Epimedium perralderianum (barrenwort)
Barrenwort is an evergreen, herbaceous perennial with stiff, heart-shaped leaflets and spikes of small, yellow flowers in spring.
Detail of an illustration of Epimedium perralderianum
Epimedium perralderianum Coss.
barrenwort, bishop’s mitre (names used for Epimedium species in general).
Vulnerable according IUCN Red List criteria (1998).
Oak woodland and Atlas cedar (Cedrus atlantica) forest.
About this species
Epimedium perralderianum was named by the French botanist Ernest Saint-Charles Cosson (1819-1889) in memory of his friend Henri de la Perraudière, who died as a result of a fever on an expedition to Mount Babor (Algeria) in 1861, during which this species was discovered.
E. perralderianum is a perennial plant forming spreading patches of tough, evergreen leaves, each with three heart-shaped, spiny-edged leaflets. The small yellow flowers are produced on leafless spikes in the spring.
Geography and distribution
Native to north-eastern Algeria, where it grows in the oak and cedar forests of Mount Babor, at 1,200–1,500 m above sea level.
Moist forests of North Africa
Epimedium perralderianum is one of the interesting species found in the relicts of moist forest in the North African mountains. The closely related E. pinnatum subspecies colchicum grows in the moist forests of the Black Sea coast in north-eastern Turkey.
Mount Babor (Djebel Babor) in Algeria is one of the wettest places in North Africa (with 2,000–2,500 mm average annual rainfall). It contains the last remnants of forests which covered much of North Africa during the glacial maximum 20,000 years ago. Oaks, holly, yew, aspen and Acer opalus subsp. obtusatum are all found here, along with Atlas cedar (Cedrus atlantica), which occurs from around 1,200 m above sea level in mixed woodland, and dominates at higher altitudes (above 1,800 m).
Part of the area is protected as the Djebel Babor Strict Nature Reserve.
The long-creeping rhizome (underground stem) is tough and wiry. The leaves are up to 20 cm long and are divided into three leaflets, each up to 6.5 cm long (or up to 10 cm in cultivation). The glandular flowering stems are up to 30 cm high and bear 9–25 flowers. The flowers are 1.5–2.3 cm across, and each has four small, greenish outer sepals and four large, yellow inner sepals 5–9 mm across. Each flower has four small (2.5 mm long) petals, with small, brown nectaries with an upward-curving spur 1–2 mm long. The stamens (male parts) are 5 mm long and bear yellow anthers (pollen-bearing structures).
Illustration from Curtis's Botanical Magazine
Curtis's Botanical Magazine (Editor: Martyn Rix) provides an international forum of particular interest to botanists and horticulturists, plant ecologists and those with a special interest in botanical illustration.
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Each four-part volume contains 24 plant portraits reproduced from watercolour originals by leading international botanical artists. Detailed but accessible articles combine horticultural and botanical information, history, conservation and economic uses of the plants described.
Published for the Royal Botanic Gardens, Kew by Wiley-Blackwell Publishing.
Threats and conservation
Epimedium perralderianum was listed as Vulnerable according to IUCN Red List criteria in 1998. It has a very restricted distribution in the wild, and is likely to be adversely affected by any deforestation.
Epimedium perralderianum is cultivated as an ornamental. It makes a good groundcover plant for moist, partially shaded places (such as in a woodland garden). Its leaves turn red in late summer and autumn.
Some Chinese species of Epimedium are used medicinally. For example, E. sagittatum is one of four source species of the Traditional Chinese Medicine (TCM) called ‘Yin Yang Huo’ (pharmaceutical name: Herba Epimedii). The aerial parts of the plant are used to treat impotence, rheumatoid arthritis, numbness and muscle contractions, and hypertension during menopause, among other conditions.
Epimedium perralderianum is easily grown in partial shade, preferably in places which do not dry out in summer. It can be propagated easily by division.
This species at Kew
Epimedium perralderianum is grown in the Woodland Garden (the area around the Temple of Aeolus) at Kew.
Dried and alcohol-preserved specimens of Epimedium perralderianum are held in Kew’s Herbarium, where they are available to researchers from around the world, by appointment. The details of one of these specimens can be seen online in the Herbarium Catalogue.
Davis, P.H. & Hedge, I. (1971). Floristic links between N.W. Africa and S.W. Asia. Ann. Nat. hist. Mus. Wien 75: 43-57.
Guowei, S. (2005). Pharmacopoeia of the People's Republic of China, Volume 1, English Edition. Chinese Pharmacopoeia Commission, People's Medical Publishing House, Beijing, China.
Hooker, J.D. (1880). Epimedium perralderianum Coss. Curtis’s Bot. Mag. 106: t. 6509.
Stearn, W.T. (2002). The Genus Epimedium. Royal Botanic Gardens, Kew.
Walter, K.S. & Gillett, H.J. (eds) (1998). 1997 IUCN Red List of Threatened Plants. Compiled by the World Conservation Monitoring Centre. IUCN – The World Conservation Union, Gland, Switzerland and Cambridge, UK.
Kew Science Editor: Martyn Rix
Kew contributors: Steve Davis and Chris Leon (Sustainable Uses Group)
Copyediting: Emma Tredwell
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