Christ's thorn  (Ziziphus spina-christi)

Christ’s thorn has yet to be classified by the IUCN.

Forming dense, sometimes impenetrable thickets, Christ’s thorn (Ziziphus spina-christi) grows as a shrub or small tree, armed with short spines that are positioned in pairs along the branches, one of which is straight and the other curved or hooked (2) (3). Christ’s thorn is covered in whitish-brown or pale grey bark which is deeply fissured and cracked, with a twisted trunk which branches widely, drooping at the ends to form a rounded, usually umbrella-shaped crown. The simple, alternate leaves are oval, becoming more pointed at the tips, with three conspicuous veins running along the length. The leaves are hairless on the upper surface, with a fine, downy covering of small hairs on the underside. Christ’s thorn produces small, greenish-yellow flowers, which cluster tightly in the axils of the leaves, and red-brown coloured, small, fleshy fruits that enclose a hard stone in the centre (2) (3) (4).

Referred to throughout history by many cultures and religions as a sacred or holy tree, Christ’s thorn has also traditionally been used in medicine, carpentry and as a source of food (5). 

Christ’s thorn is found in West and North Africa, the Middle East, northwest India and the eastern Mediterranean (2) (3) (4). 

Christ’s thorn is typically found in areas of relatively low rainfall and is capable of growing in areas of desert or semi-desert where the soils are often silty (containing fine deposits of mud and clay particles) (2) (3). It grows up to elevations of around 600 metres, although it has been reported at 1,500 metres in the United Arab Emirates (3).

Christ’s thorn is extremely drought tolerant, due in part to the presence of long, deep taproots which facilitate the plants ability to reach underground water sources. Christ’s thorn usually flowers between August and December, with fruits produced between October and January. The seeds of this desert plant (the hard stone in the centre of the fruit) have tough, woody coats and it is thought that in order to germinate, they must first pass through the digestive tracts of an animal to break down the outer layers (3) (4).

Christ’s thorn is not currently listed on any specific conservation legislation and is still considered to be widespread and fairly common throughout much of its range. However, it is thought that in parts of Sudan, stands of this hardy plant are quickly coming under threat as a result of intensive livestock browsing and over-collection (3). In addition, reports from some locations suggest that Christ’s thorn is susceptible to invasion and parasitism by the mistletoe Plicosepalus acaciae, which is causing premature senescence (aging) and increased mortality of this species (6).

There are no known conservation measures currently in place for Christ’s thorn.

Environment Agency - Abu Dhabi is a principal sponsor of ARKive. EAD is working to protect and conserve the environment as well as promoting sustainable development in the Emirate of Abu Dhabi.

To find out more about conservation in the United Arab Emirates, see:

• Environment Agency, Abu Dhabi:
  http://www.ead.ae/en/