Distribution: Occurring in scattered locations chiefly east of the Cascades crest in Washington; .Washington, east to the Rocky Mountains, native from the Great Plains to the Atlantic Coast.
Habitat: Roadsides, fields, ditches, wastelots, and other disturbed areas, where escaping from cultivation.
Flowers: August-October
Origin: Introduced from central and eastern North America
Growth Duration: Perennial
Conservation Status: Not of concern
Pollination: Bumblebees, bees, butterflies, wasps
Perennial with tuber-bearing rhizomes, the stem stout, pubescent, 0.7-5 m. tall.
Leaves opposite below and alternate above, broadly lanceolate to ovate, acuminate, 10-25 cm. long and 4-12 cm. wide, with winged petioles 2-8 cm. long, the blades serrate, scabrous above.
Heads usually numerous, the disk 1.5-2.5 cm. wide, the receptacle chaffy; involucre bracts dark, narrowly lanceolate, acuminate, exceeding the disk, scabrous on the back; disk flowers yellow, perfect; ray flowers 10-20, yellow, neutral, 2-4 cm. long; pappus of 2 deciduous awns.
Achenes thick, compressed.
PNW Herbaria: Specimen records of Helianthus tuberosus in the Consortium of Pacific Northwest Herbaria database.
WA Flora Checklist: Helianthus tuberosus checklist entry.
OregonFlora: Helianthus tuberosus information.
E-Flora BC: Helianthus tuberosus atlas page.
CalPhotos: Helianthus tuberosus photos.
USDA Plants: Helianthus tuberosus information.