Description
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.