Argania spinosa (L.) Skeels

Sapotaceae

Common name(s):

Arganier (French); Argane, Ardjane (Berber)

Description:

Tree usually 4-6 m in height, but sometimes reaching 10 m, with a rounded, sometimes umbrella-shaped canopy. It has a twisted trunk with a cracked bark. Branching is very dense and spiny. Leaves are alternate, tough, often clustered in bundles, lanceolate to sharply lanceolate, sometimes slightly spatulate, persistent or sub-persistent, petiole not very distinct.  Flowers are greenish, clustered in axillary balls, sessile, with two basal bracts, five pubescent sepals slightly connate at the base, bell-like corolla, five stamens alternating with five staminoids; one style equal to or protruding beyond the stamens. Fruit or “organ nut” is a green-yellowish drupe, containing 2-3 seeds joined together as a pseudo-kernel, the size of an olive or walnut.

Distribution:

Restricted to southern Morocco, in particular the region of Agadir. Bio-climate, Saharan to lower semi-arid, warm to mild variants. Highest altitude: 1 500 m on the southern slopes of the Grand Atlas, and 1 700 m on the western slope of the Anti-Atlas.  Almost indifferent to soil quality, except that the species avoids drifting sands and water-logged soils. The species needs 100-300 mm of precipitation.

Propagation:

Attempts at introduction in other Mediterranean countries have succeeded, for example, in the south of Tunisia (Matmata). The seed germinates readily in its native area; the sprout is conspicuous within a month and young trees start producing fruits at the age of 5-6 years.

Products and uses:

The fleshy parts of the fruit and the leaves are consumed by livestock, especially goats. The wood makes good charcoal. The kernel produces Argan oil; the seed is roasted before the oil is expressed in order to eliminate saponins. Then the nut is ground and mixed with tepid water. The oil floats and is separated by precipitation; at this stage, it is brownish and of an acrid, unpleasant taste. Left to rest, residues deposit, the colour lightens, but the oil keeps a very strong flavour. It is sometimes consumed in that form or purified though emulsion with water or simply by adding some bread. While the nut is very bitter, the purified oil is as sweet as walnut oil. The oil content rarely drops below 66% in healthy seeds. The oil is also used for making nice, hard yellowish soap.

Main References:

Baumer, M. 1983. Notes on Trees and Shrubs in Arid and Semi-arid Regions. FAO/UNEP programme “Ecological Management of Arid and Semi-Arid Rangelands in Africa, Near and Middle East” (EMASAR Phase II). 270p.