Osmunda multifida S.G. Gmelin, Novi Comment. Acad. Sci. Imp. Petrop. 12: 517. 1768; Botrychium californicum L.Underwood; B. coulteri L.Underwood; B. silaifolium C.Presl
Trophophore stalk 2--15 cm, 0.3--1.2 times length of trophophore rachis; blade shiny green, plane, ternate, 2--3-pinnate, to 25 × 35 cm, leathery. Pinnae to 10 pairs, approximate to remote, horizontal to ascending, distance between 1st and 2d pinnae not or slightly more than between 2d and 3d pairs, divided to tip. Pinnules obliquely ovate, rounded, margins usually ± entire to shallowly crenulate, sometimes inconspicuously and shallowly denticulate, apex rounded, venation pinnate. Sporophores 2--3-pinnate, 1.2 times length of trophophore. 2 n =90.
Leaves green over winter, appearing in spring. Widespread mainly in fields; 0--3000 m; Greenland; Alta., B.C., Man., N.B., Nfld., N.W.T., N.S., Ont., Que., Sask.; Alaska, Ariz., Calif., Colo., Conn., Idaho, Ill., Ind., Iowa, Maine, Mass., Mich., Minn., Mont., Nev., N.H., N.J., N.Y., N.Dak., Ohio, Oreg., Pa., R.I., S.Dak., Utah, Vt., Va., Wash., W.Va., Wis., Wyo.; Europe; nw Asia.
Botrychium multifidum is rather similar to B . robustum (Ruprecht) L.Underwood of Japan, eastern China, and the former Soviet republics. Specimens identified as B . robustum have been collected on Unalaska Island.
