4. Botrychium dissectum Sprengel, Anleit. Kenntn. Gew. 3: 172. 1804.
Dissected grapefern, botryche découpé
Botrychium obliquum Muhlenberg in Willdenow
Trophophore stalk 3--15 cm, 1.5--2.5 times length of trophophore rachis; blade shiny green, often bronze in winter, plane to convex, 3--4-pinnate, to 20 × 30cm, leathery. Pinnae to 10 pairs, approximate to remote, slightly ascending, distance between 1st and 2d pinnae not or slightly more than between 2d and 3d pairs, undivided except in proximal 2/3--3/4. Pinnules usually obliquely angular--trowel-shaped to widely trowel-shaped to obliquely round-lanceolate to ovate and pointed, margins denticulate to lacerate to coarsely cut halfway or wholly into linear-divergent segments in some populations, venation pinnate. Sporophores 2--3-pinnate, 1.5--2.5 times length of trophophore. 2 n =90.
Leaves green over winter, new leaves appearing in late spring. In variety of habitats, open grassy areas to deep forest; 0--1500 m; N.B., N.S., Ont., Que.; Ala., Ark., Conn., Del., D.C., Fla., Ga., Ill., Ind., Iowa, Kans., Ky., La., Maine, Md., Mass., Mich., Miss., Mo., N.H., N.J., N.Y., N.C., Ohio, Pa., R.I., S.C., Tenn., Tex., Vt., Va., W.Va., Wis.; West Indies in the Antilles.
Botrychium dissectum is highly variable, even within the same population. In Florida and along the Gulf Coast, the extremely lacerate form is absent, and the blade segments are usually strongly angular, trowel-shaped, and dentate. In eastern Kentucky and central Tennessee in forested valleys, on shale and limestone soils, plants have narrowly linear, somewhat blunt-tipped segments with a more or less whitish gray central line above the veins. This variant, which grows with B . dissectum , may deserve recognition as a distinct species.