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rough peat moss, shaggy peat, sphagnum, spiky bog-moss, spread-leaf peat moss, spreading-leaf bog moss

Habit Plants robust, stiff; green, pale green, yellow-green; large terminal bud; typically as loose carpets in coniferous forests. Plants moderate-sized, weak-stemmed, lax; yellowish to golden brown; forming loose carpets; branches loosely imbricate.
Stem(s)

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 short-rectangular, 0.8–1.1 mm, hyaline cells mostly non-septate and absent comb-fibrils.

Branches

long and tapering with distinct squarrose spreading leaves, often terete in tundra forms.

Branch leaves

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.

ovate to ovate-elliptic, 1.4–1.8 mm;

hyaline cells on convex surface with numerous pores along the commissures;

comb-lamellae obvious only in proximal 1/2 of leaf; chlorophyllous cells broadly triangular in transverse section and well-enclosed on the convex surface.

Sexual condition

monoicous.

dioecious.

Spores

17–30 µm;

proximal surface finely papillose, distal surface smooth with raised bifurcated Y-mark sculpture;

proximal laesura more than 0.5 spore radius.

(22) 24–27(–28) µm, surface granulate.

Branch

fascicles with 2 spreading and 2–3 pendent branches.;

branch stems with 1–2 layers of cortical cells.

fascicles with 2 spreading and 1–2 hanging branches.;

branch stems with hyaline cells non-ornamented, no or weak funnel-like projections on the end walls of cortical cells, cortical cell walls usually with large round pores.

Sphagnum squarrosum

Sphagnum imbricatum

Phenology Sporophytes abundant, capsules mature early to mid summer.
Habitat Forming loose carpets in rich habitats such as wet coniferous forests, Thuja swamps, karrs, medium fens, and stream margins Ecology poorly known
Elevation low to high elevations moderate elevations
Distribution
from FNA
AK; AZ; CA; CO; CT; IA; ID; IL; IN; MA; ME; MI; MN; MT; NC; NH; NJ; NY; OR; PA; SD; TN; VT; WA; WI; WV; WY; AB; BC; MB; NB; NF; NS; NT; NU; ON; PE; QC; SK; YT; Greenland; Eurasia; Pacific Islands (New Zealand)
[WildflowerSearch map]
from FNA
AK
Discussion

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.)

K. I. Flatberg (1984) considered Sphagnum imbricatum to be East Asian in distribution but a recent collection in Selawik National Wildlife Refuge places it in the North American flora. It will undoubtedly be found elsewhere. Sphagnum imbricatum is closest in morphological detail to S. steerei, but the latter is a very dark colored and densely branched species whereas S. imbricatum is quite light in color and not particularly dense.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 27, p. 59. FNA vol. 27, p. 52.
Parent taxa Sphagnaceae > Sphagnum > sect. Squarrosa Sphagnaceae > Sphagnum > sect. Sphagnum
Sibling taxa
S. affine, S. alaskense, S. andersonianum, S. angermanicum, S. angustifolium, S. annulatum, S. aongstroemii, S. arcticum, S. atlanticum, S. austinii, S. balticum, S. bartlettianum, S. beothuk, S. bergianum, S. brevifolium, S. capillifolium, S. carolinianum, S. centrale, S. compactum, S. contortum, S. cribrosum, S. cuspidatum, S. cyclophyllum, S. fallax, S. fimbriatum, S. fitzgeraldii, S. flavicomans, S. flexuosum, S. fuscum, S. girgensohnii, S. henryense, S. imbricatum, S. inexspectatum, S. inundatum, S. isoviitae, S. jensenii, S. junghuhnianum, S. kenaiense, S. lenense, S. lescurii, S. lindbergii, S. macrophyllum, S. magellanicum, S. majus, S. mcqueenii, S. mendocinum, S. microcarpum, S. mirum, S. mississippiense, S. molle, S. obtusum, S. oregonense, S. orientale, S. pacificum, S. palustre, S. papillosum, S. perfoliatum, S. perichaetiale, S. platyphyllum, S. portoricense, S. pulchrum, S. pylaesii, S. quinquefarium, S. recurvum, S. riparium, S. rubellum, S. rubiginosum, S. rubroflexuosum, S. russowii, S. sitchense, S. splendens, S. steerei, S. strictum, S. subfulvum, S. subnitens, S. subsecundum, S. subtile, S. talbotianum, S. tenellum, S. tenerum, S. teres, S. torreyanum, S. trinitense, S. tundrae, S. viride, S. warnstorfii, S. wilfii, S. wulfianum
S. affine, S. alaskense, S. andersonianum, S. angermanicum, S. angustifolium, S. annulatum, S. aongstroemii, S. arcticum, S. atlanticum, S. austinii, S. balticum, S. bartlettianum, S. beothuk, S. bergianum, S. brevifolium, S. capillifolium, S. carolinianum, S. centrale, S. compactum, S. contortum, S. cribrosum, S. cuspidatum, S. cyclophyllum, S. fallax, S. fimbriatum, S. fitzgeraldii, S. flavicomans, S. flexuosum, S. fuscum, S. girgensohnii, S. henryense, S. inexspectatum, S. inundatum, S. isoviitae, S. jensenii, S. junghuhnianum, S. kenaiense, S. lenense, S. lescurii, S. lindbergii, S. macrophyllum, S. magellanicum, S. majus, S. mcqueenii, S. mendocinum, S. microcarpum, S. mirum, S. mississippiense, S. molle, S. obtusum, S. oregonense, S. orientale, S. pacificum, S. palustre, S. papillosum, S. perfoliatum, S. perichaetiale, S. platyphyllum, S. portoricense, S. pulchrum, S. pylaesii, S. quinquefarium, S. recurvum, S. riparium, S. rubellum, S. rubiginosum, S. rubroflexuosum, S. russowii, S. sitchense, S. splendens, S. squarrosum, S. steerei, S. strictum, S. subfulvum, S. subnitens, S. subsecundum, S. subtile, S. talbotianum, S. tenellum, S. tenerum, S. teres, S. torreyanum, S. trinitense, S. tundrae, S. viride, S. warnstorfii, S. wilfii, S. wulfianum
Synonyms S. squarrosum var. imbricatum
Name authority Crome: Samml. Deut. Laubm., 24. (1803) Russow: Beitr. Torfm., 99. (1865)
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