A small relative of Queen Anne’s Lace, this one grows in the woods and bears its few-flowered umbels in spring. This plant was growing along the Trillium Trail, Fox Chapel, where it was blooming in the middle of May. The fern-like leaves are distinctive. A similar species, O. longistylis, is not hairy, and thus easy to distinguish.
Gray describes the genus and the species (which he spells Claytoni):
OSMORHÏZA Raf. SWEET CICELY. Calyx-teeth obsolete. Fruit with prominent caudate attenuation at base, and equal ribs. — Glabrous to hirsute perennials with thick aromatic roots, ternately compound leaves, ovate variously toothed leaflets, few-leaved in volucres, and white flowers in few-rayed and few-fruited umbels. (Name from osme, a scent, and rhiza, a root.) Washingtonia Raf.
O. Claytoni (Michx.) Clarke. Stems rather slender, 8-9 dm. high, vinous-pubescent; leaves <2-3-ternate, crisp-hairy; leaflets mostly 4-7 cm. long, acuminate, crenate-dentate and somewhat cleft; stipules ciliate-hispid; fruit (not including the attenuate base) 1-1.8 cm. long; stylopodium and style 0.7-1 mm. long. (O. brevistylis DC; Washingtonia Claytoni Britton.) — Open woods, e. Que. to w. Ont., s. to N. С, Ala., Mo., and Kan.