface (4–8/cell) and nonringed pores (2–4/cell) on convex surface, internal commissural walls smooth or indistinctly papillose, chlorophyllous cells ovate triangular with widest part at or close to the convex surface.
broadly ovate, to 3 × 2.3 mm;
hyaline cells on proximal half of convex surface with elliptical pores along the commissures, often with ridges running parallel to long leaf axis on hyaline cell surface overlying chlorophyllous cells; chlorophyllous cells elliptical and just enclosed on both surfaces in transverse section;
end walls not thickened.
monoicous.
dioicous.
not seen.
17–30 µm;
proximal surface finely papillose, distal surface smooth with raised bifurcated Y-mark sculpture;
proximal laesura more than 0.5 spore radius.
unknown.
fascicles with 2 spreading and 2–3 pendent branches.;
branch stems with 1–2 layers of cortical cells.
fascicles with 2 spreading and 2 pendent branches.;
branch stems with hyaline cells non-ornamented, no or weak funnel-like projections on the interior end walls, often with large round pores on the superficial wall.
Sphagnum squarrosum
Sphagnum alaskense
In its typical robust form with strongly squarrose branch leaves, Sphagnum squarrosum is unmistakeable. Smaller forms such as occur in the higher mountains may be difficult to identify accurately without careful examination of microscopic details. In the tundra there sometimes occur large, terete forms of S. squarrosum but these are usually considerably more robust than S. teres. See also discussion under 14. S. strictum.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Sphagnum alaskense most resembles S. magellanicum and S. centrale in its chorophyll cell cross section. The cross section characteristic is most similar to that of S. centrale but S. alaskense lacks thickened walls. Sphagnum alaskense also apparently does not have any range overlap with S. centrale, the latter being more of a boreal forest species. Sphagnum alaskense occurs in more open and less mineral rich sites near the coast. Sphagnum magellanicum has more well-enclosed chlorophyll cells and usually has some purplish coloration, whereas S. alaskense often has a quite distinctive pinkish brown color which, along with its often large flattened capitula, can give it a distinctive look in the field.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
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