Helianthus tuberosus L.
Species Image Gallery
(opens in a new window)
Family: Asteraceae or Compositae
Genus: Helianthus
Species Synonyms: Helianthus tomentosus Michx.
Helianthus tuberosus var. subcanescens Gray
Common Names: Jerusalem artichoke
Jerusalem sunflower
Canada: southeastern Saskatchewan – Ontario
Saskatchewan: southeastern Saskatchewan; Souris River Valley and Antler River Valley
Ecoregion: Moist Mixed Grassland, Aspen Parkland
Saskatchewan: semi-shaded or wooded river shores
Associated Species: Acer negundo, Bromus inermis, Bromus latiglumis, Elymus virginicus, Galium triflorum, Prunus virginiana, Sonchus arvensis, Stachys palustris, Thalictrum dasycarpum
Provincial Status According
to Harms (2003):
Nature Conservancy Status:
G5 S2
Saskatchewan Species at
Risk Status:
Helianthus tuberosus is highly regionally restricted in the province, occurring only in the southeast corner. These populations represent the northern and western expansion of this species.
Height: 1 – 3 m tall
Roots: fibrous; cigar-shaped, semi-edible tubers on rhizomes
Stems: thick, firm, branched above, hirsute to scabrous, occasionally glabrous
Leaves: cauline, opposite, uppermost alternate, abruptly tapered at base to petiole, 10 – 25 cm long, 6 – 15 cm wide, ovate to broadly lanceolate, 3-nerved for at least half of blade length, veins yellow on underside of leaf, adaxial surface scabrous, abaxial surface puberulent, margin serrate
Inflorescence: heads several, 1 – 2.5 cm broad; peduncles scabrous; phyllaries in 3 series, equal to or slightly exceeding disc, loose or reflexed at maturity, lanceolate, apex acute to acuminate; receptacle low convex, chaff pubescent at apex
Flowers: ligulate florets 5 – 15, 2 – 4 cm long, to 1 cm wide, 3 apical teeth, pistillate, infertile, yellow; tubular florets numerous, perfect, fertile, yellow
Fruits: achenes 5 – 7 mm long, glabrous; pappus two deciduous awns
1 Annuals; taproots; leaves mostly alternate; receptacle flat or nearly so
1 Perennials; tough creeping rhizomes or erect branching crowns; leaves mostly opposite
(upper leaves commonly alternate); receptacle convex or low conical
2 Lower leaves cordate and toothed, pubescence rough; involucral bracts attenuate with conspicuously hairy margins; central chaff not very hairy
H. annuus
2 Lower leaves not cordate, entire; involucral bracts gradually attenuate and not conspicuously hairy; central chaff with white hairs at apex
H. petiolaris ssp. petiolaris
3 Disc flowers dark brown, purple, or red
3 Disk flowers yellow or brown
4 Plants 1 – 2 m tall; leaves in 7 or more pairs; blade ovate to oblanceolate, 8 – 20 cm long, apex long-acuminate
H. pauciflorus ssp. pauciflorus
4 Plants < 1.2 m tall; leaves in 5 – 7 pairs; blade rhombic to lanceolate, 5 – 12 cm long, apex acute to obtuse
H. pauciflorus ssp. subrhomboideus
5 Involucral bracts appressed to the disk, imbricate
H. pauciflorus ssp. pauciflorus
5 Involucral bracts loose-spreading, all about the same length
6 Rootstocks with tubers; leaves ovate to broadly lanceolate, generally 3 times as long as wide
H. tuberosus
6 Rootstocks without tubers; leaves lanceolate to linear lanceolate, generally at least 3 times as long as wide
7 Middle leaves may be folded lengthwise, scabrous above, occasionally below
H. maximiliani
7 Middle leaves always flat, rough hispid to tomentose above, rough hispid to villous-tomentose below
8 Stems 20 – 30 dm tall; upper leaves alternate, lanceolate and acute to acuminate
H. nuttallii ssp. nuttalli
8 Stems 5 – 20 dm tall; upper leaves mostly opposite, lanceolate-ovate, acute to obtuse
H. nuttallii ssp. rydbergii