Lycopodium alpinum L.

Much like no. 13 [Lycopodium stitchense Rupr.], but the lvs of the ultimate vegetative branchlets strictly 4-ranked, decussately opposite, subtrimorphic; every other pair of lvs conspicuously decurrent on the stem as a pair of flanges, the flange continuous with one margin of the lf, so that the stem appears somewhat flattened or wing-margined with the lvs of the lateral rows twisted; free tips of these lateral lvs mostly 1.5–2 mm; dorsal and ventral lvs distinctly different from the lateral ones and also different inter se, those of the upper side subulate, straight, loosely appressed or closely ascending, 2–3 mm, shortly decurrent, those of the lower side (which appears to be concave because of the way the lateral lvs are twisted) tending to have a short, stout, ascending-spreading subpetiolar base (this often laterally compressed) and an erect (parallel to the stem) or incurved blade 2–3 mm and lanceolate or lance-ovate; 2n=46. Cold woods and subalpine meadows and rocky slopes; circumboreal, s. to Keweenaw Co., Mich. and the Gaspé penins. of Que.