Tree of the Year 2007

©Geoff Nichols

To the gardener who likes variety in the garden, Rhus pyroides should not be left out. This is a good species to provide textural variation in your garden. You will not be alone in choosing this tree as it has been chosen as the Tree of the Year for 2007 together with Pavetta schumanniana.

Description
This is a deciduous shrub or a small to medium-sized, multistemmed tree, frequently with spines. The bark is rough and grey. The leaves are compound, composed of three leaflets (tri-foliate). The leaves are borne on slender stalks, which are furrowed above. The leaflets are oval, narrowing at both ends, sometimes with a short tip. The largest leaflets are up to 70 x 30 mm with a round or a flat tip. They are smooth or velvety above, the lower surface is usually slightly hairy. The midrib and the secondary veins are conspicuous and raised below.

The flowers are inconspicuous and greenish in branched bunches in the axils of the leaves and at the end of the branches.

The fruits ripen in summer to late autumn. They are borne in such quantities that the branches bend with the weight. The fruits are round and small, white and red when ripe.

©Geoff Nichols

Conservation status
It is not protected by any legislation.

Distribution
Rhus pyroides is widely distributed all over South Africa and beyond the borders to Botswana and Namibia. It grows along rivers, on ironstone hills, in open bush, on forest verges, in valleys and in open grassland.

Derivation of name and historical aspects
Rhus pyroides was first collected by Burchell on the Asbestos Mountains in the Northern Cape. His specimen is still preserved at the Royal Botanic Gardens, Kew in London. The genus name Rhus is from the Greek word which means red and refers to the red autumn leaves in many species, or young red leaves of the other species. The specific epithet pyroides is from the Greek word, pyros, meaning fire and refers to the burning sensation caused by a prick from the thorns. According to Dr Robert Archer, this tree, along with the other Rhus species in South Africa, will form part of a separate genus Searsia, in the near future.

The Anacardiaceae family is widespread in warmer parts of the world. It consists of 60 genera and more than 500 species. In South Africa about 10 genera and more than 50 species are found.

Ecology
Rhus pyroides is ecologically important in South Africa as are many other species in this genus. As it is found in many vegetation types, it plays a role as a pioneer species in the cycle of plant succession. Birds are particularly fond of the fruits. Wattled Starling and Red-eyed Bulbuls have been seen gorging on them. Elephant, impala and kudu eat shoots and young leaves.

Uses and cultural aspects
The wood is used to make hoe handles. The branches are used to build kraals. The fruit is edible, with a pleasant, sweet-acidic taste. As herdboys we used to enjoy fruit from the wild, among those were Rhus pyroides, Scolopia mundii, Grewia occidentalis and Ziziphus mucronata.

This is a wonderfully decorative tree in a garden. It can also be used as a hedge.

Growing Rhus pyroides

 Rhus pyroides is not yet popular as a garden plant and needs to be promoted in the gardening fraternity. The male and female flowers are produced from different plants. According to Ernst van Jaarsveld, Kirstenbosch horticulturist, this tree is easily grown from seed. Sow the seeds in a well-balanced soil mix and they will germinate in three weeks. Seeds are not susceptible to any fungal infection. It is a hardy, frost-resistant plant and is well suited to highveld gardens. This is a bushy plant that takes pruning well when treated as a shrub.

References and further reading

• Palmer, E. & Pitman, N. 1972. Trees of southern Africa. Balkema, Cape Town.
• Moffett, R.O. 1993. Rhus. Anacardiaceae. Flora of southern Africa 19, part 3, fasc. 1. National Botanical Institute, Pretoria.
• Van Wyk, A.E. (Braam) & Van Wyk, P. 1997. Field guide to trees of southern Africa. Struik, Cape Town