Botrychium sect. Hiemobotrychium
Novon 2: 267. 1992.
Roots 20–30, yellow to brown, 0.6–1 mm diam. 1cm from base. Plants over 6 cm. Common stalk with tracheidal idioblasts. Trophophore short-stalked and prostrate, arising from basal portion of common stalk near ground level; blades usually 2 per plant, appearing in late fall and dying in early spring, deltate, 2–3-pinnate, mostly 5–8 cm wide when mature, herbaceous. Leaf primordia with scattered hairs, hairs 0.6–1 mm. Leaf-sheath closed. Pinna divisions reduced to tip. First pinnule on basal pinnae usually borne basiscopically. Sporophores long-stalked, arising from basal portion of common stalk near ground level, commonly absent without primordia; stalks and rachis broadly flattened, fleshy, to 1.4 mm wide. x =45.
Endemic to se United States
Tracheidal idioblasts in Botrychium sect. Hiemobotrychium are enormous, elongate, spindle-shaped cells with helical or annular thickenings and are scattered along the vascular strand. They are unique among ferns.