Leaves monomorphic, green through winter, 30--100 × 10--25 cm. Petiole 1/4--1/3 length of leaf, scaly at base; scales in dense tuft, pale tawny. Blade bluish green, ovate-lanceolate, pinnate-pinnatifid to 2-pinnate at base, leathery, not glandular. Pinnae ± in plane of blade, lanceolate; basal pinnae lanceolate, slightly reduced, basal pinnules longer than adjacent pinnules, basal basiscopic pinnule longer than basal acroscopic pinnule; pinnule margins shallowly crenate to nearly entire. Sori near margin of segments. Indusia lacking glands. 2 n = 82. Rocky, wooded slopes and ravines, edges of woods, stream banks and roadbanks, and rock walls; 50--1500 m; Greenland; N.B., Nfld, N.S., Ont., Que.; Ala., Ark., Conn., Del., Ga., Ill., Ind., Iowa, Kans., Ky., Maine, Md., Mass., Mich., Miss., Mo., N.H., N.J., N.Y., N.C., Ohio, Okla., Pa., R.I., S.C., Tenn., Vt., Va., W.Va., Wis. Dryopteris marginalis is an eastern North America endemic. Even though this species hybridizes with 10 other species, and some of these hybrids are fairly common, D . marginalis is not known to be involved in the formation of any fertile polyploid. Hybrids can be detected by malformed spores and the nearly marginal sorus position.
Rhizome ascending to erect; lvs firm, evergreen; petiole 1-2 dm, with a tuft of slender, concolorous, pale reddish-brown scales at the base and smaller, scattered scales above; blade lance-oblong, (2-)3-4.5 נ1-2.5 dm, broadest just above the base, glabrous but with a few hair-like scales, pinnate-pinnatifid to bipinnate, with 15-20 pairs of pinnae, the larger pinnae with mostly 10-15(-18) pairs of segments, the larger segments mostly (0.7-)1-2(-2.5) cm, with 6-9 pairs of veins; sori submarginal, near the sinuses between the teeth; 2n=82. Woods and talus-slopes; Nf. to S.C. and Ga., w. to s. Ont., Minn., Kans., and Okla.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.