Lactuca canadensis L.
  • "C. von Linnaeus, Sp. Pl.. 1753"
  • Almeirão-serralha

Cite taxon page as 'WFO (2023): Lactuca canadensis L. Published on the Internet; Accessed on: 24 Mar 2023'

General Information

Biennials, (15–)40–200(–450+) cm. Leaves on proximal 1/2–3/4 of each stem; blades of undivided cauline leaves oblong, obovate, or lanceolate to spatulate or lance-linear, margins entire or denticulate, midribs sometimes sparsely pilose. Heads in ± corymbiform to paniculiform arrays. Involucres 10–12+ mm. Phyllaries usually reflexed in fruit. Florets 15–20+; corollas bluish or yellowish, usually deliquescent. Cypselae: bodies brown (often mottled), ± flattened, elliptic, 2.5–3.5 mm, beaks ± filiform, 1–3 mm, faces 1(–3)-nerved; pappi white, 5–6 mm. 2n = 34.

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

    Leafy-stemmed annual or usually biennial 3–25 dm, glabrous or occasionally coarsely hirsute, often ± glaucous; lvs highly variable, entire or toothed to pinnately lobed or cleft, sagittate or sometimes narrowed to the base, 10–35 × 1.5–12 cm; heads numerous, small, with 13–22 yellow fls; invol 10–15 mm in fr; achenes blackish, very flat, with a median nerve on each face, transversely rugulose, 4.5–6.5 mm overall, the slender beak from a little more than half to about as long as the body; mature pappus 5–7 mm; 2n=34. Fields, waste places, and woods; Que. and P.E.I. to Sask., s. to Fla. and Tex. July–Sept. (L. sagittifolia; L. steelei)

  • Provided by: [C].Manual of Vascular Plants of Northeastern US and Canada
    • Source: [
    • 3
    • ]. 


    Caule: cor do látex laranja/amarelado. Folha: lâmina(s) lobada(s); projeção espinescente(s) ausente(s). Flor: cor da antera(s) amarela; cor da corola amarelo escuro. Fruto: ala(s) presente(s); cor do fruto(s) castanha; rostro presente(s).

  • Provided by: [B].Brazilian Flora 2020 project - Projeto Flora do Brasil 2020
    • Source: [
    • 1
    • ]. 

    Tallo: color del latex naranja/amarillento. Hoja: lámina(s) lobada(s); proyeccion espinescente(s) ausente(s). Flor: color de la antera(s) amarilla; color de la corola amarillo escuro. Fruto: ala(s) presente(s); color del fruto(s) marron; rostro presente(s).

  • Provided by: [B].Brazilian Flora 2020 project - Projeto Flora do Brasil 2020
    • Source: [
    • 1
    • ]. 

    Stem: colour of the latex orange/yellowish. Leaf: blade lobate; projection spinescent absent. Flower: colour of the anther yellow; colour of the corolla yellow dark. Fruit: wing present; colour of the fruit brown; rostrum present.

  • Provided by: [B].Brazilian Flora 2020 project - Projeto Flora do Brasil 2020
    • Source: [
    • 1
    • ]. 

    Distribution Map

    • Introduced distribution
    Introduced into
    • Southern America Brazil Paraní
    • São Paulo

    Other Local Names


     Information From

    Asteraceae. The daisy family. World Flora Online Data. 2022.
    • A CC0 1.0 Universal (CC0 1.0).
    Brazilian Flora 2020 project - Projeto Flora do Brasil 2020
    The Brazilian Flora Group (2018): Brazilian Flora 2020. Dataset/Checklist:
    • B Group Brazil Flora, REFLORA Program
    Manual of Vascular Plants of Northeastern US and Canada
    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.
    • C 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.
    • D Flora of North America Association
    World Flora Online Consortium
    World Flora Online Data. 2017.
    • E CC0 1.0 Universal (CC0 1.0).