Schrader, Index Seminum (Göttingen). 1834: unpaged. 1835.
Maximilian sunflower , hélianthe de Maximilien
, 50—300 cm (rhi-zomatous).
erect, 5—30 dm, scabrous to scabro-hispidulous.
cauline; mostly alternate; petioles 0—2 cm; blades (light green to gray-green, 1-nerved, conduplicate) lanceolate, 10—30 × 2—5.5 cm, bases cuneate, margins usually entire, sometimes serrulate, abaxial faces scabrous to scabro-hispid, gland-dotted.
(1—)3—15 (often in racemiform to spiciform arrays
hemispheric, 13—28 mm diam.
30—40, lanceolate, 14—20 × 2—3 mm, (margins ciliate) apices acute to attenuate, abaxial faces canescent, gland-dotted.
7—11 mm, entire or 3-toothed (apices greenish, mucronate, hairy).
10—25; laminae (15—)25—40 mm.
75+; corollas 5—7 mm, lobes yellow; anthers dark brown or black; appendages usually yellow , sometimes partly dark
3—4 mm, glabrate;
of 2 aristate scales 3—4.1 mm.
Flowering late summer—fall. Prairies , fields, waste areas; 0—300(—2100+) m; Alta., B.C., Man., Ont., Que., Sask.; Ala., Ark., Calif., Colo., Conn., Del., D.C., Idaho, Ill., Ind., Iowa, Kans., Ky., Maine, Md., Mass., Mich., Minn., Miss., Mo., Nebr., N.J., N.Y., N.C., N.Dak., Ohio, Okla., Pa., S.C., S.Dak., Tenn., Tex., Utah, Va., Wash., W.Va., Wis., Wyo.; Mexico.
is introduced in eastern Ontario and in Quebec. It appears to be native to midcontinental prairie regions and has spread along railroads and highways into all areas of North America. Its wide dispersal may be aided by cultivation for its attractive, showy floral displays. In addition to the usually conduplicate, single-nerved leaves and spikelike arrangement of the heads, it is distinguished by the whitish-canescent indument of the leaves and stems and the long-attenuate phyllaries.