ABSTRACT
Cultivated in many regions of Siberia, sometimes grows wildly. Culti vated in many regions of the world. Originated from Nor. America.
2. H. tuberosus L. 1753, Sp. Pl.: 905. Plant up to 2 m tall. Stem puberulent. Leaves with short stiff pubescence
on upper surface, pubescent more compactly and soft-haired beneath; lower cauline leaves petiolate, cordate-ovate margin large-serratodentate; upper leaves oblong-ovate or lanceolate. Anthodia 2-8 cm in diam., rarely some what larger, upright. Bracts of involucre lanceolate, hairy. Ray flowers ligulate, sterile, golden yellow; disc flowers tubular, yellow, bisexual, fertile. Achenes cuneate, puberulent. Outside Siberia, 2 n = 102.
