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Acacia seyal Del.
Mimosaceae
Shittim Wood, White Whistling wood
Source: James A. Duke. 1983. Handbook of Energy Crops. unpublished.
- Uses
- Folk Medicine
- Chemistry
- Description
- Germplasm
- Distribution
- Ecology
- Cultivation
- Harvesting
- Yields and Economics
- Energy
- Biotic Factors
- References
According to some Biblical scholars, the Shittah tree is mentioned in the Bible
only once (I will plant in the wilderness... the Shittah tree. Isaiah
41), but its wood is referred to many times as shittium, which is the plural of
shittah in Hebrew. Some even speculate that it was only natural that Moses
should turn to shittium when he came to build the Ark of the Covenant and the
Tabernacle and needed beams and timber. No one can really be sure which
species of Acacia was meant. Wood is white to yellow-brown, finely-striated
with dark lines, coarse-grained, soft, easy to work, polishes well, but
discolors eastly with mold and is susceptible to insect attack. Ancient
Egyptians made coffins, some still intact, from the wood. Nigerians used
sapling stems, or also the roots for spear shafts. Tree also yields a gum of
good quality, inferior to that of A. senegal. Systematic tapping has
produced a product of better color and taste. Bark contains tannin and yields
a red liquid extract. The gum is said to be edible. The leaves are important
for forage and the wood for fuel where the trees are abundant. In parts of
Africa the tree is important for livestock, natives driving their animals to
where it is common and lopping off branches for them, both leaves and young
pods being eaten. The pods are sold, especially for fattening sheep. The tree
is believed to provide the best firewood in Chad, and the best fodder in
Sahelian savannas (NAS, 1980a; Duke, 1983a).
The gum is believed to be aphrodisiac. The bark decoction Is used for
dysentery and leprosy. Tanganyikans use the bark as a stimulant in tropical
Africa. The gum is used as emollient and astringent for colds, diarrhea,
hemorrhage and ophhthalmia. Mixed with Acacia sieberana DC, it is used
for intestinal ailments on the Ivory Coast. Wood used as a fumigant for
rheumatic pains, and to protect puerperal mothers from colds and fevers.
Eating the gum is supposed to afford some protection against bronchitis and
rheumatism (Duke, 1983a).
This species has been reported to contain 1820% tannin.
Tree 312 m tall, crown flat-topped; bark powdery, white to greenish-yellow or
orange-red; sparsely branched, the branches horizontal or ascending; young
branchlets with sparse hairs or almost glabrous, with numerous reddish sessile
glands; epidermis of twigs becoming reddish and shed annually; leaves often
with a large gland on petiole and between the top 12 pairs of pinnae; stipules
spinescent, up to 8 cm long, ant-galls present or absent; pinnae usually 37
pairs, the leaflets in 1120 pairs, 38 cm long, 0.751 mm wide, sparingly
ciliolate or glabrous; lateral veins invisible beneath; flowers bright yellow,
in axillary, pedunculate heads 1013 mm across, borne on terminal or short
lateral shoots of current season; involucel in lower half of peduncle 24 mm
long; apex of bracteoles rounded to elliptic, sometimes pointed; calyx 22.5 mm
long, puberulous in upper part; corolla 3.54 mm long, glabrous outside; pods
720 cm long, 0.50.9 cm in diameter, dehiscent, falcate, constricted between
seeds, glabrous except for sessile glands, 69-seeded; seeds elliptic, 79 mm
long, 4.55 mm wide, compressed, minutely wrinkled, olive-brown to olive;
areole 56 mm long, 2.53.5 mm wide.
Species has several botanical varieties. The two main ones are: A. seyal
var. fistula (Schweinf.) Oliv. (A. fistula Schweinf.), is white-barked
with some pairs of spines fused at base into 'ant-galls', 0.83 cm in diameter,
grayish or whitish, often marked with sienna-red and with longitudinal furrows
down center, more or less 2-lobed. Found in Zambia, Malawi, and Mozambique.
A. seyal var. multijuga Schweinf. ex Baker f. (A.
stenocarpa Oliv., pro partem), a shrub or tree, usually less than 5 m tall,
sometimes up to 13 m, flattened crown; bark on main stem greenish-brown,
peeling in papery rolls; bark on branchlets red-brown, thorns straight, weak,
usually less than 2.5 cm long, sometimes absent; pinnae 412 pairs, leaflets
1020 pairs; flowers golden-yellow; pod narrow-linear, strongly curved, up to
10 cm long, 0.6 cm wide, dehiscing on tree. Common in overgrazed pastures and
widely distributed in East Africa. Hybrids, A. seyal var.
fistula X A. xanthophloea Benth., are known from woodlands on
black clay loams on flood plains in Malawi. Pods are conspicuously irregular,
411 cm long, 610 mm wide, ill-formed and curved. Assigned to the Africa
Center of Diversity, shittim wood or cultivars thereof is reported to exhibit
tolerance to high pH, heavy soil, insects, mycobacteria, poor soil, salt,
savanna, slope, and waterlogging. (2n= 26.)
Native to the Sahelian Zone from Senegal to Sudan, it also occurs in Egypt and
eastern and southern Africa, from Somalia to Mozambique and Namibia (NAS,
1980a).
Trees thrive in Sclerocarya caffra woodlands, wooded grasslands and
especially on seasonally flooded black-cotton soils along water courses.
Requires a heavy clay-alluvium, but will grow on stony ground at base of hills.
Grows at 202,100 m altitude. A gregarious savanna tree, ranging from
Subtropical Desert to Dry through Tropical Desert to Very Dry Forest Life
Zones, shittim wood is reported to tolerate annual precipitation of 8.722.8 dm
(mean of 7 cases = 15.0 dm), annual mean temperature of 18.727.8°C
(mean of 7
cases = 24.0°C) and pH of 5.08.0 (mean of 5 cases = 6.9).
Propagated from scarified seed. large cuttings are said to strike root readity
in moist soils.
Pods, bark or wood are harvested in season from trees or shrubs in native
habitats. Gum also obtained from native plantings, in manner similar to that
for other gum arabic plants.
The dense wood is highly prized for firewood, in areas where few other plants
survive. Considered one of the best firewoods in Chad, it is used in the Sudan
to make fragrant fires over which women perfume themselves.
Following fungi reported on this plant: Fomes rimosus, Ganoderma
lucidum, Leveillula taurica, Ravenelia volkensii, Trametes meyenii, and
Uromyces schweinfurthii. Although the plant is reportedly resistant to
insect attacks, felled logs may be severely damaged by wood borers.
- Duke, J.A. 1983a. Medicinal plants of the Bible. Trado-Medic Books, Owerri,
NY.
- N.A.S. 1980a. Firewood crops. Shrub and tree species for energy production.
National Academy of Sciences, Washington, DC.
Complete list of references for Duke, Handbook of Energy Crops
Last update December 19, 1997