Plants of the genus Arctium have dark green leaves that can grow up to 18" (45 cm) long. They are generally large, coarse and ovate, with the lower ones being heart-shaped. They are woolly underneath. The leafstalks are generally hollow. Arctium species generally flower from July through October.
The prickly heads of these Old World plants are noted for easily catching on to fur and clothing, thus providing an excellent mechanism for seed dispersal. Burrs cause local irritation and can possibly cause intestinal hairballs in pets. However, most animals avoid ingesting these plants.
A large number of species have been placed in genus Arctium at one time or another, but most of them are now classified in the related genus Cousinia. The precise limits between Arctium and Cousinia are hard to define; there is an exact correlation between their molecular phylogeny. The burdocks are sometimes confused with the cockleburs (genus Xanthium) and rhubarb (genus Rheum).
The roots of burdock, among other plants, are eaten by the larva of the Ghost Moth (Hepialus humuli). The plant is used as a food plant by other Lepidoptera including Brown-tail, Coleophora paripennella, Coleophora peribenanderi, The Gothic, Lime-speck Pug and Scalloped Hazel.
Food and drink
The taproot of young burdock plants can be harvested and eaten as a root vegetable. While generally out of favor in modern European cuisine, it remains popular in Asia, particularly in Japan where A. lappa (Greater burdock) is called gobō (牛蒡 or ゴボウ). Plants are cultivated for their slender roots, which can grow about 1 meter long and 2 cm across. Burdock root is very crisp and has a sweet, mild, and pungent flavor with a little muddy harshness that can be reduced by soaking julienne/shredded roots in water for five to ten minutes. Immature flower stalks may also be harvested in late spring, before flowers appear; the taste resembles that of artichoke, to which the burdock is related. A popular Japanese dish is kinpira gobō, julienned or shredded burdock root and carrot, braised with soy sauce, sugar, mirin and/or sake, and sesame oil; another is burdock makizushi (sushi filled with pickled burdock root rather than fish; the burdock root is often artificially colored orange to resemble a carrot). In the second half of the 20th century, burdock achieved international recognition for its culinary use due to the increasing popularity of the macrobiotic diet, which advocates its consumption. It also contains a fair amount of gobō dietary fiber (GDF, 6g per 100g), calcium, potassium, amino acids, and is also low calorie. It also contains polyphenols that causes darkened surface and muddy harshness by formation of tannin-iron complexes though the harshness shows excellent harmonization with pork in miso soup (tonjiru) and Japanese-style pilaf (takikomi gohan).
Folk herbalists consider dried burdock to be a diuretic, diaphoretic, and a blood purifying agent. The seeds of A. lappa are used in traditional Chinese medicine, under the name niupangzi (Template:Zh-cp; Some dictionaries list the Chinese as just 牛蒡 niúbàng.)
Burdock is a traditional medicinal herb that is used for many ailments. Burdock root oil extract, also called Bur oil, is popular in Europe as a scalp treatment applied to improve hair strength, shine and body, help reverse scalp conditions such as dandruff, and combat hair loss. Modern studies indicate that Burdock root oil extract is rich in phytosterols and essential fatty acids (including rare long-chain EFAs), the nutrients required to maintain a healthy scalp and promote natural hair growth. It combines an immediate relieving effect with nutritional support of normal functions of sebaceous glands and hair follicles.
According to some European herbalists, combining Burdock root oil with a Nettle root oil and massaging these two oils into the scalp every day has a greater effect than Bur oil alone.
Burdock and Velcro
After taking his dog for a walk one day in the early 1940s, George de Mestral, a Swiss inventor, became curious about the seeds of the burdock plant that had attached themselves to his clothes and to the dog's fur. Under a microscope, he looked closely at the hook-and-loop system that the seeds use to hitchhike on passing animals aiding seed dispersal, and he realised that the same approach could be used to join other things together. The result was Velcro.
The Russian writer, Leo Tolstoy, wrote in his journal, 1896, about a tiny shoot of burdock he saw in a ploughed field, “black from dust but still alive and red in the center … It makes me want to write. It asserts life to the end, and alone in the midst of the whole field, somehow or other had asserted it.”
- Arctium lappa : Greater Burdock, Gobō
- Arctium minus : Lesser Burdock, Burweed, Louse-bur, Button-bur
- Arctium minus nemorosum (=Arctium vulgare) : Woodland Burdock, Wood Burdock
- Arctium pubens : Common Burdock
- Arctium tomentosum : Downy Burdock, Woolly Burdock
Because the roots of burdock closely resemble those of Deadly nightshade (also known as belladonna or Atropa belladonna), there is a risk that burdock preparations may be contaminated with these potentially dangerous herbs. Be sure to buy products from established companies with good reputations. Do not gather burdock in the wild unless you know what you are doing.