Acacia nilotica (gum arabic tree,^[2] Babul/Kikar, Egyptian thorn, Sant tree, Al-sant or prickly acacia;^[3] called thorn mimosa or prickly acacia in Australia; lekkerruikpeul or scented thorn in South Africa) is a species of Acacia native to Africa, the Middle East and the Indian subcontinent. It is also currently an invasive species of significant concern in Australia.

The generic name of this plant derives from ακακία (akakia), the name given by early Greek botanist-physician Pedanius Dioscorides (ca. 40-90) to this tree as a medicinal, in his book Materia Medica.^[4] This name derives from the Greek word for its characteristic thorns, ακις (akis, thorn).^[5] The species name nilotica was given by Linnaeus from this tree's best-known range along the Nile river.

The plant A. nilotica then, in turn, became the type species for the Linnaean Acacia genus (not all of which have thorns, even though they are named for them). For the ongoing reclassification of this and other species historically classified under genus Acacia, see the list of Acacia species.

Description

Spring blossoms at Hodal in Faridabad District of Haryana, India

Acacia nilotica is a tree 5–20 m high with a dense spheric crown, stems and branches usually dark to black coloured, fissured bark, grey-pinkish slash, exuding a reddish low quality gum. The tree has thin, straight, light, grey spines in axillary pairs, usually in 3 to 12 pairs, 5 to 7.5 cm (3 in) long in young trees, mature trees commonly without thorns. The leaves are bipinnate, with 3-6 pairs of pinnulae and 10-30 pairs of leaflets each, tomentose, rachis with a gland at the bottom of the last pair of pinnulae. Flowers in globulous heads 1.2-1.5 cm in diameter of a bright golden-yellow color, set up either axillary or whorly on peduncles 2–3 cm long located at the end of the branches. Pods are strongly constricted, hairy, white-grey, thick and softly tomentose. Its seeds number approximately 8000/kg.^[6]

Distribution

Trunk at Hodal in Faridabad District of Haryana, India

Acacia nilotica is native from Egypt, across the Maghreb and Sahel, south to Mozambique and KwaZulu-Natal, South Africa, and east through Arabian Peninsula to Pakistan, India and Burma.^[7]

It has become widely naturalised outside its native range including Zanzibar and Australia. Acacia nilotica is spread by livestock.^[7]

Uses

Forage and fodder

In part of its range smallstock consume the pods and leaves, but elsewhere it is also very popular with cattle. Pods are used as a supplement to poultry rations in India. Dried pods are particularly sought out by animals on rangelands. In India branches are commonly lopped for fodder. Pods are best fed dry as a supplement, not as a green fodder.

Hedges

A. nilotica makes a good protective hedge because of its thorns.^[8]

Medicine

In Siddha medicine, A. niloticagum is used to treat otherwise watery semen.^{[9][unreliable medical source?]}

Lumber

The tree's wood is "very durable if water-seasoned" and its uses include tool handles and lumber for boats.^[8] The wood has a density of about 1170 kg/m³.^[10]

Propagation

There are 5000-16000 seeds/kg.^[11]

Subspecies

• Acacia nilotica subsp. adstringens (Schum. & Thonn.) Brenan^[10]
• Acacia nilotica subsp. cupressiformis
• Acacia nilotica subsp. hemispherica
• Acacia nilotica subsp. indica (Benth.) Brenan^[10]
• Acacia nilotica subsp. kraussiana (Benth.) Brenan^[10]
• Acacia nilotica subsp. leiocarpa Brenan^[10]
• Acacia nilotica subsp. nilotica
• Acacia nilotica subsp. subalata (Vatke) Brenan^[10]
• Acacia nilotica subsp. tomentosa (Benth.) Brenan^[10][12]

Seed pods

Compound leaf, seed, flower and seed pod

Bark structure

See also

• List of Indian timber trees

References

Wikimedia Commons has media related to: Acacia nilotica

Wikispecies has information related to: Acacia nilotica

1. ^ ILDIS LegumeWeb
2. ^ http://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=182086
3. ^ http://dictionary.infoplease.com/babul http://www.merriam-webster.com/dictionary/babul http://www.worldagroforestry.org/Sea/Products/AFDbases/AF/asp/SpeciesInfo.asp?SpID=81
4. ^ "Acacia nilotica (acacia)". Plants & Fungi. Royal Botanic Gardens, Kew. Archived from the original on 12 January 2010. Retrieved 2010-01-28. 
5. ^ Quattrocchi, Umberto (2000). CRC World Dictionary of Plant Names. 1 A-C. CRC Press. p. 6. ISBN 978-0-8493-2675-2. 
6. ^ Handbook on Seeds of Dry-zone Acacias FAO
7. ^ ^{a b} http://www.weeds.crc.org.au/documents/wmg_prickly_acacia.pdf
8. ^ ^{a b} Google Books Select Extra-tropical Plants Readily Eligible for Industrial Culture Or Naturalization By Ferdinand von Mueller
9. ^ Dr. J. Raamachandran, "HERBS OF SIDDHA MEDICINES - The First 3D Book on Herbs"
10. ^ ^{a b c d e f g} FAO
11. ^ Tropical Forages
12. ^ USDA Germplasm Resources Information Network (GRIN)