Vachellia karroo has olive-brown bark with white or beige lenticels on young stems (SA Tree List No. 172). On old trunks the bark becomes dark or red-brown, almost black and rough as in the picture.
The bark of this tree has been used in tanning, imparting a red colour to the leather. The inner bark was used to make ropes. The gum exuded from damage to the surface of the stem is yellow or red, edible and used in making confectionery and adhesives (Coates Palgrave, 2002).