TheImprovement ofTropical and Subtropical Rangelands

POTENTIAL 0' FAIDHERBIA 'OR DESER:rlI'lOATION OONTROL 353
land management program may evolve that could include all aspects
of agricultural and livestock production development.
The final goal is a culturally acceptable, ecologically oriented
program for integrated land management. This integrated development
approach to ecological stability in the Sahel may be termed
an agro-sylvo-pastoral approach, signifying a unification of efforts.
(Agro-sylvo-pastoral is becoming a popular term used in francophone
Africa to imply the cooperative development efforts of the agricultural
[agro-] , sylvicultural [sylvo-], and range management [pastoral]
disciplines.)
CHARACTERISTICS OP FAIDHERBIA ALBIDA
Faitllaer6ia tJl6itla, or Acacia tJl6itla, is referred to in Arabic as the
laaraz. It is a member of the legume family and of the subfamily Mimosoideae.
The species is characterized by bipinnate leaves, orange
curled seed pods, cream-colored flowers, and thorns.
Faitllaer6ia tJl6itla reachs heights of3-10 min 10 years, depending
on environmental conditions (Wickens, 1969). It may grow as a shrub
ifcontinually grazed (Wickens, 1969), but usually develops into a tree
with a large spreading crown. The mean maximum height is 25 m,
with a girth of 5 m (United Nations Development Programme and
Food and Agriculture Organization of the United Nations, 1968). It
is a long-lived species, with an average life span of 70-90 years in the
Sudan and known to live more than 150 years in Zambia (Wickens,
1969).
Faitllaer6ia tJl6itla has an extensive taproot system that develope
rapidly to reach an adequate moisture layer. This characteristic
makes the species relatively drought-resistant. On the coarse alluvial
sands of the Sudan, a 6-month-old seedling with 8 cm ofareal growth
had a taproot of 70 cm (Wickens, 1969). A 3-year-old seedling
excavated in northem Nigeria produced a taproot in excess of 9.9 m
(Weber, 1978).
The most unusual phenological characteristics of the species are
retention of the leaves during the dry season and shedding of leaves
at the onset of the wet season. No other African savanna species is
known to posaeaa this reverse deciduous cycle (Wickens, 1969; Weber,
1978).
In Africa, Faitllaer6ia tJl6itla is found wherever there is a long
dry season: from southern Algeria to Transvaal and from the Atlantic
to the Indian Ocean (Giffard, 1964). It prefers a well-drained