Gourt Home::Gourt :: Epimedium
Epimedium, also known as Barrenwort, Bishop's Hat, Fairy Wings, Horny Goatweed, or Yin Yang Huo (Chinese : 淫羊藿), is a genus of about 25 species of herbaceous flowering plants in the family Berberidaceae. They are native to southern Europe, and central, southern and eastern Asia.
Epimedium species are hardy perennials. They have four-petaled "spider-like" flowers in spring or early summer.
Many species of Epimedium are reported to have aphrodisiac qualities. According to legend, this property was discovered by a Chinese goat herder who noticed sexual activity in his flock after they ate the weed. It is sold as a health supplement, usually in raw herb or pill form and sometimes blended with other supplements.
The "active ingredient" in Epimedium is icariin, which can be found in standardized extracts to be from 5% up to 60% potent. Strengths above that are usually reserved for lab use.
Horny Goat Weed works by increasing nitric oxide levels, which relax smooth muscle. This lets more blood flow to the penis or clitoris or other smooth muscle.
In addition to this mechanism, it also acts as a mild PDE-5 inhibitor. PDE-5 is an enzyme which is produced in a 'negative feedback" loop. As more blood flows to the genitals starts to flow, PDE-5 metabolizes the nitric oxide almost as fast as it is being produced to keep it in check. If the body does not produce enough of this enzyme, damage to the erect penis could result from too hard of an erection. This is called priapism. Viagra, a popular pharmaceutical, works by blocking the production of the PDE-5 enzyme. Horny Goat Weed produces small amount of PDE-5 inhibitors within safe levels.
Cultivation
Many species, hybrids, and cultivars are grown for ornament, particularly as ground covers for partial shade. The evergreen species are particularly good at keeping down weeds; the deciduous ones often have attractively colored new foliage in spring. One of the more popular cultivars is the Persian barrenwort E. x versicolor 'Sulphureum', also known as the Bicolor barrenwort, which produces soft yellow flowers in the spring. This plant is very tough and adaptable, being drought-tolerant in shaded to partly shaded conditions when established; it is a hybrid of E. grandiflorum x E. pinnatum ssp. colchicum.External links
- Botany.com page on ornamental Epimedium
- BBC Gardening page ditto
- A hobbyist's page of photographs
- Alternativehealing.org's page on use in traditional Chinese medicine
- IronMagazine's page on Epimedium as a supplement
- Discovery Health Article By Chris Kilham
Further reading
- William T. Stearn, The Genus Epimedium, revised edition 2002, ISBN 0-88192-543-8
"Epimedium"