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GENERAL
Origin
:
sub-tropical,
tropical
Humidity
:
extremely arid,
very arid
Propagation :
sowing and
pricking out
Maintenance :
low
CONDITIONS
Urban climate :
resistant
Dessication :
resistant
Stagnant water :
vulnerable
Irrigation
:
low
Salinity/ppm :
high (3500 ppm)
Hardiness
:
-9°C
SHAPE
Type
:
tree
Height
:
8 m-10 m
Spread
:
8 m-10 m
Foliage
:
deciduous
FLOWER
Colour
:
white, pale
yellow
Period
:
February -
October
Smell
:
sweet, scented,
flower
FRUIT
Type of fruit :
pod
Fruit size
:
15 cm
A. gerrardii is a variable species. The variety iraquensis (sant al waraqi) has a rough, spiny trunk
and finely fissured, dark-coloured bark, which does not peel off in strips like that of the whitish
bark of A. gerrardii var. najdensis, (sant al najdi). The seeds of iraquensis are held in sickle-shaped,
flat pods which are beige-coloured, long and straight, and covered by fine, grey hairs. Those of
najdensis are strongly curled, almost circular pods, and a much darker brown. A. gerrardii has a
distribution in the northern part of the Arriyadh region and Saudi Arabia and is usually found in
depressions and watercourses. A small tree with ascending branches and a flattened crown. It has
a long, straight and single stem with a reddish bark. Young, strong branches are densely covered
with grey velvety hairs. Numerous thorns are arranged in pairs and white in colour, while mature
trunks are almost thorn-free. Singular, round, creamy-white, sweet-scented flowers appear from
October to February. During a very cold winter, the tree is deciduous. Propagated by seed, A.
gerrardii is fast-growing, hardy to about –10 °C, and drought-resistant. It will become a spreading
shade tree, when watered frequently. Its winter flowers make the tree an attractive species for
arid landscape design in both intensive and extensive landscape situations. It is suitable for most
gardens with a native look, and valuable for revegetation schemes, and roadside planting. Little
maintenance is required once trained well into a straight leader.
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Acacia gerrardii,
Mimosaceae
Grey-haired Acacia,
sant al waraqi