Sp. Pl. 2: 1095. 1753.
Stems short-creeping; scales bronzy deep yellow, concolored, margins entire. Leaves lax-arching (rarely pendent), closely spaced, 40–75 cm. Petiole 1–2 mm diam., glabrous, occasionally glaucous. Blade fan-shaped, pseudopedate, 1-pinnate distally, 15–30 × 15–35 cm, glabrous; proximal pinnae 3–9-pinnate; rachis straight, glabrous, occasionally glaucous. Segment stalks 0.5–1.5(–1.7) mm, dark color entering into segment base. Ultimate segments oblong, ca. 3 times as long as broad; basiscopic margin straight; acroscopic margin lobed, lobes separated by narrow incisions 0–0.9(–1.1) mm wide; apex obtuse, divided into shallow, rounded lobes separated by shallow sinuses 0.1–2(–3.7) mm deep, margins of lobes crenulate or crenate-denticulate. Indusia transversely oblong, 1–3 mm, glabrous. Spores mostly 34–40 µm diam. 2n = 58.
Phenology: Sporulating summer–fall.
Habitat: Rich, deciduous woodlands, often on humus-covered talus slopes and moist lime soils
Elevation: 0–700 m
N.B., N.S., Ont., Que., Ala., Ark., Conn., Del., D.C., Ga., Ill., Ind., Iowa, Kans., Ky., La., Maine, Md., Mass., Mich., Minn., Miss., Mo., Nebr., N.H., N.J., N.Y., N.C., Ohio, Okla., Pa., R.I., S.C., Tenn., Vt., Va., W.Va., Wis.
Once considered a single species across its range in North America and eastern Asia, Adiantum pedatum is considered to be a complex of at least three vicariant species (A. pedatum and A. aleuticum occur in North America) and a derivative allopolyploid species (C. A. Paris 1991). Adiantum pedatum in the strict sense is restricted to deciduous woodlands in eastern North America.