Vachellia is a genus of flowering plants in the legume family, Fabaceae, commonly known as thorn trees or acacias. It belongs to the subfamily Mimosoideae. Its species were considered members of genus Acacia until 2009. Vachellia can be distinguished from other acacias by its capitate inflorescences and spinescent stipules. Before discovery of the New World, Europeans in the Mediterranean region were familiar with several species of Vachellia, which they used as medicine. European names for them were inherited from the Greeks and Romans.
The wide-ranging genus occurs in a variety of open, tropical to subtropical habitats, and is locally dominant. In parts of Africa, Vachellia species are shaped progressively by grazing animals of increasing size and height, such as gazelle, gerenuk, and giraffe. The genus in Africa has developed thorns to defend against being eaten.
Nomenclature By 2005, taxonomists had decided that Acacia sensu lato should be split into at least five separate genera. The ICN dictated that under these circumstances, the name of Acacia should remain with the original type, which was Acacia nilotica. However, that year the General Committee of the IBC decided that Acacia should be given a new type (Acacia penninervis) so that the ~920 species of Australian acacias would not need to be renamed Racosperma. This decision was opposed by 54.9% or 247 representatives at its 2005 congress, while 45.1% or 203 votes were cast in favor. However, since a 60% vote was required to override the committee, the decision was carried, and a nom. cons. propositum was listed in Appendix III (p. 286). The 2011 congress voted 373 to 172 to uphold the 2005 decision, which means that the name Acacia and a new type follow the majority of the species in Acacia sensu lato, rather than this genus. The decision remained controversial following the 2011 Congress.
Description The members of Vachellia are trees or shrubs, sometimes climbing, and are always armed. Younger plants, especially, are armed with spines which are modified stipules, situated near the leaf bases. Some (cf. V. tortilis, , V. luederitzii and V. reficiens) are also armed with paired, recurved prickles (in addition to the spines). The leaves are alternate and bipinnately arranged, and their pinnae are usually opposite. The racemose inflorescences usually grow from the leaf axils. The yellow or creamy white flowers are produced in spherical heads, or seldom in elongate spikes, which is the general rule in the related genus Senegalia. The flowers are typically bisexual with numerous stamens, but unisexual flowers have been noted in V. nilotica (cf. Sinha, 1971). The calyx and corolla are usually 4 to 5-lobed. Glands are usually present on the rachis and the upper side of the petiole. The seed pod may be straight, curved or curled, and either dehiscent or indehiscent.
Habitat and Distribution It is widespread in the Arava desert area shared by Israel and Jordan.They are among the few trees native to the area. Other species of acacia are native to a variety of locales in the Americas, such as the southeastern USA, Mexico, Central and South America. It is also common in African countries such as South Africa, Angola, and Zambia. It also exists in India and Pakistan.
Practical Use and Consumption Vachellia seyal, a vachellia which grows in sub-Saharan Africa, secretes gum arabic, which has been used for thousands of years as a binder for paint. Gum arabic also became integral to the printing industry and lithography, and the advent of photography. It is also used in beverage and food domain, preventing crystallization, and in the medical sector, in the production of vitamins and medication.
In the Sahelian acacia savanna, the plant provides shelter and cooling cover to both humans and animals, as well as fuel, fiber, and material for fencing. It also balances the soil, and is a food for both wildlife and livestock. The tannins of the tree are used in the local leather tanning industry.
Vachellia tortilis are well known as acacia in Israel, where the seeds are perforated by seed-beetles, which consume the interior of the seed. The seeds then pass through the intestinal tracts of a variety of both domestic and wild animals, such as goats, ibex, gazelles, and hyrax, where they sometimes germinate. While in the digestive system, the beetles often expire. Seeds which endure may germinate if there is sufficient rainfall.
Species list 157 species are assigned to Vachellia as of June 2026.
52 are native to the Americas, 83 to Africa, Madagascar and the Mascarene Islands, 32 to Asia and 9 to Australia and the Pacific Islands.
Vachellia comprises the following species:
Vachellia abyssinica (Hochst. ex. Benth.) Kyal. & Boatwr.—flat top acacia subsp. abyssinica (Hochst. ex. Benth.) Kyal. & Boatwr. subsp. calophylla (Brenan) Kyal. & Boatwr. Vachellia acuifera (Benth.) Seigler & Ebinger—Bahama acacia, cassip, pork-and-doughboy, (Bahamas) rosewood Vachellia albicorticata (Burkart) Seigler & Ebinger Vachellia allenii (D. H. Janzen) Seigler & Ebinger—Allen acacia Vachellia amythethophylla (Steud. ex A.Rich.) Kyal. & Boatwr. Vachellia ancistroclada (Brenan) Kyal. & Boatwr. Vachellia anegadensis (Britton) Seigler & Ebinger—Anegada acacia, blackbrush-wattle, pokemeboy Vachellia antunesii (Harms) Kyal. & Boatwr. Vachellia arenaria (Schinz) Kyal. & Boatwr.—sand acacia Vachellia aroma (Gillies ex Hook. & Arn.) Seigler & Ebinger var. aroma Gillies ex Hook. & Arn. var. huarango Ruíz & J.Macbr. Vachellia astringens (Gillies in Hook. et Arn.) Speg. Vachellia azuana R.G.García, Clase, Ebinger & Seigler
Vachellia baessleri Clarke, Siegler & Ebinger Vachellia barahonensis (Urb. & Ekman) Seigler & Ebinger Vachellia bavazzanoi (Pichi-Sermolli) Kyal. & Boatwr. Vachellia belairioides (Urb.) Seigler & Ebinger—Bellair acacia Vachellia bellula (Drake) Boatwr. Vachellia biaciculata (S. Watson) Seigler & Ebinger Vachellia bidwillii (Benth.) Kodela—corkwood wattle, dogwood. "'Waneu', of the aboriginals of Central Queensland; 'Yadthor', of those of the Cloncurry River, Northern Queensland." Vachellia bilimekii (J. Macbr.) Seigler & Ebinger Vachellia bolei (R.P. Subhedar) Ragupathy, Seigler, Ebinger & Maslin Vachellia borleae (Burtt Davy) Kyal. & Boatwr.—sticky acacia, named for the collector Jeanne M. Borle. Vachellia brandegeana (I. M. Johnst.) Seigler & Ebinger—Baja California acacia Vachellia bravoensis (Isely) Seigler & Ebinger Vachellia bucheri (Marie-Victorín) Seigler & Ebinger—Bucher acacia Vachellia bullockii (Brenan) Kyal. & Boatwr. var. bullockii (Brenan) Kyal. & Boatwr. var. induta (Brenan) Kyal. & Boatwr. Vachellia burttii (Bak. f.) Kyal. & Boatwr. Vachellia bussei (Harms ex Sjöstedt) Kyal. & Boatwr. Vachellia californica (Brandegee) Seigler & Ebinger Vachellia campechiana (Mill.) Seigler & Ebinger—boatthorn acacia, spoon-thorn acacia f. campechiana (Mill.) Seigler & Ebinger f. houghii (Britton & Rose) Seigler & Ebinger Vachellia caurina (Barneby & Zanoni) Seigler & Ebinger Vachellia caven (Molina) Seigler & Ebinger var. caven (Molina) Seigler & Ebinger var. dehiscens (Ciald.) Seigler & Ebinger var. microcarpa (Speg.) Seigler & Ebinger var. stenocarpa (Speg.) Seigler & Ebinger Vachellia cernua (Thulin & Hassan) Kyal. & Boatwr. Vachellia chiapensis (Saff.) Seigler & Ebinger—Chiapas acacia Vachellia choriophylla (Benth.) Seigler & Ebinger—cinnecord acacia, Florida acacia, (Bahamas) cinnecord Vachellia clarksoniana (Pedley) Kodela Vachellia collinsii (Saff.) Seigler & Ebinger—Collins acacia Vachellia constricta (Benth.) Seigler & Ebinger—Whitethorn acacia, Mescat acacia Vachellia cookii (Saff.) Seigler & Ebinger—Cook acacia, cockspur acacia Vachellia cornigera (L.) Seigler & Ebinger—bullhorn wattle, bull's-horn acacia, bull-horn thorn, oxhorn acacia Vachellia cucuyo (Barneby & Zanoni) Seigler & Ebinger—Cucuyo acacia Vachellia cupeyensis (León) García-Beltrán Vachellia curvifructa (Burkart) Seigler & Ebinger Vachellia daemon (Ekman & Urb.) Seigler & Ebinger—Camagüey acacia Vachellia davyi (N.E.Br.) Kyal. & Boatwr.—corky-bark acacia
Vachellia ditricha (Pedley) Kodela Vachellia dolichocephala (Harms) Kyal. & Boatwr. Vachellia douglasica (Pedley) Kodela Vachellia drepanolobium (Harms ex Sjöstedt) P.J.H. Hurter—whistling thorn Vachellia dyeri (P.P.Swartz) Kyal. & Boatwr. Vachellia eburnea (L.f.) P. Hurter & Mabb. Vachellia ebutsiniorum (P.J.H. Hurter) Kyal. & Boatwr.—Ebutsini acacia Vachellia edgeworthii (T.Anders.) Kyal. & Boatwr. Vachellia elatior (Brenan) Kyal. & Boatwr. subsp. elatior (Brenan) Kyal. & Boatwr. subsp. turkanae (Brenan) Kyal. & Boatwr. Vachellia erioloba (E.Mey.) P.J.H. Hurter—camel thorn (Kameeldoring) Vachellia erythrophloea (Brenan) Kyal. & Boatwr. Vachellia etbaica (Schweinf.) Kyal. & Boatwr.—savannah thorn subsp. australis (Brenan) Kyal. & Boatwr. subsp. etbaica (Schweinf.) Kyal. & Boatwr. subsp. platycarpa (Brenan) Kyal. & Boatwr. subsp. uncinata (Brenan) Kyal. & Boatwr. Vachellia exuvialis (Verdoorn) Kyal. & Boatwr.—flaky-bark acacia Vachellia farnesiana (L.) Wight & Arn.—huisache var. farnesiana (L.) Wight & Arn. var. guanacastensis (H.D.Clarke et al.) Wight & Arn. var. minuta (M.E.Jones) Wight & Arn. var. pinetorum (F.J.Herm.) Wight & Arn.—pineland wattle Vachellia fischeri (Harms) Kyal. & Boatwr.—flat-topped thorn Vachellia flava (Forssk.) Kyal. & Boatwr. Vachellia flexuosa (Humb. & Bonpl. ex Willd.) Forero & C.Romero Vachellia gentlei (Standley) Seigler & Ebinger—gentle acacia Vachellia gerrardi (Benth.) P.J.H. Hurter—red acacia var. calvescens (Brenan) P.J.H. Hurter var. gerrardi (Benth.) P.J.H. Hurter var. latisiliqua (Brenan) P.J.H. Hurter Vachellia glandulifera (S. Watson) Seigler & Ebinger Vachellia globulifera (Saff.) Seigler & Ebinger—globular acacia Vachellia grandicornuta (Gerstner) Seigler & Ebinger—horned-thorn acacia Vachellia guanacastensis (Clark, Seigler, & Ebinger) Seigler & Ebinger Vachellia gummifera (Willd.) Kyal. & Boatwr.—gum-bearing acacia Vachellia haematoxylon (Willd.) Seigler & Ebinger—gray camel thorn, giraffe thorn Vachellia harala Thulin & Gifri Vachellia harmandiana (Pierre) Maslin, Seigler & Ebinger Vachellia hebeclada (DC.) Kyal. & Boatwr.—candle-pod acacia subsp. chobiensis (O.B.Miller) Kyal. & Boatwr. subsp. hebeclada (DC.) Kyal. & Boatwr. subsp. tristis (A.Schreiber) Kyal. & Boatwr. Vachellia hindsii (Benth.) Seigler & Ebinger—Hinds acacia Vachellia hockii (De Wild.) Seigler & Ebinger Vachellia horrida (L.) Kyal. & Boatwr.—long white-galled acacia subsp. benadirensis (Chiov.) Kyal. & Boatwr. subsp. horrida (L.) Kyal. & Boatwr. Vachellia hunteri Oliv. Vachellia inopinata (Prain) Maslin, Seigler & Ebinger Vachellia insulae-iacobi (L. Riley) Seigler & Ebinger
Vachellia jacquemontii (Benth.) ali—baonḷī, raati-banwali Vachellia janzenii (Ebinger & Seigler) Seigler & Ebinger—Janzen acacia Vachellia johnwoodii Boulos Vachellia karroo (Hayne) Banfi & Galasso—Karroo BushTaxon in the V. karroo complex, see: Vachellia kingii (Prain) Maslin, Seigler & Ebinger Vachellia kirkii (Oliv.) Kyal. & Boatwr.—flood plain acacia subsp. kirkii (Oliv.) Kyal. & Boatwr. var. kirkii (Oliv.) Kyal. & Boatwr. var. sublaevis (Brenan) Kyal. & Boatwr. subsp. mildbraedii (Harms) Kyal. & Boatwr. Vachellia koltermanii R. García, M. Mejía, Ebinger, & Seigler Vachellia kosiensis (P.P.Sw. ex Coates Palgr.) Kyal. & Boatwr.—dune acacia, dune sweet-thorn Vachellia lahai (Steud. & Hochst. ex. Benth.) Kyal. & Boatwr.—red-thorn acacia Vachellia lasiopetala (Oliv.) Kyal. & Boatwr. Vachellia latispina (J.E.Burrows & S.M.Burrows) Kyal. & Boatwr. Vachellia leucophloea (Roxb.) Maslin, Seigler & Ebinger—pilang var. leucophloea (Roxb.) Maslin, Seigler & Ebinger var. microcephala (Kurz) Maslin, Seigler & Ebinger Vachellia leucospira (Brenan) Kyal. & Boatwr.