Small Knobwood
Zanthoxylum capense
Flora
| At a Glance | |
| Family | Rutaceae |
| Seasonality | Deciduous |
| Height | 5m but can get to 15m in favourable conditions |
| SA Tree Number | 253 |
| Conservation Status | This is a protected tree in South Africa in terms of the National Forests Act no. 84 of 1998. |
Description
This is a single-stemmed tree which branches upwards to form a moderate, V-shaped canopy. The bark on young branches is smooth with straight dark brown thorns and light to dark grey on older branches and on stems with straight spines on scattered cone-shaped knobs.
It has glossy dark green leaves.
The most noticeable features of the small knobwood are the small cone like knobs all the way up the trunk of the tree
Distribution
The small knobwood is distributed from Zimbabwe in the north to the Western Cape in the south. It is mostly found in dry to evergreen woodland and on rocky hill slopes, but has adapted to a wide range of habitats.
Flower - Fruit
Inconspicuous, greenish-white, sweet-scented flowers grow in sprays at the end of the twigs. Similar male and female flowers are on separate trees (Oct –Feb) (20 – 60 mm).
The fruit is a round splitting capsule up to 5 mm in diameter, covered with glands, green, turning red when ripe, splitting later to reveal a single black, oil-rich seed per capsule.
Uses
An excellent garden tree which stands out.
Larvae of the following butterflies feed on the leaves of this tree: the citrus swallowtail (Papilio demodocus), the white-banded swallowtail (Papilio echeroides) and the emperor swallowtail (Papilio ophidicephalus).
The ripe fruits are eaten by vervet monkeys.
The leaves are browsed by grey duiker and the seeds are eaten by mousebirds and barbets.
The wood can be used to make pick handles, knobkieries, planks and yokes. The seeds are used to make perfume. A wide range of medicinal uses is recorded, and are used in traditional medicine.
Local Information
Not a very common tree and can be confused with the Forest Knobwood which is more common in the Kloof forests.
Interesting Facts
The leaves have a strong citrus smell when crushed.
Zanthoxylum is Greek, xanthos meaning ‘yellow', xylon meaning ‘wood'; capense means 'of the Cape'. Several species of this genus have yellow heartwood.