Vachellia cornigera       0

Its very fine foliage is dark green. It is carrying large bifid spines (such as 2 horns), they are positioned at the base of the leaf. They are first green, then shiny brown and finally gray-brown. The pods are 40 to 50mm long and 15mm thick. The seeds, when the pod reaches maturity, are surrounded by an abundant and edible pulp.

Unlike other Acacias, Bullhorn Acacias are deficient in the bitter alkaloids usually located in the leaves that defend against ravaging insects and animals. Bullhorn Acacia ants fulfil that role. In return, the tree feeds them thanks to the nodules rich in protein and lipid, contained in excrescences at the end of the petiole, as well as with the nectar rich in carbohydrate. This is called mutualism where one depends on the other and where the perfect symbiosis allows the survival of both.

It's highly sought after by collectors. It is found in moist or dry thickets, in plains and at a maximum altitude of 900m. It supports frost but not above -4°C. It prefers the full sun. It accepts any type of soil provided it is well drained.

References
- Developmental Aspects of the Shoot Apex, Leaf, and Beltian Bodies of Acacia cornigera, Fred R. Rickson. American Journal of Botany 1969 Vol. 56(2) pag. 195-200. DOI
- Recruitment Dynamics of Vachellia cornigera and Its Ant Occupants in Restored Tropical Forest, Anika Hazra. 2018. Link
- Taxonomic revision of the Ant-Acacias (Fabaceae, Mimosoideae, Acacia, Series Gummiferae) of the New World, Seigler, D. S., & Ebinger, J. E. Annals of the Missouri Botanical Garden 1995 Vol. 82(1) pag. 117–138. DOI

- Acacia (Leguminosae-Mimosoideae): A contribution to the flora of Central Australia, Maslin, BR. Journal of the Adelaide Botanic Garden 1980 pag. 301-321. JStor
- Conservation status revision and communities' perceptions of 22 Aloe species in Tanzania, Abihudi, Siri and de Boer, Hugo and Treydte, A.C. Plant Ecology and Evolution 2021 Vol. 154 pag. 391-404. DOI
- Flora of Southern Africa, L.E. Codd, B. De Winter And H.B. Rycroft. Vol. 16(1) pag. 1-155. Address
- New combinations in the genus Vachellia (Fabaceae: Mimosoideae) from Australia, Wilson, Peter. Telopea 2006 Vol. 11(2) pag. 233-244. DOI
- Phylogenetic position and revised classification of Acacia sl (Fabaceae: Mimosoideae) in Africa, including new combinations in Vachellia and Senegalia, Kyalangalilwa, Bruce and Boatwright, James S and Daru, Barnabas H and Maurin, Olivier and van der Bank, Michelle. Botanical Journal of the Linnean Society 2013 Vol. 172(4) pag. 500-523. Address
- Synoptic overview of exotic Acacia, Senegalia and Vachellia (Caesalpinioideae, mimosoid clade, Fabaceae) in Egypt, Hassan, Rania A and Hamdy, Rim S. Plants 2021 Vol. 10(7) pag. 1344. Address
- Taxonomic revision of South American Species of the Genus Acacia Subgenus Acacia (Fabaceae: Mimosoideae), Ebinger, John & Seigler, David & Clarke, H.. . Systemiiatic Botany 2009 Vol. 25(4) pag. 588-617. DOI
- Taxonomic studies on Sudan Acacias, Hamza Mohamed Elamiin. 1972. Address
- Trees of Southern Africa, Meg Coates Palgrave. 2002 pag. 264-272. ISBN
- World Wide Wattle, Boyce Thompson. 2020.
- A selection of Ethiopia’s indigenous trees: Biology, uses and propagation techniques, Negash, Legesse. 2022 pag. 22-42. ISBN
- Hommes et Plantes. Vol. 17 pag. 7-13. Address

Biological type: tree
Frost resistance: 50ºF
Leaf color: dark green
Flower color: pink
Reproduction mode: trimonoecious plant that bears hermaphroditic flowers, female flowers and male flowers on the same plant

Specifications for the Mediterranean basin
Adult size (h x w): 32,8ft x 26,2ft
Sun exposure: shadow (Sun hours: <3h
Foliage: evergreen
Growth: average
Flowering time from July until January

Specific information for our garden
Planting substrate: 20%Compost+40%Clay+40%Sand
Plant watering: 3x a week pH 6.5
Logical sequence of containers for: Eucalyptus; forestry plate, forestry pot 3L, Airpot 12L, Airpot 50L, Airpot 800L
Propagation is done by cuttings

Ecology in its country of origin
Rainfall: 1300-3000mm

SPRING Soak the seeds in warm water of 210,2°F for 12h. Sow the seeds at 5mm depth in the Well Drained Seed Sowing Mix between 64-72°F. During germination keep the substrate moist and in daylight. The seeds germinate in 2-3 weeks. The viability of the seeds, kept under good conditions, is 10 years.

Germination references
- Seeds: Ecology, Biogeography, and, Evolution of Dormancy and Germination, Baskin, Carol & Baskin, J.M. 2014 pag. 1-1586. DOI


Germination references for the genus
- A selection of Ethiopia’s indigenous trees: Biology, uses and propagation techniques, Negash, Legesse. 2022 pag. 22-42. ISBN
- USDA Forest Service's Woody Plant Seed Manual, John K. Francis and Craig D.Whitesell. 2008. Address


Cuttings instructions
Take the cuttings at the end of spring, soak them in a hormonal preparation for cuttings. Plant them in a substrate rich in perlite and keep them sufficiently moist in sealed freezer bags.