r.1 - part

Fig. 18. Distribution of Acacia tortilis in southern Africa (Coates Palgrave 1977).
Natural Distribution Extensive through Africa from southern part of
continent to tropical Sudan and Ethiopia and the Middle East to Israel, Saudi
Arabia, Yemen. Altitude lowland. Planted in other areas such as India on a
large scale for fuelwood.
Climate and Soils Arid or semidesert tropical, hot and dry, with long irregular
dry seasons. Annual rainfall 100-1000 mm. Maximum temperatures
about 50*C, minimum may be near 0°C. Soils various, including sand dunes,
sands, sandy loam, rocky, and alkaline. In shallow soil, plants shrubby but
develop long lateral roots.
Common in dry savannas, forming groves, and in other types such as
bushlands, thornbush, bushveld, lowveld. The last woody species bordering
the desert.
Extremely hardy and drought-resistant, this species can be grown under
severe arid conditions. Growth slow but relatively fast for dry zone tree.
Young plants not frost-hardy. Because of long lateral roots, plants can spread
to nearby fields and roads, becoming undesirable weeds. If introduced into a
humid climate, could become a serious pest.
Subspecies Species has 4 distinct subspecies (earlier named as species)
with different geographical ranges and different ecological zones and
tolerances. Thus, subspecies or geographical source should be considered
when seed is selected for plantations. These 4 subspecies are listed below wi n.
their ranges and taxonomic differences.
-Ssp. tortilis. Young twigs and leaf axes hairy; pods narrow, hairy, not
glandular, 3-5 mm wide. Egypt and Middle East to Palestine, Yemen, Arabia.
-Ssp. raddiana (Savi) Brenan (AcaciaraddianaSavi). Twigs, leaves, and pods
hairless or hairy; pods mostly hairless, not glandular, 6-9 mm wide. North
Africa and Middle East; Algeria to Egypt, Sudan, Kenya, Nigeria.
ACACIA TORTILIS
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