Arctium minus is a complex species with many variants that have been recognized at ranks ranging from forma to species (J. Arènes 1950). Some North American workers (e.g., R. J. Moore and C. Frankton 1974) have often distinguished plants with involucres more than 3 cm diameter that equal or overtop the corollas as A. nemorosum. Arènes treated those plants as a subspecies of A. minus. Arctium nemorosum was recognized as a species distinct from A. minus (H. Duistermaat 1996), with a different and more restricted circumscription than that used by North American workers. Although most of the characters that Duistermaat used to separate those A. nemorosum from A. minus overlap extensively, the consistently wider mid phyllaries of A. nemorosum (1.7–2.5 mm wide versus 0.6–1.6 mm in A. minus) supposedly distinguish the species. None of the North American specimens examined in preparation of this treatment had the wide phyllaries of A. nemorosum in the sense of Duistermaat, who stated that she had seen no material of this taxon from the American continent. Some American authors have taken up the name Arctium vulgare in place of A. nemorosum and applied A. vulgare (dubbed woodland burdock) to the larger-headed North American plants. Duistermaat considers A. vulgare to be a synonym of A. lappa.
Arctium minus, commonly known as lesser burdock,[2] little burdock, louse-bur, common burdock,[3] button-bur, cuckoo-button,[3] or wild rhubarb,[4] is a biennial plant. This plant is native to Europe,[5] but has become introduced elsewhere such as Australia, North and South America, and other places.[6][7][8][9]
Lesser burdock produces purple flowers in its second year of growth, from July to October. Outer bracts end in hooks that are like hook-and-loop. After the flower head dries, the hooked bracts will attach to humans and animals to transport the entire seedhead.[10]
Arctium minus can grow up to 1.8 metres (5 ft 11 in) tall[11] and form multiple branches. It is large and bushy. Flowers are prickly and pink to lavender in color. Flower heads are about 2 cm (0.79 in) wide.[11] The plant flowers from July through October. The flowers resemble and can be easily mistaken for thistles, but burdock can be distinguished by its extremely large (up to 50 cm) leaves and its hooked bracts. Leaves are long and ovate. Lower leaves are heart-shaped and have very wavy margins. Leaves are dark green above and woolly below. It grows an extremely deep taproot, up to 30 cm (12 in) into the ground.[12][13]
The leafstalks (a year old or younger) and flower stalks can be eaten raw or cooked. The roots are edible boiled with a change of water,[11] though become too woody to eat in plants over a year old.[14]
Arctium minus, commonly known as lesser burdock, little burdock, louse-bur, common burdock, button-bur, cuckoo-button, or wild rhubarb, is a biennial plant. This plant is native to Europe, but has become introduced elsewhere such as Australia, North and South America, and other places.
Lesser burdock produces purple flowers in its second year of growth, from July to October. Outer bracts end in hooks that are like hook-and-loop. After the flower head dries, the hooked bracts will attach to humans and animals to transport the entire seedhead.
