Cordeauxia edulis

Cordeauxia edulis is a plant in the family Fabaceae and the sole species in the genus Cordeauxia. Known by the common name yeheb bush, it is one of the economically most important wild plant at the Horn of Africa, but it is little known outside of its distribution area. It is a multipurpose plant, which allows the survival of nomads by providing them with seeds. Further the bush serves forage for livestock, firewood and dye. Its wild population is currently declining. Because it is potentially valuable for other hot, dry regions as a resource for food and fodder, it's recommended to take measures against its extinction. Cordeauxia edulis Hemsl. is a leguminous plant (Fabaceae) from the genus Cordeauxia. The genus Cordeauxia is closely related to Caesalpinia and Stuhlmannia. There are at least two varieties of the species C. edulis: Moqley and Suley. Moqley has smaller and darker leaves as well as a smaller stem diameter than Suley. Furthermore, the pods of Moqley include just one seed whereas the pods of Suley contain several smaller seeds. The seeds of Moqley are claimed to be sweeter. The common name of C. edulis is Yeheb-Nut (English) or Yeheb (French). Other names are Yebb, Hebb, Ye’eh, Yi-ib, Yehib or Yicib. In amharic it is called Ehb, Qud or Quda. The yeheb nut bush has been known to the Somali nomads for centuries. The first recovery of his existence dates back to 1871, when the Italian Robecchi noticed the plant when traversing Somalia to Bari. The bush has been named after Cordeaux, a botanic who first obtained botanical specimens in the Ogaden province (Ethiopia) which were found to be a leguminous plant belonging to a hitherto unknown genus in the Caesalpinaceae. Afterward, Hemsley gave the plant the generic name Cordeauxia, with the specific epithet edulis (edible).In 1929, the yeheb bush covered half of the vegetation of large territories in Somalia and south-east Ethiopia. In 1983 the distribution has been reduced to small regions. The yeheb tree is native in the arid and semi-arid areas in Somalia (Central) and Ethiopia (Ogaden). Its distribution has rapidly declined from 50% coverage down to only small locations nowadays. These regions are often semi-deserts or open bushy steppes located at altitudes from 100 to 300m. The rainfall rates are very low and frost does not occur. The ground is a very poor red sandy soils. The existence of C. edulis is threatened by war, over-utilization and by drought. Another cause for the decrease of C. edulis is the loss of seeds removed through the local people, eaten by wildlife and destroyed by insects. Its extinction would represent an irreplaceable loss for the long-term survival of the nomadic populations. In 1975, the National Range Agency of Somalia protected an area of about 50ha by prohibiting grazing. Since then, lots of other areas have been protected from grazing. In these areas and in all the native areas, the situation of Yeheb bush had considerably improved according to a 1983 study. However, a mission in 2015 found that the species had disappeared from the Haud plateau of Somaliland, although still to be found on the Ethiopian side of the border. It is exotic in Israel, Kenya, Sudan, Tanzania and in the Republic of Yemen. It is a wild species, but also subject to domestication trials, where it was sent to other arid regions, but with poor response, except for Voi, Kenya, where fruits are produced successfully since 1957. Today there is germplasm collection in Ethiopia (ILRI Addis Ababa), Kenya (National Genebank, Kikuyu) and the USA (Southern Regional Plant Introduction Station, Griffin, Georgia). It is an evergreen, multistemmed shrub of about 1.6m height but it can also grow up to 4 m. The Yeheb tree has a taproot system, which can go 3m deep. Like that it reaches deep water and can stay green all year round. C. edulis is cultivated on a small scale in Somalia and near Voi in Kenya. It has only recently been a subject to domestication, therefore little knowledge about propagation, the agronomic practices and its potential for selection as well as breeding exists. The potential of this multipurpose plant is very promising, especially for other arid, hot regions as an important food and fodder resource. C. edulis is a drought resistant plant and tolerant to desertification. For optimal plant development, average temperature and rainfall requirements are 25 °C and 250 - 400mm/year (two rainy seasons). Occasionally the Yeheb tree can also cope with minimal precipitation levels of 150–200 mm/year. It grows on red sandy soils (called Haud) with a low nitrogen content. The soils are alkaline and their texture is fine to coarse sand or grit to loamy sand. C. edulis prefers elevated stands, where no water accumulates. It grows in altitudes between 100–1000 m and is found in vegetation with acacia-commiphora deciduous bushland and thickets.