Origin and Habitat: It is the the principal tree euphorbia of northeast Africa ranging from East Sudan (Red Sea Hills) to Eritrea, Northern Ethiopia and Northern Somalia.
Habitat: Grows in the most exposed places in well-drained stony soils and in the crevices of rock faces of hills and slopes, in montane dry deciduous and evergreen woodland and bushland , woodland and shrub savanna at 850 to 2200 m altitude. It occurs widely throughout dryland Africa and it is often dominant.

• Euphorbia abyssinica J.F.Gmel.
• Euphorbia abyssinica var. tetragona Schweinf.

• Euphorbia abyssinica J.F.Gmel.
• Euphorbia abyssinica var. tetragona Schweinf.
• Euphorbia acrurensis N.E.Br.
• Euphorbia aethiopum Croizat
• Euphorbia controversa N.E.Br.
• Euphorbia disclusa N.E.Br.
• Euphorbia erythraeae (A.Berger) N.E.Br.
• Euphorbia abyssinica var. erythraeae A.Berger
• Euphorbia candelabrum var. erythraeae. A.Berger
• Euphorbia grandis Lem.
• Euphorbia hararensis Pax
• Euphorbia neglecta N.E.Br.
• Euphorbia neutra A.Berger
• Euphorbia obovalifolia A.Rich.
• Euphorbia officinarum var. kolquall Willd.
• Euphorbia richardiana Baill.

Description: Euphorbia abyssinicaSN|1958]]SN|1958]] is a nice large, cactus-like, candlestick, tree Euphorbia with short thorns. It form a dense crown of ascending branches usually up to 4,5 m tall (but reported to reach 9 or more metres of height). E. abyssinica is a highly variable species with several forms and making precise descriptions may be difficult.
Stems: Columnar, angular branches, 4-12 cm wide, constricted into ovate segment appox 15 cm long,
Ribs: Usually 4 (but up to 8 in juvenile speciemens) very deep, vertical or slightly twisted with thin walls and shallow sinuate teeth up to12 mm apart.
Spines: Spine Shields triangular, about 10 x 7 mm wide, separate or closely packed (almost touching) on the rib border, becoming corky. Spines in pairs, stout 2-10 mm long.
Leaves: Ovate lanceolate, 2-5 cm long only on new growth at stems tips.
Flowers: Cymes, simple 1 to 5 together. Cyathia 8-12 mm wide, peduncles up to 5 mm long stout, nectar glands elliptic yellow, almost touching.
Fruits: Capsules about 12 x 15(-25) mm wide, subglobose, fleshy, white turning red, hardening brown, becoming deeply 3-lobed at maturity before dehiscence.
Seeds: Smooth, subglobose, 4,5 x 3,5 mm wide.
Remarks: It has a very clean and neat appearance and is often confused with with Euphorbia ammak, Euphorbia ingensSN|27231]]SN|27231]] and Euphorbia erythrae. Nevertheless this plant is often leafed out, especially if warm and given plenty of water. This makes it easy to tell from , which rarely has leaves, or they are so small and insignificant. Furthermore Euphorbia abyssinicaSN|1958]]SN|1958]] grows more vertical in form than its cousins.

Bibliography: Major references and further lectures
1) Urs Eggli “Illustrated Handbook of Succulent Plants: Dicotyledons” Volume 2. Springer, 2002
2) Hermann Jacobsen “A handbook of succulent plants: descriptions, synonyms, and cultural details for succulents other than Cactaceae” Volume 1 Blandford Press, 1960
3) Anthony Huxley, Mark Griffiths, Margot Levy “The New RHS Dictionary of Gardening” Macmillan Publishers Limited, 1992
4) Alfred Byrd Graf “Exotica, series 4 international: pictorial cyclopedia of exotic plants from tropical and near-tropic regions” Roehrs Co. Publishers, 1985

Cultivation and Propagation: It is an easy species to grow that is suited for any well drained soil in full sun. But young plant are happy growing indoors, where they can easily reach the ceiling.
Growing rate: It is a moderately fast grower, and will quickly become large landscape masterpieces in just 3-5 years.
Soil and pots: Give the plant an airy growing medium which mainly consists of non organic material such us clay, pumice, lava grit, and only a little peat or leaf-mould. If plant becomes very red, this is a sign that the roots have not developed properly, so repot the plant with fresh growing medium. Like quite small pots, repott in very later winter, early spring. It will be content in its position and with its soil for years.
Watering: Water regularly during the active growing season from March to September. No water should ever be allowed to stand around the roots. Keep almost completely dry in winter.
Fertilization: Need a perfect fertilizer diet in summer. Use preferably a cacti and succulents fertilizer with high potassium content including all micro nutrients and trace elements or slow release fertilizer.
Wing tolerance: Only downside is from strong winds, the columns often smash into each other, causing permanent scarring... best to plant in such a location where winds are not a big issue.
Exposure: It can tolerate moderate shade, and a plant that has been growing in shade should be slowly hardened off before placing it in full sun as the plant will be severely scorched if moved too suddenly from shade into sun.
Maintenance: Can be pruned for shape and branching.
Hardiness: Frost tender, frost free zones only. It is definitely more tender than Euphorbia ammakSN|1958]]SN|18545]] or Euphorbia ingensSN|27231]]SN|27231]]
Warning: All Euphorbias contain a white sap that can be irritating to eyes and mucous membranes. If contact is made with this white sap, take care to not touch face or eyes before washing hands with soap and water.
Gardening: This tree can be grown in large, rocky, well-drained soil in gardens in drier areas. It is very drought resistant but susceptible to frost. It makes one of the better house plants for an Euphorbia, dealing well with low light situations (though recommend higher light if possible). Somewhat user-friendly with only sparse spines along the edges of the plant. Slightly delicate, though, and spines tear off easily, exposing that latexy sap. It is also appreciated as a live fence because it is easily propagated from untreated mature branch cuttings.
Fuel production: The Italians attempted to grow Euphorbia abyssinicaSN|18545]]SN|1958]] in 1935-36 to use its latex to produce a gasoline-like substitute.
Fishing: It is used to stupefy fish, making it possible to catch them by hand. The fish poison is prepared by soaking a bundle of grass in the latex, tying it to a stone and throwing it into the water. Paralysed fish rise to the surface within a short period of time.
Propagation: It is easy to propagate by cuttings in late spring to summer, just take a cutting of the plant let it dry for 1 or 2 weeks and stuff it in the ground (preferably dry, loose, extremely well draining soil). It is better to wash the cut to remove the latex. Place the cutting in a warm, bright and slightly humid spot, to increase the building of new roots.