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GENERAL
Origin
:
tropical
Vigour
:
fairly fast
growing
Humidity
:
extremely arid,
very arid, semi-
arid
Propagation :
sowing and
pricking out
Maintenance :
low
CONDITIONS
Urban climate :
resistant
Dessication :
resistant
Stagnant water :
vulnerable
Irrigation
:
low
Salinity/ppm :
moderate (2000
ppm)
Hardiness
:
-6°C
SHAPE
Type
:
tree
Height
:
12 m
Spread
:
14 m
Foliage
:
evergreen
FLOWER
Colour
:
white
Period
:
March - July
FRUIT
Type of fruit :
pod
Fruit size
:
15 cm
A flat-topped tree, A. tortilis is ubiquitous in arid regions of Africa and widespread in Saudi
Arabia, where it is known as samur. It tolerates the severe desert environment, as well as being
hardy to frost, although it is vulnerable until established. With multiple spreading trunks and
the typical silhouette of an inverted triangle;
A. tortilis
ssp.
raddiana
occurs in northern Africa
extending through Egypt to Saudi Arabia. Its crown is often irregularly rounded, and young
branchlets, leaves and pods are glabrous. It grows in wadis and sandy plains, usually in water
catchment areas. With small, highly aromatic, creamy-white flowers in tight clusters appearing
from spring to summer, the tree has characteristic, spirally twisted seed pods rolled up into a tight
coil. Evergreen with small feathery leaves, which line the thorny twigs, it has a moderate growth
rate and prefers sandy soils while accepting most others. It has a very deep taproot. A.tortilis is a
key species in greening deserts in the Middle East, being important for people and domesticated
animals; it also improves soil fertility. Propagation is by fresh, scarified, or boiled seed. It has
landscape value as a hedge or windbreak and in afforestation, but is unsuitable for planting
near to pedestrians because of its shape and thorns. Irrigation is necessary until well established,
but deep watering during the summer will enhance growth. Low maintenance only, except for
pruning to improve appearance; can be trained as a standard single leader tree.
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Acacia tortilis
ssp.
raddiana,
Mimosaceae
Twisted Acacia,
samur