Common Name(s): Karroo, Karroo Thorn, Sweet Thorn

Synonym(s):

Family: Fabaceae

Native To: Cape Province, Angola, Zambia, Zimbabwe, and Mozambique.

Native Habitat: Coastal areas and river beds of southern Africa.

Growth Habit: Acacia karoo grows in several forms or habits - from multi stemmed shrubs to low thickets, to taller trees.

Flowering: Mid Spring

Distinguishing Characteristics: Sweet Thorn’s leaves resemble a mesquite’s - dark leathery green, doubly compound, with up to 20 sets of leaflets containing pinnae about a half of an inch long. Flowers are brilliant yellow pompons, typical of many acacias, held in clusters of 4 to 6, and are sweetly scented. The killer spines, which are a striking feature of Acacia karroo, are modified stipules that can reach to 3 inches long. They are held in pairs, at nearly right angles to the branch.

Natural History and Cultivation Notes: The flowers are said to attract larvae and adults of several butterfly species, as well as other insects. Birds (going after the insects) nest in the canopy, taking advantage of the long white spines that give protection against predators.

Ethnobotany: Traditional uses in the southern part of Africa have developed over many decades, both by native cultures and the colonizers. The red and shaggy bark can be made into rope or used for tanning leather. The wood is extremely hard and useful for woodworking and firewood. Stock and game also feed on the leaves, flowers and pods. Honey made from the nectar is mild and sweet. Medicinal uses include wound poultices, cold remedies and more. The dried leaves are said to have antibacterial and antioxidant activity. In addition, early naturalists were known to have used the long spines to pin the exotic insects they had collected!

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