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bog haircap moss, hummock haircap, narrow-leaf haircap, polytrichum moss, slender haircap

awn haircap moss, polytrichum moss

Habit Plants slender, green to whitish green, dark brownish with age, in deep, compact tufts. Plants small to medium, glaucous green to reddish brown, in loose tufts.
Stems

6–12(–20) cm, simple, densely matted with wooly whitish to light-brownish tomentum.

(0.5–)1–4 cm tall, rather wiry, unbranched, comose at the tips, whitish tomentose only near the base.

Leaves

2–5(–6) mm, erect to closely appressed when dry, erect-spreading when moist;

sheath oblong-rectangular, brownish, ± abruptly contracted to the blade;

blade narrowly lanceolate, acuminate, flat, with sharply infolded margins;

marginal lamina 6–7 cells wide, 1-stratose, entire to finely crenulate above, membranous and transparent, abruptly infolded and enclosing the lamellae and overlapping towards the apex;

costa toothed abaxially towards the apex, short-excurrent as a short, reddish brown awn;

lamellae bluntly crenate in profile, 5–8 cells high, the marginal cells in section pyriform, thick-walled, ending in a thickened knob, end cells of lateral lamellae ovoid and scarcely thickened at the apex;

sheath cells 45–80 × 7–10 µm, elongate-rectangular (5–7:1), narrower toward the margin;

cells of the marginal lamina transversely elongate, shorter and obliquely oriented towards the margins, very thick-walled and colorless.

(2–)3–4 mm, erect, straight and slightly incurved when dry, erect-spreading when moist;

sheath ovate, ± contracted to the blade;

blade linear-lanceolate, turgid, with sharply infolded margins, the leaf apex abruptly contracted to the base of the awn;

marginal lamina 5–8 cells wide, 1-stratose, membranous, entire to finely serrulate toward the apex, enclosing the lamellae and overlapping in distal half or more;

costa typically smooth abaxially, long-excurrent as a spinulose-toothed, hyaline awn;

lamellae in profile crenulate-dentate to serrulate, with crenulations directed towards the leaf apex, (4–)6–8 cells high, the marginal cells in section conic to distinctly pyriform, terminating in a distinct knob, the marginal cells of the lateral lamellae ovoid, thinner-walled;

sheath cells 60–80 × 10–15 µm, elongate-rectangular (4–6:1);

cells of marginal lamina transversely elongated, ± irregular and sinuous, smaller toward the margins and obliquely oriented, especially approaching the apex, thick-walled.

Seta

2–4 cm, yellowish to reddish brown.

1–3 cm, stout, flexuose, reddish brown.

Sexual condition

dioicous;

perichaetial leaves somewhat longer than the stem leaves, ending in a slender awn.

dioicous;

perigonia intense wine-red;

perichaetial leaves a little longer than foliage leaves, with hyaline lamina and longer awns.

Capsule

2–3 mm, short-rectangular to almost cubic (1–1.5:1), brownish, sharply 4-angled and prismatic, suberect, becoming horizontal when ripe;

peristome 200–230 µm, divided to 0.8, the teeth 64, obtuse.

2.5–3.5 mm, short to almost cubic (1.5–2:1), inclined, becoming horizontal when mature;

peristome rather short, 110–180(–200) µm, divided to 0.6, the teeth about 64, obtuse.

Calyptra

dirty white to light brown, enclosing the capsule.

dirty white to light brown, enclosing the capsule.

Spores

7–9(–15) µm.

9–12 µm.

Polytrichum strictum

Polytrichum piliferum

Habitat Sphagnum bogs, wet heaths and tundra, muskeg, sedge meadows, moist alpine tundra, also on local elevations and on rotten stumps in wet spruce forests Shallow well-drained sandy or gravelly soil over rocks and boulders in sunny situations, often associated with Cladonia, in road cuts, old fields, burned over areas, heaths, rocky ridges and moraines, and in dry alpine tundra and late snow areas northward
Elevation low to high elevations low to moderate elevations
Distribution
from FNA
AK; CA; CO; CT; GA; IA; IL; IN; MA; MD; ME; MI; MN; MT; NC; NH; NJ; NY; OH; OR; PA; RI; UT; VT; WA; WI; WV; WY; AB; BC; MB; NB; NL; NS; NT; NU; ON; PE; QC; SK; YT; South America; e Asia (Russia, Japan); Atlantic Islands (Faroes, Iceland); Greenland; n Asia; n Europe (Scandinavia, Svalbard); Antarctica
[WildflowerSearch map]
from FNA
AK; AL; AZ; CA; CO; CT; IA; ID; IN; KS; KY; LA; MA; ME; MI; MN; MO; MT; NC; ND; NE; NH; NJ; NM; NY; OH; OR; PA; SD; TN; UT; VA; VT; WA; WI; WV; WY; HI; AB; BC; MB; NB; NL; NS; NT; NU; ON; PE; QC; YT; South America; Australia; Greenland; Atlantic Islands (Falkland Islands, Macaronesia); Asia; Europe; Antarctica
[WildflowerSearch map]
Discussion

Polytrichum strictum is widespread in the boreal regions of the Holarctic, and is one of the commonest low arctic representatives of the family (D. G. Long 1985), with survivals southward in relict bogs, for example in northern Indiana, northern Illinois, and northwestern Iowa, also in alpine situations in the eastern mountains to the Carolinas and Georgia. In Nunavut, it is known from Baffin, Bathurst, and Devon islands. Its characteristic habitat is on hummocks in Sphagnum bogs, in deep masses tightly bound together by dirty-white, wooly tomentum, with short, stiffly erect leaves, and cubical capsules, a clear correlation between a distinctive morphology, distribution, and ecology.

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

Polytrichum piliferum is easily recognized by its habit, growing in short, loose reddish brown clumps, each plant crowned by a whitish tuft of intertwined hyaline awns. The intensely colored, wine-red antheridial rosettes are remarkably flower-like in appearance. The lamella marginal cells are pyriform in section, ending in a distinct knob, except for the lamellae standing in the shade of the inflexed lamina. The leaves of P. piliferum are smooth abaxially and abruptly contracted to the base of the awn; P. juniperinum is a larger plant with reddish rather than hyaline awns; P. hyperboreum is typically fastigiately branched, the leaves with a channeled leaf apex, tapering to a bicolored awn. In Nunavut, it is known from Baffin and Melville islands.

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

Source FNA vol. 27, p. 139. FNA vol. 27, p. 140.
Parent taxa Polytrichaceae > Polytrichum Polytrichaceae > Polytrichum
Sibling taxa
P. commune, P. hyperboreum, P. jensenii, P. juniperinum, P. piliferum, P. swartzii
P. commune, P. hyperboreum, P. jensenii, P. juniperinum, P. strictum, P. swartzii
Synonyms P. affine, P. juniperinum var. affine, P. juniperinum var. gracilius
Name authority Bridel: J. Bot. (Schrader) 1800(1): 286. (1801) Hedwig: Sp. Musc. Frond., 90. (1801)
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