1.
Arctium lappa
Linnaeus, Sp. Pl. 2: 816. 1753.
Great burdock, grande bardane
Plants
to 100—300 cm.
Basal leaves:
petioles solid, 15—36 cm, glabrous or thinly cobwebby; blades 25—80 × 20—70 cm, coarsely dentate to subentire, abaxially thinly gray-tomentose, adaxially green, sparsely short-hairy to nearly glabrous.
Heads
usually in corymbiform clusters, long-pedunculate.
Peduncles
2.5—6 cm.
Involucres
25—45 mm diam.
Phyllaries
linear to linear-lanceolate, glabrous to loosely cobwebby, inner usually stramineous (sometimes purplish), margins with minute spreading or reflexed hairs.
Florets
40+; corollas purple (occasionally white), 9—14 mm, glabrous.
Cypselae
light brown, often with darker spots, 6—7.5 mm;
pappus
bristles 2—5 mm.
2
n
= 32 (Japan), 34 (China), 36 (Japan); (Sweden).
Flowering summer—early fall (Jul—Oct). Waste places, roadsides, fields, forest clearings; 0—2200 m; introduced; Alta., B.C., Man., N.B., Ont., Que., Sask.; Ala., Ariz., Calif., Colo., Conn., Ill., Maine, Mass., Mich., Minn., Nev., N.H., N.Y., N.Dak., Pa., R.I., Utah, Vt., Wash., Wis.; Eurasia.
BONAP lists Georgia, Idaho, Indiana, Iowa, Maryland, Montana, New Jersey, North Carolina, Ohio, Oregon, and Wyoming; I have not seen specimens.
Roots and young leaves of
Arctium
lappa
are edible and can be used in a variety of food preparations. Extracts of
Arctium
species purportedly have health benefits and are sold as food supplements. This species is sometimes cultivated as a minor crop.
