Ambrosia bidentata Michx.

Cite taxon page as 'WFO (2021): Ambrosia bidentata Michx. Published on the Internet; Accessed on: 26 Oct 2021'

General Information

Annuals, 10–30(–100+) cm. Stems erect. Leaves mostly opposite; petioles 0–0.5 mm; blades ± lanceolate to lance-linear, 15–40+ × 3–6(–10+) mm, bases rounded to cordate, margins entire or with (1–)2(–4) basal lobes, abaxial and adaxial faces ± piloso-hispid and gland-dotted. Pistillate heads clustered, proximal to staminates; florets 1. Staminate heads: peduncles 0–0.5 mm; involucres obliquely cup-shaped (lateral lobe longer than others), 2.5–4 mm diam., piloso-hispid; florets 6–8+. Burs: bodies pyramidal, 5–8 mm, piloso-hispid, spines 4(–5), ± distal, ± acerose, 0.5–1 mm, tips straight.

  • Provided by: [C].Flora of North America @
    • Source: [
    • 1
    • ]. 

    "Branching annual weed 3–10 dm, the stem conspicuously spreading-hirsute, especially above; lvs numerous, sessile, opposite below, alternate above, lanceolate, acuminate, 2.5–7 cm × 4–10 mm, usually with a single pair of sharp large teeth below the middle, hirsute to scabrous, or the upper side glabrous; staminate heads sessile, the invol strongly oblique, its upper side produced into a conspicuous, retrorsely spreading, hispid-hirsute, lanceolate to triangular- ovate lobe, the bractless infl thus appearing retrorse-bracteate; fruiting invol 5–8 mm, villous-hirsute, several-ribbed, the ribs produced into short, stiff spines; 2n=34. Prairies and waste places; O. and Ky. to Nebr., La., and Tex., and occasionally intr. elsewhere. July–Oct."

  • Provided by: [B].New York Botanical Garden
    • Source: [
    • 2
    • ]. 


     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
    World Flora Online consortium
    World Flora Online Data. 2018.
    • D CC0 1.0 Universal (CC0 1.0).