Warburgia salutaris (SA Tree List No. 488), the pepper-bark tree, rarely reaches 20 m. This will only happen in favourable circumstances such as those moist, wooded, rocky ravines where all trees compete hard for sunlight. The typical height of this slender forest and bushveld tree is only 5 m to 10 m. The tree grows in north-eastern South Africa and beyond the northern border as far as Malawi and Zambia.
The bark of the pepper-bark tree is brown, dark brown and rough. The young twigs are long and lax with lenticels. Much of the tree is aromatic.
The leaves are simple, spirally arranged and crowded at branch ends. Leaf shape is lanceolate to elliptic with entire margins and a petiole of up to 5 mm long. Leaf tips and bases taper. The leaf colour is bluish when young, becoming dark green and glossy on top later, paler below. The midrib is often slightly off-centre, the veining inconspicuous and there are many gland dots. Leaves often curve downwards at the margins, upwards along the pale midribs.
The flowers are small and solitary. Flower colour is white or greenish white. The corolla consists of ten rounded petals in 2 concentric whorls. The oval to globose pale green berry that follows can be seen in this photo. The skin is leathery, covered in scattered glands. The fruit becomes purple when ripe.
The inner bark of Warburgia salutaris tastes bitter and peppery, giving cause to the common name. How did this become well-known? Various bits of this tree have been ingested by people in some form as concocted medicines since times immemorial. Results have continually favoured furtherance of such practices. This traditional panacea is still significant in modern medicine, but self-treatment or lay experimentation must always be discouraged. The medicinal status of the tree is reflected in the specific adjective, salutaris (health giving). The leaves also exude a peppery smell when crushed.
Plant this tree! has been common advice to gardeners for countering tree destruction caused by excessive muti harvesting. A cultivation project exists in KwaZulu-Natal for the tree to ensure survival (Coates Palgrave, 2002; Venter, et al, 1996; Van Wyk and Gericke, 2000; Schmidt, et al, 2002).