Rhamnus (genus)
Rhamnus alaternus
Buckthorn ( Rhamnus ), also Wegedornstrasse, forms a genus within the family of the buckthorn family ( Rhamnaceae ). It consists of about 100 species, which are common to a few regions worldwide.
- 5.1 Literature
- 5.2 Notes and references
Description
The species are mostly deciduous, rarely evergreen shrubs and small trees, often form the thorns. The leaves are simple and often sawn and are rarely in clusters on short shoots. The stipules are greatly exaggerated. The leaf arrangement is opposite or alternate. Some species form bud scales on the winter buds.
The flowers are inconspicuous, often hermaphrodite of greenish- white or yellowish color. The calyx is bell-shaped to cup-shaped and consists of four or five ovate - triangular sepals. The four to five petals are shorter than the sepals, rarely absent. There shall be four to five stamens, the anthers are fixed posteriorly. The ball-shaped, free-standing ovary are upper constant. The flowers appear singly, in cymes, in zymosen grapes or panicles.
There shall be leathery or fleshy, berry- like drupes with two to four cores, which are dispersed by birds. The fruits of most species contain a yellow color, the seeds plenty of protein and oils.
Dissemination
The species usually occur in temperate to tropical regions of the northern hemisphere, mainly in East Asia and North America, a few in Europe and Africa. You are missing only in Madagascar, Australia and Polynesia.,
System
There are different classifications of the genus Rhamnus, the septic trees ( frangula ) are often seen as a separate genus. The majority of the authors is divided the genus into two subgenera Eurhamnus frangula and which are further divided into sections. The following classification follows the system of Suessenguth:
- Subgenus frangula Miller, S.F. Gray
- Buckthorn ( Rhamnus frangula L.)
- Rhamnus rupestris Scop.
- Subgenus Eurhamnus Dippel
- Holly buckthorn or Evergreen buckthorn ( Rhamnus alaternus L.)
- Alpine Buckthorn ( Rhamnus alpina L.): without spines and with fourfold flowers from the southern mountains
- Balearic Islands buckthorn ( Rhamnus ludovici - salvatoris Chodat, syn. Rhamnus Balearica ( DC.) Willk. ): Occurrence in Mallorca and in eastern Spain ( With Valencia).
- Purgier buckthorn or buckthorn or only Wegedornstrasse ( Rhamnus cathartica L.): An upright shrub with large, sometimes fluffy hairy leaves and fleshy fruit
- Rhamnus fallax Boiss. Occurrence of Carinthia to Greece, without thorns
- Rhamnus L. lycioides
- Rhamnus myrtifolia Willk. Way from Spain
- Dwarf - buckthorn ( Rhamnus pumila Turra ): small-leaved dwarf shrub of the southern and central European mountain ranges
- Rhamnus tinctoria L.: species with broad leaves and thorns, deposits in Southeast European mountains, the dried berries are suitable for dyeing ( " yellow berry " )
- Rock buckthorn ( Rhamnus saxatilis Jacq. ): Densely branched and thorny species with very small leaves, deposits mainly in the mountains of Central and Southern Europe
Other types
- African buckthorn ( Rhamnus prinoides L' Hér. )
Use
The oil of the seeds is used for the preparation of lubricating oil, printing ink, and soap. The roots and leaves of some species used as remedies.