Arctium tomentosum Mill.

Cite taxon page as 'WFO (2020): Arctium tomentosum Mill. Published on the Internet; Accessed on: 24 Oct 2020'

General Information

Herbs to 2 m tall, biennial. Stem erect, branched, sparsely cobwebby; branches ascending. Leaves abaxially grayish white and densely felted, adaxially green and glabrous. Basal leaves petiolate; leaf blade heart-shaped, 25-50 × 10-30 cm, margin sparsely denticulate, teeth spinulose or mucronulate, apex acute to obtuse and mucronulate. Cauline leaves similar to basal leaves; uppermost cauline leaves sessile, ovate to ovate-elliptic. Capitula few to many, ± corymbose. Involucre ovoid, 1.5-2 cm in diam., ± densely cobwebby. Outer phyllaries subulate, triangular-subulate, or lanceolate, ca. 6 × 1 mm; middle phyllaries linear-subulate, 10-14 × ca. 2 mm, all with a hooked apex; inner phyllaries lanceolate to linear-lanceolate, apex acuminate. Corolla purplish red, 0.9-1.2 cm, tube 4.5-6 mm. Achene pale brown variegated with dark brown, narrowly obovoid, ca. 5.6 mm, multistriate. Pappus bristles pale brown, ca. 3 mm. Fl. and fr. Jul-Sep.

  • Provided by: [D].Flora Of CHina @
    • Source: [
    • 1
    • ]. 

    Plants to 250 cm. Basal leaves: petioles hollow or solid, 10–15 cm, glandular-hairy; blades 30–40 × 16–28 cm, coarsely dentate to subentire, abaxially white-tomentose, adaxially green, sparsely short-hairy. Heads usually in corymbiform clusters, long-pedunculate. Peduncles 1.5–12 cm. Involucres 15–25 mm diam., densely cobwebby (rarely glabrate). Phyllaries linear to linear-lanceolate, inner usually purplish, margins with minute spreading or reflexed glandular hairs. Florets 30+; corollas rose-purple, (occasionally white), 9–13 mm. limb minutely glandular. Cypselae light brown, 5–8 mm; pappus bristles 1–3 mm. 2n = 36.

  • Provided by: [C].Flora of North America @
    • Source: [
    • 2
    • ]. 

    "Resembling no. 3 [Arctium lappa L.] but smaller, seldom over 13 dm; lower petioles mostly hollow; invol mostly 1.5–2.5 cm thick, ± strongly arachnoid-tomentose and the bracts only weakly or scarcely hooked; cor-limb glandular outside; 2n=36. Native of Eurasia, sparingly established in our range. June–Oct."

  • Provided by: [B].New York Botanical Garden
    • Source: [
    • 3
    • ]. 

     Information From

    CC0 1.0 Universal (CC0 1.0).
    • A CC0 1.0 Universal (CC0 1.0).
    New York Botanical Garden
    Descriptions of plants should be attributed to the full citation for each individual article, chapter or book that is the source for each record, which should include the authors of original publication.
    • B Content licensed under Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License
    Flora of North America @
    'Flora of North America @ eFloras (2008). Published on the Internet [accessed August 2016]' Missouri Botanical Garden, St. Louis, MO & Harvard University Herbaria, Cambridge, MA.
    • C Flora of North America Association
    Flora Of CHina @
    'Flora of China @ eFloras (2008). Published on the Internet [accessed August 2016]' Missouri Botanical Garden, St. Louis, MO & Harvard University Herbaria, Cambridge, MA.
    • D Missouri Botanical Garden
    World Flora Online consortium
    World Flora Online Data. 2018.
    • E CC0 1.0 Universal (CC0 1.0).