This small Tree has grey bark and may reach 7m high. The leathery compound Leaves are imparipinnate with up to 7 leaflets. The tiny, star-shaped, dioecious Flowers are in panicles. Fruit is a drupe.
Ekebergia pterophylla, Trichilia alata.
RSA Tree No. 299.
Common names: Rock Ash, Rock Cape Ash, Klip-essenhout, Basternieshout, Rots-essenhout.
Family: Meliaceae (Mahogany family). This family of shrubs and small trees has 50+ genera and 570+ species. Most members are trees or shrubs. Perhaps the best-known local alien tree in this family is the seringa (Melia azedarach). This tree is now considered invasive in the RSA. In southern Africa, there are about 6 genera and 11 species. Those genera with trees include Ekebergia, Nymania, Khaya and Trichilia. Most trees are evergreen and Leaves are large, simple or compound, lack stipules and are usually alternately arranged. They occur in a large cluster or on short shoots. The bisexual or unisexual Flowers are regular, axillary and solitary. The Calyx has 4-5 sepals, which are free to near the base. The 4 Petals are imbricate (having regularly arranged, overlapping edges). The 5 to many Stamens are free except at the base and the Anthers are attached in the middle. The superior Ovary has a simple Style, which ends in a disc-like, head-like or lobed Stigma. The Fruit is a capsule or a drupe and may be winged or have a pulpy covering.
Name derivation: Ekebergia was named after Captain C.G. Ekeberg (1716-1784). He made 10 voyages to East India and China and brought home important natural history collections. In 1762 Carl Linnaeus got a living tea plant from Captain C. G. Ekeberg and succeeded getting it to flower in the summer of 1765. pterophylla – winged leaf. Ekebergia capensis is a closely related but is a much larger tree.
Conservation Status: L C (Least Concern)
This evergreen Tree with its usually flat crown is stout and may reach 7m high. The grey Bark may be light or dark and is usually smooth. With time, it may become rough and appear mottled. Young branches are stout and thick.
The opposite or spirally arranged, leathery Leaves are up to 13cm long and are imparipinnate (pinnately compound leaf ending in a single leaflet). These Leaflets occur along either side of the leaf rachis (central stalk), like a feather. There are up to 3 pairs of opposite lateral leaflets and the single terminal leaflet, which is also the largest. The Rachis (main axis bearing flowers or leaflets) and Petiole (leaf stalk) may be noticeably winged. The petiole is up to 2cm long. The elliptic to narrowly obovate Leaflets are up to 5 x 3cm and lack Petiolules (leaflet stalks). The leaflet Apex is narrowly tapered to rounded and may be notched. The Base of each leaflet tapers narrowly. The Margin is entire (with a continuous margin, not in any way indented) and rolled under. It extends down to the rachis (main axis bearing flowers or leaflets). Young leaves may be tinged with pink.
The small, white or slightly pink, sweetly scented, star-shaped Flowers are located in leaf axils. They have compact heads, which are up to 6cm wide. The Tree is dioecious (having male and female parts on separate plants). The unisexual flowers are in panicles (indeterminate, branched inflorescence with stalked flowers). The Calyx is saucer shaped and the Petals are imbricate (having regularly arranged, overlapping edges). An annular Disc (a more or less fleshy or elevated development of the receptacle) is present. The 10 connate (united or joined) Stamens have sessile Anthers. The superior, sessile Ovary has 2 ovules in each locule. The Style is short and thick. The Stigma is obscurely lobed. (Aug-Nov).
The small Fruit is a drupe (a fleshy, 1-seeded indehiscent fruit with the seed enclosed in a stony endocarp; stone fruit e.g. peach). The plant may produce large amounts of fruit. Each drupe is up to 1cm wide and becomes a dull yellow, red or black when mature. (Oct-Feb).
Distribution & Ecology
This Tree occurs below 2 000m in the Western Cape (south eastern part), Eastern Cape, KwaZulu-Natal – mostly here, Mpumalanga, and Limpopo. It has also been found in the highveld of Swaziland. The tree is slow growing and commonly found close to rocks, in rocky ravines, on open woodland, forest margins, close to the escarpment and on krantzes (krantz – encircling or overhanging/precipitous wall of rock).
The Tree grows easily from Seeds. It is slow growing and a good addition to the garden. Both male and female trees are required for fruit production. It also makes a good container plant.
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.
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.