72a. Sphagnum fimbriatum Wilson & Hooker subsp. fimbriatum
Sphagnum bolanderi Warnstorf
Plants typically small and slender; capitulum small and with a conspicuous terminal bud; green to yellowish brown. Stem leaves broad-spatulate, 0.8-1.5(-2) mm, strongly lacerate across the broad apex and partway down the sides, border scarcely to moderately broadened at leaf base (0.25 width of base or less. Sexual condition monoicous. Spores 20-27 µm, finely papillose on both surfaces; proximal laesura less than 0.5 spore radius.
Capsules mature late spring and early summer. Minerotrophic, common at the mineral soil margins of bogs and poor fens, medium open and forested fens; low to high elevations; Alta., B.C., Man., N.B., Nfld. and Labr. (Nfld.), N.S., Ont., Que., Sask.; Alaska, Calif., Colo., Conn., Del., Idaho, Ill., Ind., Iowa, Ky., Maine, Md., Mass., Mich., Minn., Mo., Mont., N.H., N.J., N.Y., Ohio, Oreg., Pa., R.I., Tenn., Vt., Wash., W.Va., Wis.; South America; Eurasia; Pacific Islands (New Zealand).
Sporophytes are very common in subsp. fimbriatum. It is associated with Sphagnum centrale, S. fallax, S. henryense, S. affine, S. palustre, S. russowii, S. teres, S. warnstorfii, and Drepanocladus exannulatus. It is normally very easily recognizable because of its very small size, pale green color, and distinct terminal bud. In Alaska it overlaps with subsp. concinnum, which has a similarly very broad and lacerate stem leaf apex but the lacerate margin does not extend down the sides of the leaf. Subspecies concinnum is also a more compact-growing taxon with a distinctly browner color.