General Info

Tree is usually up to 3m high. Trunk becomes deeply fissured. Stems have single spines. Simple Leaves are obovate. Whitish Flowers are pungent, dioecious and 5-merous. Fruit is a capsule.

Description

Gymnosporia buxifolia

Previous names: Maytenus heterophylla, Celastrus buxifolius, Gymnosporia condensata, Maytenus cymosa.

RSA Tree No. 399.

Family: Celastraceae. (Spike-thorn, Staff-tree and Bitter-sweet family). There are currently close to 100 genera and in excess of 1 300 species. The family has about 60 trees in southern Africa – including those in the genera Catha, Elaeodendron and Maytenus. This family has simple leaves. Flowers are usually small, actinomorphic (regular), bisexual or unisexual and sepals and petals are usually persistent. One or 2 Pollen sacs are present in each Anther which opens by longitudinal slits. The Ovary is usually superior and usually has 2-5 locules. The Style is usually thick and the Stigma has 2-5 lobes. Fruit varies.

Name derivation: Gymnosporia naked seeds – referring to the seeds that remain attached to the fruit after it has opened. buxifolia – variable leaves. There are about 30 species in the genus Gymnosporia in southern Africa.

Conservation Status: L C (Least Concern). 2009. (Raimondo et al.).

Tree

This evergreen Tree is usually up to 3m and occasionally up to 10m high. It is often a variable shrub. Bark on young branches is green and may become reddish. With age it becomes light brown and then darker brown and flaking. The Trunk eventually becomes deeply fissured and corky. The green terminal branches tend to droop. They age into being circular in cross-section. Branches have densely crowded branchlets or shoots of limited growth, in which the internodes elongate little or not at all, bearing reproductive structures and / or leaves. The branchlets may be thickened with insect galls. Smaller branches are reddish or light brown and terete (circular in cross-section). The stems have single, straight, sharp Spines that are up to 10cm long. These spines are associated with the leaves or flowers. These unpaired spines may be slender or thickened.

Leaves

The simple Leaves are obovate (the reverse of ovate, the terminal half is broader than the basal half), or narrowly obovate-lanceolate. They may be clustered or alternate in their arrangement on Brachyblasts (densely crowded branchlet or shoot of limited growth, in which the internodes elongate little or not at all, bearing reproductive structures and/or leaves). Size of leaves is variable and up to 8 x 2,5cm. The Apex is almost round to slightly notched. The Base tapers and the Midrib is indented above. The thinnish, hairless Blade is greyish green above and may be slightly lighter below. The Veins may be visible above and below. Towards the apex, the Margin becomes unevenly scalloped. The Petiole (leaf stalk) is up to 1cm long. Stipules (basal appendages of the petiole) are free, slender and taper to a point. Dead stipules may remain on the tree.

Flowers

The whitish Flowers are pungent – smelling of decaying meat and are up to 7mm in diameter. The plants are dioecious (having male and female parts on separate plants). They are located in an axillary position on dwarf spur branches and occur in dense clusters in a dichasium (cyme in which each flowering branch gives rise to two or more branches symmetrically placed). Flowers may also occur on the spines. Sepals are joined at the base and are imbricate (having regularly arranged, overlapping edges, as roof tiles or fish scales). There are 5 Petals. In the Male Flowers, the 5 Stamens arise at the base of the Disc (a more or less fleshy or elevated development of the receptacle) and alternate with the petals. A Pistillode (sterile pistil in male flowers) is present. In the Female Flower, there is a single Pistil (a unit of the Gynoecium, the female element of the flower, composed of the Ovary, Style and Stigma) and the superior Ovary is partially emerged in the disc. There are usually 3 Ovules in each of the Locules. The single Style is short. Staminodes (sterile stamens) are present. The flowers pollinated, include adult bluebottle flies (Calliphora vomitoria). The strong smell of the flowers attracts the flies. Flowering times vary in different areas. (Jun-Feb).

Fruit

The small, almost spherical, white to grey-brown, leathery Fruit is up to 5mm wide and wrinkled. It is a 3-valved and veined Capsule (a dry fruit resulting from the maturing of a compound ovary. This usually opens longitudinally at maturity by one or more lines of dehiscence). A yellow Aril (an appendage or outer covering of a seed and may appear as a pulpy covering) is present. It develops from a stalk, the funiculus, connecting an ovule or a seed with the placenta). This partially covers the up to 4 reddish brown glossy Seeds. These seeds remain attached to the fruit for some time. Birds disperse the seeds. (Aug-Apr).

Distribution & Ecology

These Trees commonly occur in open veld, on rocky outcrops and in dry and disturbed places. They may occur on the edges of forests, in wooded grasslands and may be associated with termites. This pioneer species is widespread in the RSA and Zimbabwe. The Fruit is eaten birds e.g. the Cape White-eye and are responsible for seed dispersal. Giraffe, nyala and kudu browse Leaves. Black Rhino consume the leaves and the Bark. This plant is located in all RSA provinces and is widespread in southern Africa. The plant is cold and drought resistant and can survive coastal conditions. The fact that the plant can also survive in dry and cold temperatures, enables it to be so widespread.

Ethnobotany

The Wood is hard, dense and strong but handling it can irritate the skin. The wood colour varies from almost white to yellow to brown or even pink. It is used for tool handles and, when big enough, is used for turning. It is also used for fuel. The Sap may be slightly toxic. The Fruit is edible. A planted hedge, with the spines makes an effective barrier. The smell of flowers can be unpleasant.

References

Boon, R. 2010. Pooley’s Trees of eastern South Africa. Flora and Fauna Publications Trust, Durban.

Coates Palgrave, M. 2002. Keith Coates Palgrave Trees of Southern Africa, edn 3. Struik, Cape Town.

Lawrence, G. H. M, 1951. Taxonomy of Vascular Plants, The Macmillan Company, New York. Tenth Printing 1965.

Palmer, E. & Pitman, N. 1972. Trees of southern Africa, Balkema, Amsterdam, Cape Town.

Schmidt, S. Lotter, M. & McCleland, W. 2002. Trees and Shrubs of Mpumalanga and the Kruger National Park.

van Wyk, B. & van Wyk, P. 1997 Field guide to Trees of Southern Africa, Struik, Cape Town.

 

http://redlist.sanbi.org/species.php?species=1883-5

http://pza.sanbi.org/gymnosporia-buxifolia

https://en.wikipedia.org/wiki/Gymnosporia_heterophylla

http://posa.sanbi.org/flora/browse.php?src=SP