Trophophore stalk 4--20 cm, 2--2.5 times length of trophophore rachis; blade green to dark green, plane, 2--3-pinnate, to 18 × 28 cm, herbaceous. Pinnae to 7 pairs, usually remote, horizontal, distance between 1st and 2d pinnae not or slightly more than between 2d and 3d pairs, undivided except in proximal 2/3--1/2. Pinnules elongate, obliquely lanceolate to narrowly lanceolate, margins nearly parallel and finely denticulate, apex short-acuminate, venation pinnate. Sporophores 1--2-pinnate, 2--3 times length of trophophore. 2 n =90.
Leaves green over winter, sporophores seasonal, new leaves appearing in late spring--early summer. Frequent in low woods and brushy fields; 0--600 m; Ala., Ark., Del., Fla., Ga., Ill., Ind., Ky., La., Md., Miss., Mo., N.J., N.C., Ohio, Okla., Pa., S.C., Tenn., Tex., Va., W.Va.
Botrychium biternatum often grows with B . dissectum and B . jenmanii . The name B . biternatum was misapplied by L.Underwood to B . lunarioides (W.H. Wagner Jr. 1961).
Blade not strongly dissected, mostly bipinnate, the terminal segment of the principal divisions tending to be more elongate and less divided than the other segments; major lateral segments tending to be oblong; ultimate segments ±cuneate at base; otherwise much like the less-dissected forms of no. 8 [Botrychium dissectum Spreng.]. 2n=90. Woods, swamps, and old fields; se. U.S., n. to Md., Ind., and Mo. Sept.-Nov. (B. dissectum var. tenuifolium)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.