Acacia albida Del.
Apple-Ring Acacia, Ana Tree, Winter Thorn
Source: James A. Duke. 1983. Handbook of Energy Crops. unpublished.
- Folk Medicine
- Yields and Economics
- Biotic Factors
Acacia albida is a widely used tree well documented for increasing the
yields of crops grown under it. According to VITA (1977) "A. albida is
highly valued in conservation efforts. It is the only species which loses its
leaves during the rainy season; therefore, farming under these trees is not
only possible but profitable." It is held sacred by the Africans of the
Transvaal. In Nigeria, the pod is used as camel food. The gum that exudes
spontaneously from the trunk is sometimes collected like gum arabic. The
timber, though straight grained, close, and weighty, is soft, fibrous, and
unsuitable for agricultural implements (Watt & Breyer-Brandwijk, 1962).
One writer even questions its value for fuel wood. Masai use it as the soft
flat wood upon which the firestick is twirled to make fire. Wood is used for
canoes, mortars, and pestles. The bark is pounded in Nigeria and used as a
packing material on pack animals. Ashes of the wood are used in making soap
and as a depilatory and tanning agent for hides. VITA (1977) says the wood is
used for carving; the thorny branches useful for a natural barbed fence. Pods
and foliage are highly regarded as livestock fodder. Some 90% of Senegalese
farmers interviewed by Felker (1981) collected, stored, and rationed Acacia
alba pods to livestock. Rhodesians use the pods to stupefy fish. Humans
eat the boiled seeds in times of scarcity in Rhodesia. Apparently it is
erroneously taken as an indicator of a shallow well site.
Reported to serve as an emetic in fevers (Masai), taken for diarrhea in
Tanganyika. Also used for colds, diarrhea, hemorrhage, and ophthalmia in West
Africa. The bark of the Ana tree is a folk remedy for diarrhea among several
tribes. On the Ivory Coast it is used for leprosy. The bark decoction
curtails nausea. A liniment, made by steeping the bark, is used for bathing
and massage in pneumonia. The bark infusion is used for difficult delivery,
and is used as a febrifuge for cough (Irvine, 1961). Pods worn as charm by
African women and children to avert smallpox.
The following table is reproduced, with permission from FAO's Tropical Feeds
Nutritive Table (Gohl, 1981)
| || ||As % of dry matter|
| ||DM ||CP ||CF ||Ash ||EE ||NFE ||Ca ||P|
|Fresh flowers, Sudan ||17.8 ||19.0 ||12.5 ||9.7 ||1.6 ||57.2|
|Fresh whole leaves, Niger || ||19.7 ||19.6 ||7.2 ||1.6 ||51.9 ||1.00 ||0.23|
|Fresh leaflets, Sudan ||36.3 ||17.1 ||12.4 ||8.4 ||2.3 ||59.8|
|Pods, Tanzania || ||8.8 ||24.4 ||3.7 ||1.4 ||61.7 ||0.65 ||0.23|
|Pods, Niger || ||14.3 ||24.7 ||6.3 ||1.5 ||53.2 ||1.11 ||0.14|
Bark contains 228% tannin, the fruit 513%.
A large thorny tree up to 20 m high and >2 m in diameter; bole forming up to
1/3 of height of tree; bark dull grey, fissured when old, crown dense; tree
puts out leaves during dry season and sheds them during rains; branchlets light
grey, spiny only at nodes, spines straight, up to 1 in. long; leaves pale and
glaucous, bluish grey, glabrous or pubescent, 2-pinnate, 9 to numerous pairs of
pinnae, cup-like glands on rachis, each pinna with 12 or more pairs of
leaflets, leaflets oblong, up to 1 cm long, hairy, unequal at base; flowers
(Jan., Apr., Nov.) in yellow spikes 1012.5 cm long; fruits (Jan., May, Nov.)
bright yellowish green when dry, up to 1215 x 4 cm, slightly curved, ends
rounded (Irvine, 1961).
Reported from the African Center of Diversity, the Ana Tree, or cvs thereof, is
reported to tolerate poor soil, drought, savanna, and some waterlogging (VITA, 1977). Back in 1978, when Senegalese farmers wanted seedlings, none were available. There is great variability in the morphology and pod yields.
Selection of wild plants for pod yield and/or fast growth would be a worthwhile contribution to arid developing countries. (2n = 26)
Native to the Transvaal and Southwest Africa, through West and North Africa to
Egypt, East Africa.
Probably ranging from Tropical Thorn to Subtropical Moist Forest Life Zones,
the Ana Tree is reported to tolerate annual precipitation of 3 to 6dm. Irvine
(1961) describes it as the largest thorn tree in Savanna Forest, especially in
inhabited areas; often left untouched, sometimes gregarious. In more mesic
Sahelian regions (400600 mm/yr), yields of millet, peanuts, and sorghum are
increased from ca 500 to ca 900 kg/ha/yr by growing under the canopy of
Acacia albida (Felker, 1978). Does best in sandy soils, growing well
where millet grows. Though faring best on sandy soils, it will tolerate
heavier soils with some waterlogging.
As late as 1978, techniques for establishing new seedlings had not been worked
out, according to Felker (1978). Seeds devoid of bruchid holes should be
scarified and started in deep containers to accomodate development of the tap
root. Good-sized plants develop in 1014 weeks, but frequent root pruning is
advised. Transplants from the wild are usually unsuccessful because of the
long tap root. VITA (1977) has a novel approach, feeding the seed to
livestock, which then graze the desired areas, eliminating seeds with their
manure. Nursery plantings, spaced at 10 x 10 m may require watering at first,
and protection from grazing animals for 58 years.
Peasants gather pods to feed to their cattle, or lop the foliage in the dry
season, when most other trees are leafless.
According to FAO (1980) a full grown tree can produce more than 100 kg pod/yr.
Felker (1978) notes that pod yields range from 6135 kg/tree. Some scientists
believe that yields could be managed to a much higher level than those of the
grasses and annual crops grown under the tree. Trees have reached 2 to 4 m
after only 3 or 4 years growth.
Related species such as Acacia tortilis have been reported to yield
giraffe forage to the tune of 5 MT/ha/yr. Yield increases under Acacia
albida correlate with a several fold increase in soil N and organic matter,
coupled with improved soil water-holding capacity. Acacia albida has
been shown to nodulate and reduce acetylene. While Acacias cannot be
recommended for cold and/or humid or everwet climates, they are suggested by
the NAS (1980a) as firewood sources in developing countries. Among the species
they consider are Acacia arabica, auriculiformis, brachystachya,
cambagei, cyanophylla, cyclops, dealbata, decurrens, ehrenbergiana, fistula,
heteracantha, holosericea, lysiophloia, mangium, mearnsii, mollissima,
nilotica, nubica, raddiana, saligna, senegal, seyal, spirocarpa, tortilis,
and verek. The Ana Tree was not recommended for firewood.
Caterpillars, locusts, and grazing animals may destroy the seedlings.
FAO Handbooks in Press (FAO, 1982)
| || ||Digestibility|
| ||Animal ||CP ||CF ||EE ||NFE ||ME|
|Pods ||Cattle ||51.0 ||16.5 ||71.4 ||74.8 ||2.09|
1. Taxonomy of Acacia spp.
2.Seed Collection, Handling, Storage and Treatment of Acacia spp.
3. Seed Insects in Acacia spp.
Complete list of references for Duke, Handbook of Energy Crops
- FAO. 1980a. 1979. Production yearbook. vol. 33. FAO, Rome.
- Felker, P. 1981. Uses of tree legumes in semiarid regions. Econ. Bot. 35(2):174186.
- Felker, P. 1978. State of the art: Acacia albida as a complementary intercrop with annual crops. USAID Information Services. Washington.
- Gohl, B. 1981. Tropical feeds. Feed information summaries and nutritive values. FAO Animal Production and Health Series 12. FAO, Rome.
- Irvine, F.R. 1961. Woody plants of Ghana. Oxford University Press. London.
- N.A.S. 1980a. Firewood crops. Shrub and tree species for energy production. National Academy of Sciences, Washington, DC.
- VITA. 1977. Reforestation in arid lands. VITA Publications. Manual Series 37E.
- Watt, J.M. and Breyer-Brandwijk, M.G. 1962. The medicinal and poisonous plants of southern and eastern Africa. 2nd ed. E.&S. Livingstone, Ltd., Edinburgh and London.
Last update November 10, 1997