Arctium tomentosum
Arctium lappa
bardane tomenteuse, cotton burdock, woolly burdock, woolly burrdock
grande bardane, great burdock, greater burdock
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.
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.
1.5–12 cm.
2.5–6 cm.
15–25 mm diam., densely cobwebby (rarely glabrate).
25–45 mm diam.
30+;
corollas rose-purple, (occasionally white), 9–13 mm, limb minutely glandular.
40+;
corollas purple (occasionally white), 9–14 mm, glabrous.
linear to linear-lanceolate, inner usually purplish, margins with minute spreading or reflexed glandular hairs.
linear to linear-lanceolate, glabrous to loosely cobwebby, inner usually stramineous (sometimes purplish), margins with minute spreading or reflexed hairs.
usually in corymbiform clusters, long-pedunculate.
usually in corymbiform clusters, long-pedunculate.
light brown, 5–8 mm;
pappus bristles 1–3 mm.
light brown, often with darker spots, 6–7.5 mm;
pappus bristles 2–5 mm.
= 36.
= 32 (Japan), 34 (China), 36 (Japan); (Sweden).
Arctium tomentosum
Arctium lappa
Arctium tomentosum has been reported from Illinois, Iowa, Maryland, New Jersey, Oregon, Pennsylvania, South Carolina, and Wisconsin; I have not seen specimens.The involucres of Arctium tomentosum are usually very densely cobwebby.
Exceptional forms of A. tomentosum have nearly glabrous involucres. Forms of A. minus with especially cobwebby involucres have been misidentified as A. tomentosum; they lack the corymbiform capitulescence and glandular corollas of the latter.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
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.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
MO Plants- Local floras:
BC, 
CA, 
OR, 
WA - Local Web sites: CalFlora, CalPhotos,
Flora NW, 
Go Botany, 
IL Wildflowers, 
MI Flora, 
MN Wildflowers, 
PNW Herbaria 
WildflowerSearch
iNaturalist (observations)
USDA Plants Database- LBJ Wildflower Center
- SEINet
- Plants of the World Online
- Encyclopedia of Life
- Wikipedia
- Google Image Search
