A hardy perennial, 20-30 cm (8-12 in) in height, it has a thick, knotted, yellow rhizome, palmate, deeply lobed leaves, and single greenish-white flowers, with no petals, in late spring to early summer. Fruits are red and raspberry-like, but inedible.
History and traditions
This was once a very common herb in North America, its orange root being variously used to make a yellow dye, in medicinal remedies for digestive problems, bruises and swellings and also as an insect repellent. Early settlers were impressed by its properties and it was listed in the United States Pharmacopoeia from 1831 to 1936. Its continued popularity has led to overexploitation: it is now rare in the wild, from which all trade supplies come (cultivation is difficult).
Growth
It requires moist, humus-rich soil and a shady position. Propagation is by seed sown in autumn, though germination is slow and erratic, or by division in early spring or late autumn. Plants do not establish easily.
Parts used
Rhizome dried for use in tinctures, decoctions and pharmaceutical preparations.
Uses
Medicinal
It has anti-inflammatory properties, helps to check bleeding, is also antibacterial, decongestant and mildly laxative. Popular in North America for boosting the immune system, taken as a tea in combination with other herbs, such as Echinacea purpurea.