Botany

Spirostachys Uncovered: An eco-physiological investigation of tamboti, Spirostachys africana

Tamboti, Spirostachys africana, is an indigenous tree to African savannas and generally occurs from Tanzania in the north to KwaZulu-Natal, South Africa in the south. Tamboti prefers poor drained clayey soils and can usually be found along watercourses in the bushveld areas. Tamboti belongs to the plant family Euphorbiaceae and is thus regarded an unpalatable somewhat poisonous plant.

One reason is the presence of latex, a white sticky and toxic substance produced by this tree. Although tamboti has an exceptional high economic value as forage (browsing) and furniture (wood), the latex is highly toxic. Direct contact with eyes or skin should be avoided. Concoctions made from the bark is known to be used for medicinal purposes by the local people, but it is also common knowledge that the smoke derived from a tamboti wood fire when inhaled or consumed via barbequed meat could be lethal.

The main objective of this project is to investigate the possible allelopathic effect of tamboti on its immediate environment, the severity of its latex and whether this toxic substance could change the chemical composition of the soil by means of germination trials and laboratory testing. Germination potential and inhibition of seedling growth will be investigated testing root, leaf and bark extracts prepared at different ethanol concentrations. Soil samples for seedling emergence will be collected during fieldwork. Bioassays testing for tannins, alkaloids and phenolics will also be performed.

Participants

• Ms. Lizandé Kellerman
• Angelique Joubert