Sphagnum molle |
Sphagnum platyphyllum |
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sphagnum |
flat-leaf peat-moss, sphagnum |
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Habit | Plants moderate-sized, soft and lax when wet, stiff when dry, typically very compact, capitulum flat and usually large; pale whitish, yellowish or purplish, occasionally a deep purple-red; without metallic sheen when dry. | Plants small to moderate-sized, unbranched or sparsely branched; green, golden brown to brown, capitulum small with a large and conspicuous terminal bud. |
Stem(s) | leaves quite variable in shape, elongate-lingulate to ovate, broadest above the middle, 1.9–2.5 mm, slightly concave, straight; apex broad and toothed; hyaline cells narrowly rhomboid, 0–1-septate, distal portion fibrillose, convex surface with membrane pleats, concave surface with 1(2–3) oblong membrane gaps. |
leaves broadly ovate, 1.2–2.2 mm; straight; apex rounded; hyaline cells non-septate, convex surface with numerous small pores (less than or equal to 1/6 cell diameter) forming a continuous row along the commissures, concave surface aporose or with a few scattered pores along the commissures and cell ends. |
Branches | rarely 5-ranked. |
short and blunt, sometimes lacking completely and plants simplex. |
Branch leaves | ovate, 1.6–2.2 mm, concave, straight; apex stiffly involute and broadly truncate with up to 8 teeth, border denticulate due to cell wall resorption and projecting cell walls; hyaline cells strongly bulging on convex surface and nearly plane on the concave surface, convex surface with narrowly elliptic pores along commissures grading from smaller pores near the apex to large rounded pores at base, concave surface with large round pores in proximal regions of leaf. |
broadly ovate, 1.4–2.5(–3) mm; straight; apex rounded; hyaline cells as in stem leaf. |
Sexual condition | monoicous. |
dioicous. |
Capsule | exserted, with few pseudostomata. |
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Spores | 27–33 µm, finely papillose on both surfaces with distinct bifurcated Y-mark sculpture on distal surface; proximal laesura less than 0.5 spore radius. |
23–35 µm; papillose on both surfaces, with indistinct Y-mark sculpture on distal surface; proximal laesura 0.5 spore radius or less. |
Branch | fascicles with 2 spreading and 1–2 pendent branches. |
fascicles of 1–3 branches, 1–2 of these spreading, branches usually not numerous. |
Sphagnum molle |
Sphagnum platyphyllum |
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Phenology | Capsules mature early to mid summer. | Capsules mature late spring to early summer. |
Habitat | Weakly minerotrophic and hygrophytic, poor fens and sand dunes, forming tight cushions among grasses and sedges in savannas, pine barrens, swamps, pond margins, and ditches where periodic dessication is common | Typically growing in minerotrophic habitats such as shores of lakes, ponds, streams, flarks of string mires, margins of open fens, especially seasonally flooded sites |
Elevation | low to high elevations | low to high elevations |
Distribution |
AL; DE; FL; GA; KY; LA; ME; MS; NC; NJ; NY; SC; TX; VA; LB; Europe |
AK; AZ; CA; CO; CT; IN; MA; ME; MI; MN; MT; NH; NJ; NY; OH; OR; RI; VT; WI; WY; AB; BC; MB; NB; NF; ON; QC; YT; South America; Greenland; Eurasia |
Discussion | The sporophytes of Sphagnum molle are common. This species is usually easily distinguished from other red species of sect. Acutifolia by its relatively large, straight, loosely spreading and unranked branch leaves. Sphagnum tenerum, the other red species of sect. Acutifolia to which it is most similar, has branch leaves that are quite imbricate. Microscopically, the denticulate-margined branch leaves are unmistakeable. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Sporophytes are uncommon in Sphagnum platyphyllum, which can be quite variable in size and the development of branch fascicles, with some forms even being simplex while other forms may have up to three branches per fascicle. The species can usually be recognized by the large stem leaves that are spreading and easily visible because of the scarcity of hanging branches. It should also be noted that in this species and S. contortum the 2–3-layered stem cortex is not an entirely consistent trait, as plants quite typical in all other respects are occasionally found with the cortex only 1-layered, at least in part. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 27, p. 95. | FNA vol. 27, p. 83. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | S. labradorense, S. tabulare | S. laricinum var. platyphyllum, S. contortum var. platyphyllum, S. subsecundum var. platyphyllum |
Name authority | Sullivant: Musc. Allegh., 205. (1846) | (Lindberg) Warnstorf: Flora 67: 481. (1884) |
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