Home Flora of Missouri
Home
Name Search
Families
Volumes
!Arctium minus (Hill) Bernh. Search in The Plant ListSearch in IPNISearch in Australian Plant Name IndexSearch in NYBG Virtual HerbariumSearch in Muséum national d'Histoire naturelleSearch in Type Specimen Register of the U.S. National HerbariumSearch in Virtual Herbaria AustriaSearch in JSTOR Plant ScienceSearch in SEINetSearch in African Plants Database at Geneva Botanical GardenAfrican Plants, Senckenberg Photo GallerySearch in Flora do Brasil 2020Search in Reflora - Virtual HerbariumSearch in Living Collections Decrease font Increase font Restore font
 

Published In: Systematisches Verzeichnis 154. 1800. (Syst. Verz.) Name publication detail
 

Project Name Data (Last Modified On 8/11/2017)
Acceptance : Accepted
Project Data     (Last Modified On 7/9/2009)
Status: Introduced

 

Export To PDF Export To Word

1. Arctium minus (Hill) Bernh. (common burdock)

Pl. 250 a–c; Map 1037

Plants coarse, biennial, with stout taproots. Stems 50–180 cm long, erect or ascending, usually branched, stout, longitudinally ridged, not winged, minutely hairy, at least toward the tip, often reddish- or purplish-tinged. Leaves basal and alternate, long-petiolate (petioles of the basal leaves usually hollow), not decurrent, the blades with the margins irregularly wavy or shallowly lobed and often also toothed, the upper surface glabrous or with scattered hairs along the main veins, the undersurface pale-colored, sparsely to moderately pubescent with minute, few-branched hairs (these sometimes appearing cobwebby), sometimes becoming nearly glabrous with age. Basal leaves with the blades 30–60 cm long, narrowly to broadly ovate, more or less cordate at the base, rounded to bluntly or sharply pointed at the tip. Stem leaves progressively smaller toward the tip, ovate to triangular-ovate, shallowly cordate, truncate, or abruptly tapered at the base, rounded to bluntly or sharply pointed at the tip, sometimes abruptly tapered to a short, sharp point. Inflorescences axillary and terminal, the heads sessile or short-stalked, appearing clustered or more commonly in short, dense racemes. Heads discoid, the involucre broadly ovoid to nearly spherical (sometimes appearing bell-shaped when pressed), 1.2–2.5 cm in diameter, the florets all appearing similar and perfect. Receptacle flat, with numerous bristles. Involucral bracts 4–13 mm long, the body narrowly lanceolate, appressed-ascending, glabrous or somewhat glandular, occasionally cobwebby-hairy, tapered to a long, stiff, ascending bristle, this hooked at the tip (the innermost bracts often with somewhat flattened, hookless bristles). Pappus of several unequal series of short, flattened, bristlelike awns, these 1–3 mm long, with short, ascending barbs, mostly shed individually by fruiting. Corollas 7–9 mm long, pink to purple, often somewhat glandular. Fruits appearing basally attached, 4–6 mm long, oblong or slightly narrower at the symmetrical base, somewhat flattened, the surface finely wrinkled, grayish brown with darker mottling. 2n=32, 36. July–October.

Introduced, scattered sporadically nearly throughout the state (native of Europe, Asia, introduced widely in North America). Rarely disturbed openings of mesic upland forests and banks of streams; more commonly barnyards, feedlots, old fields, pastures, railroads, and open, disturbed areas.

Young stems of burdock are eaten fresh or more commonly baked or boiled. The young herbage sometimes also is eaten by livestock. The thick roots can be cooked and eaten, and in the past they sometimes were dried and ground for use as a filler in coffee. They also have been used medicinally as a laxative, diuretic, to lessen the symptoms of rheumatism, and in a paste to treat burns and sores (Steyermark, 1963). The burlike heads are dispersed mostly in animal fur, and the individual fruits are shed from the head very tardily.

Most plants have pink to light reddish purple corollas. Rare individuals with darker purple corollas have been called f. purpureum (Blytt) A.H. Evans, and white-flowered plants are known as f. pallidum Farw.

Steyermark (1963) treated A. tomentosum Mill. (cotton burdock) based on historical collections from Jackson County. However, Mühlenbach (1983) concluded that all of these specimens were misdetermined plants of A. minus. Arctium tomentosum is another Eurasian species that is weedy in the New World. It differs from A. minus in its shorter, more flat-topped inflorescences with mostly long-stalked, generally slightly larger heads, and corollas that are usually somewhat glandular on the outer surface (Moore and Frankton, 1974). The few Missouri specimens in question do have longer stalks, but the heads otherwise resemble those of A. minus, and the inflorescences overall are elongate rather than flat-topped.

 


 

 
 
© 2024 Missouri Botanical Garden - 4344 Shaw Boulevard - Saint Louis, Missouri 63110