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Acacia karroo (sweet thorn)

The fast-growing sweet thorn, with its striking yellow pompom-like flowerheads, is perhaps the most well-used acacia in southern Africa.
Acacia karroo in Zimbabwe

Acacia karroo in Zimbabwe (Photo: Richard Barnes)

Species information

Common name: 

sweet thorn, Karroo thorn, mimosa thorn, cockspur thorn, Cape gum (English); soetdoring, doorn boom (Afrikaans)

Conservation status: 

Rated by the IUCN as of Least Concern (LC).

Habitat: 

Woodlands and bushland, on clay and loam soils. Also found in desert and on coastal sand dunes.

Known hazards: 

The long thorns can cause injury to humans and animals, and can puncture vehicle tyres.

Taxonomy

Subclass: 
Superorder: 
Rosanae
Order: 
Fabales
Family: 
Leguminosae/ Fabaceae - Mimosoideae
Genus: Acacia

About this species

Acacia karroo is one of the fastest-growing acacias, and produces high-density wood (800-890 kg/m³). It is named after the Karoo region of the former Cape Province of South Africa, where it is common, and often the only tree found. The common name sweet thorn possibly refers to the sweet smell of the flowers, or to the fact that the presence of the species often indicates sweetveld (an area of vegetation that is good for grazing). Acacia karroo grows on deep, blackish nutrient-rich clay soils, and not on sand, and because of this association it is regarded as an indicator of good agricultural soils and rangeland.

Genus: 
Acacia

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