Common name: Desert date

Desert date is a fruiting shrub or small tree native to dry parts of Africa and the Middle East.

The plant is typically 5 to 10 m (16 to 33 ft) tall, and in tree form, develops a straight, short trunk and a rounded crown. The branches are ascending then divide into many drooping branchlets armed with long sharp thorns. The bark is grey-brown and flaking.

Leaves are compound, comprised of two small dull-green oval leaflets fused at the base and divided at the tip. They fall off the tree in the dry season to conserve water, with the new leaflets emerging at the start of the rainy season, along with the flowers.

Flowers small with five greenish-yellow petals and with a sweet fragrance. They are followed by small egg-shaped and -sized fruit with leathery skin that are green when young, becoming yellow when ripe. They have sticky, fibrous yellow-orange pulp surrounding a single seed.

Use

Desert date fruit are classed as a minor fruit and are best eaten dried similar to dates, though it is reported that children in its native range are fond of the fresh fruit. Fruit quality varies considerably, ranging from sweet to bitter, depending on the type or variety. The trees are highly productive, producing hundreds of fruit in a season.

The wood is moderately heavy, averaging around 700 kgs per cubic meter (44 lbs per cubic ft). Selected stems are cut and shaped into tool handles, walking sticks, kitchen utensils and other durable articles, as well as being used for firewood and making charcoal.

Goats actively browse on the leaves and fallen fruit which combined have a crude protein content of around 11% of their dry weight.

The seed kernel yields, on expression, a clear, tasteless oil known as 'Betu oil' or 'Zachun oil' that is used traditionally to make soap or burnt in lamps for light. It has also reportedly been successfully engine-tested as a Biodiesel. It is also an edible oil and has good frying properties, comparable to cottonseed and peanut oils.

General interest

Desert date and other drought-tolerant species of the Sahel region in North Africa have been planted in high numbers to create what has become known as the 'Great Green Wall', a mammoth initiative against the encroaching Sahara Desert.

The goal is to create a multi-species belt of vegetation across the African continent, spanning over 7,000 kilometres (4350 miles) east to west and 15 kilometres (9 miles) in width. Other species identified as suitable for the project include Gum Arabic (Senegalia senegal), Jujube (Ziziphus jujuba) and Gao tree (Faidherbia albida).

Climate

Grows naturally in dry to sub-humid subtropical and tropical lowlands to mid-elevation climates, generally areas with annual lows of 13 to 25°C, annual highs of 24 to 37°C, annual rainfall of 300 to 1000 mm and a dry season of 7 to 10 months, extending to 12 months with irrigation or groundwater.

Growing

New plants are usually grown from seed that germinate readily. It performs well on free-draining clay, loam and sand soils of a slightly acid to alkaline nature, generally with a pH of 6.5 to 8.5, and on sites with full sun exposure.

Problem features

Its high fruit production, good seed germination rate and vigorous suckering habit cause it to be potentially invasive. It is listed as a weed in at least one reference publication and is reported to have colonised parts of the island of Curacao in the Caribbean. The sharp thorns can cause serious injury.

Books

• Arbonnier, M. 2004, Trees, shrubs and lianas of West African dry zones, CIRAD, Margraf Publishers Gmbh, MNHN, Paris

• Axtell, B. L & Fairman, R. M 1992, Minor oil crops, Food and Agriculture Organization of the United Nations (FAO), Rome

• Booth, F. E. M. & Wickens, G. E. 1988, Non-timber uses of selected arid zone trees and shrubs in Africa, Food and Agriculture Organization of the United Nations (FAO), Rome

• Bradbear, N. 2009, Bees and their role in forest livelihoods : a guide to the services provided by bees and the sustainable harvesting, processing and marketing of their products, Food and Agriculture Organization of the United Nations (FAO), Rome

• Dastur, J. F. 1964, Useful plants of India and Pakistan : a popular handbook of trees and plants of industrial, economic, and commercial utility, 2nd ed., D. B. Taraporevala Sons, Bombay

• Food and Agriculture Organization of the United Nations (FAO) 1988, Traditional food plants : a resource book for promoting the exploitation and consumption of food plants in arid, semi-arid and sub-humid lands of eastern Africa, Food and Nutrition Paper No. 42, Rome

• Gohl, B. 1981, Tropical Feeds : feed information summaries and nutritive values (Revised edition), Food and Agriculture Organization of the United Nations (FAO), Rome

• Goodin, J. R & Northington, D. K. 1985, Plant resources of arid and semiarid lands : a global perspective, Academic Press, Orlando

• Hines, D. A., & Eckman, K. 1993, Indigenous multipurpose trees of Tanzania: uses and economic benefits for people, Cultural Survival Canada

• Hocking, D. 1993, Trees for drylands, International Science Publisher, New York

• Jamieson, G. S. 1943, Vegetable fats and oils : their chemistry, production, and utilization for edible, medicinal and technical purposes, 2d ed, Reinhold, New York

• Janick, J., & Paull, R. E. 2008, The encyclopedia of fruit & nuts, CABI Publishing, Wallingford, Oxfordshire

• Krishen, P. 2006, Trees of Delhi : a field guide, Dorling Kindersley Publishers, Delhi

• Macmillan, H. F. 1943, Tropical planting and gardening : with special reference to Ceylon, 5th ed, Macmillan Publishing, London

• Martin, F. M., et al. 1987, Perennial edible fruits of the tropics : an inventory, U.S. Dept. of Agriculture (USDA), Agricultural Research Service, U.S. Government Printing Office (GPO), Washington, D.C.

• Menninger, E. A. 1977, Edible nuts of the world, Horticultural Books, Stuart, Florida

• Nair, P. K. R. 1993, An introduction to agroforestry, International Centre for Research in Agroforestry (ICRAF), Kluwer Academic Publishers, Dordrecht

• National Research Council (Board on Science and Technology for International Development) 1983, Firewood crops : shrub and tree species for energy production (Volume 2), The National Academies Press, Washington D. C.

• National Research Council (Board on Science and Technology for International Development) 2008, Lost Crops of Africa: Volume III: Fruits, The National Academies Press, Washington D. C.

• Parrotta, J. A. 2001, Healing plants of peninsular India, CABI Publishing, Wallingford, Oxfordshire

• Randall, R. P. 2002, A global compendium of weeds, R.G. and F.J. Richardson Press, Melbourne

• Reyes, G. 1992, Wood densities of tropical tree species, U.S. Department of Agriculture, Forest Service, Southern Forest Experiment Station, New Orleans, Louisiana

• Roecklein, J. C & Leung, P.S. 1987, A Profile of economic plants, Transaction Books, New Brunswick, New Jersey

• Tredgold, M. H. 1986, Food plants of Zimbabwe : with old and new ways of preparation, Mambo Press, Gweru, Zimbabwe

• Wickens, G. E & Day, Peter R., 1928- & Haq, N & International Symposium on New Crops for Food and Industry 1989, New crops for food and industry, Chapman and Hall, London ; New York

Articles, Journals, Reports and Working Papers

• Dagar, J. C. & Singh, G. 2007, Biodiversity of Saline and Waterlogged Environments: Documentation, Utilization and Management, NBA Scientific Bulletin, (9), 78.

• National Research Council (Board on Science and Technology for International Development) 1990, Saline agriculture : salt-tolerant plants for developing countries, The National Academies Press, Washington D. C.