Leaves monomorphic, green through winter, 25--90 × 8--30 cm. Petiole 1/4--1/3 length of leaf, scaly at least at base; scales scattered, light brown. Blade green to yellow-green, ovate-lanceolate, pinnate-pinnatifid to 2-pinnate at base, herbaceous, glandular. Pinnae ± in plane of blade, lance-oblong; basal pinnae deltate, not much reduced, basal pinnules ± same length as adjacent pinnules, basal basiscopic pinnule and basal acroscopic pinnule ± equal, pinnule margins serrate with spreading, spinelike teeth. Sori midway between midvein and margin of segments. Indusia lacking glands. 2 n = 82. Shaded slopes and open woods; 0--2100 m; B.C.; Ariz., Calif., Oreg., Wash.; Mexico in Baja California. Dryopteris arguta is somewhat variable. It has been suggested that more than one taxon is involved. No hybrids involving D . arguta are known.