Northern beech fern, narrow beech fern, phégoptère à segments joint, fougère du hêtre

Polypodium connectile Michaux, Fl. Bor.-Amer. 2: 271. 1803; Dryopteris phegopteris (Linnaeus) C. Christensen; Phegopteris polypodioides Fée; Polypodium phegopteris Linnaeus; Thelypteris phegopteris (Linnaeus) Slosson

Stems long-creeping, 1--2(--3) mm diam. Leaves monomorphic, dying back in winter, often 1--2 cm apart, 15--60 cm. Petiole straw-colored, (8--)15--36 cm × 1--3 mm, at base with scales brownish, lanceolate, glabrous or sparingly hairy on margin. Blade narrowly to broadly deltate, usually somewhat longer than broad, (6--)12--25 cm, proximal pinnae longest and slightly narrowed at base, spreading or reflexed. Pinnae deeply pinnatifid, (3--)6--12 × 1--3.3 cm, lowermost 1--2 pairs separate, sessile, more distal pairs strongly adnate and connected by narrow rachis wing; segments entire, or those of proximal pinna pair sometimes crenate, uncommonly shallowly lobed; proximal pair of veins from adjacent segments meeting margin above sinus, veins simple or sometimes forked in lowermost pinnae. Indument abaxially of moderately to densely set hairs 0.3--1 mm along costae, veins, and blade tissue, costae also with scales light tan to shiny brown, ovate-lanceolate, spreading, to ca. 3 mm, scales sometimes sparingly hairy on margin. Sori subterminal on veins. n = 2 n = 90, apogamous.

In moist, strongly to moderately acid soil, or on rocks in shaded rock crevices; 0--2200 m; Greenland; St. Pierre and Miquelon; Alta., B.C., Man., N.B., Nfld., N.W.T., N.S., Ont., P.E.I., Que., Sask., Yukon; Alaska, Conn., Del., Idaho, Ill., Ind., Iowa, Maine, Md., Mass., Mich., Minn., Mo., Mont., N.H., N.J., N.Y., N.C., Ohio, Oreg., Pa., R.I., Tenn., Vt., Va., Wash., W.Va., Wis.; Eurasia.