 Ephedra |
Common Names
Mormon-tea or joint-fir family (1),
[Chinese].
Taxonomic notes
Many authors designate it the sole family in Order Ephedrales.Description
Plant: Shrubs or vines, erect or climbing, dioecious (very rarely monoecious) (1).Bark: Grey to reddish brown, cracked and fissured, often fibrous (1).
Branches: Numerous, terete, whorled to fascicled, finely longitudinally grooved, internodes 1-10 cm. Roots generally fibrous (1).
Leaves: Mostly not photosynthetic; simple, scalelike, opposite and decussate or whorled, connate at base to form sheath, generally ephemeral; resin canals absent. Cotyledons 2 (1).
Pollen cones: 1-10 in whorls at nodes, each compound cone composed of 2-8 sets of opposite or whorled membranous bracts, proximal bracts empty, distal bracts each subtending a small cone composed of 2 basally fused bracteoles subtending a sporangiophore bearing 2-10(-15) sessile to long-stalked, bilocular, apically dehiscent, pollen-producing microsporangia. Pollen prolate, with 6-12 longitudinal furrows, not winged (1).
Seed cones: 1-10 in whorls at nodes of twigs, each compound cone sessile or on short to long peduncle, composed of 2-10 sets of overlapping, opposite or whorled, membranous or papery to fleshy bracts, proximal bracts empty, most distal bracts subtending 1 axillary cone composed of a pair of fused bracteoles enclosing a single-integumented ovule with integument projecting as tube from bracteole-envelope, envelope forming a leathery"seed coat" that is shed with seed (1).
Seeds: 1-2(-3) per compound seed cone, yellow to dark brown, smooth or furrowed (1).
Wood: Ring porous with wide multiseriate rays and vessels in older stems (1).
Range
In tropical to temperate climates, worldwide except Australia (1). Most species are found in semiarid habitats.Big Tree
Oldest
Dendrochronology
No record of use for any species.Ethnobotany
Throughout its distribution it is used by native cultures for a variety of medicinal purposes, including cough medicines, an antipyretic, an antisyphilitic, a stimulant for poor circulation, and an antihistamine. These uses are based on the presence of tannins and alkaloids, particularly ephedrines (1). In recent times, it has achieved widespread popularity (e.g., over 7000 Web pages!) as an 'herbal medicine' used in weight-loss preparations and 'energy' preparations (both uses due to its stimulant effects) and cold and allergy medications (due to the presence of the bronchodilator ephedrine) (2).Observations
Remarks
Citations
(1) Dennis W. Stevenson at the Flora of North America online.(2) Herbal Information Center. No date. Ephedra (Ephedra sinica). Article posted at the URL http://www.kcweb.com/herb/ephedra.htm, accessed 21-Feb-1999.
See also:
Kubitzki, K. 1990. Ephedraceae. In: K. Kubitzki et al., eds. 1990+. The Families and Genera of Vascular Plants. Berlin etc. Vol. 1, pp. 379-382.
Markgraf, F. 1926. Ephedraceae. In: H. G. A. Engler et al., eds. 1924+. Die natürlichen Pflanzenfamilien..., ed. 2. Leipzig and Berlin. Vol. 13, pp. 409-419.
Meyer, C. A. von. 1846. Versuch einer Monographie der Gattung Ephedra. Mém. Acad. Imp. Sci. Saint-Pétersbourg, Sér. 6, Sci. Math., Seconde Pt. Sci. Nat. 5(2): 225-298.
Parlatore, F. 1868. Gnetaceae. P.352-359 in A. P. and A. L. P. de Candolle (eds.), 1823-1873. Prodromus Systematis Naturalis Regni Vegetabilis.... Paris etc. Vol. 16, part 2.
Stapf, O. 1889. Die Arten der Gattung Ephedra. Denkschr. Kaiserl. Akad. Wiss., Wien. Math.-Naturwiss. Kl. 56(2): 1-112.
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This page is from the Gymnosperm Database
URL: http://www.geocities.com/~earlecj/ep/index.htm
Edited by Christopher J. Earle
E-mail:earlecj@earthlink.com
Last modified on 27-Feb-1999