provided by North American Flora
Aruncus acuminatus (Dougl.) Rydberg, sp. nov
spiraea Aruncus Hook. Fl. Bor. Am. 1 : 173. 1832. Not 5. Aruncus Iv. 1753. Spiraea acuminata Dougl.; Hook. loc. cit. as a synonym.
Stem 1-2 m. high, glabrous; lower leaves thrice compound, first ternate; the lower divisions usually pinnate with 5 leaflets, and the terminal again ternate ; the lower divisions of this with 3 and the terminal one pinnate with 5 leaflets ; leaflets 3-12 cm. long, lanceolate, long-acuminate at the apex, acute, truncate or subcordate at the base, sharply and doubly serrate, thin, more or less hairy on both sides, especially along the veins, or sometimes glabrous ; the upper leaves less compound and sometimes pinnately 5-foliolate ; panicles terminal and axillary, 1-4 dm. long, that of the staminate plant often more leafy and with shorter branches ; branches 3-15 cm, long, in fruit very lax ; petals of the staminate flowers broadly rounded-obovate, about 1 mm. long and | as broad; those of the pistillate flowers slightly smaller, elliptic ; follicles about 3 mm. long and 1 mm. thick,
Type locality : Mouth of the Columbia.
Distribution : Moist woods and along streams, from northern Oregon to Alaska, and inland to the Selkirk Mountains of British Columbia.
- bibliographic citation
- Frederick Vernon Coville, Nathaniel Lord Britton, Henry Allan Gleason, John Kunkel Small, Charles Louis Pollard, Per Axel Rydberg. 1908. GROSSULARIACEAE, PLATANACEAE, CROSSOSOMATACEAE, CONNARACEAE, CALYCANTHACEAE, and ROSACEAE (pars). North American flora. vol 22(3). New York Botanical Garden, New York, NY