This tree is famous in South Africa for being used to make Van Riebeeck's Hedge, the first formal boundary marker between the new Cape colony and the indigenous people of the Cape.

Description
The wild almond is most often a large, spreading multi-stemmed shrub to 5 m or a sturdy, well-shaped evergreen tree to 15 m. It has wide spreading branches and a sprawling habit. The bark is thick, rather smooth, pale greyish-brown in colour and attractively striped and mottled.

The leaves are dark green, hard and leathery to the touch, long and lance-shaped, irregularly and sharply toothed, with a prominent midrib. They are arranged in whorls of six at intervals along the stems, radiating out like a star around the branch. Young growth is soft and golden as it is densely covered with rusty-brown hairs.

The inflorescence is an approx. 8 cm long dense raceme of small (each about 5 mm long), white and sweetly scented flowers. Flowering time is mid summer (December-January). The fruits are carried in clusters at the tips of branches, and look very similar to almonds. They are almond-shaped, up to 45 mm x 30 mm, and densely covered with rusty or chocolate-brown velvety hairs. The young fruits are an attractive magenta or lilac-purple colour and mature to the typical brown in late summer - autumn (February-May).

Distribution
Wild almond trees are confined to the fynbos biome and can most often be found growing near streams on the lower slopes and in sheltered valleys from Gifberg near Clanwilliam to the Hottentots Holland to Klein Rivier Mountans and from the Cape Peninsula to the Riviersonderend Mountains to Riversdale. On the Cape Peninsula, they are abundant on the eastern side of Table Mountain and there are many growing beside the streams that pass through Kirstenbosch. This species is not threatened.

Ecology
Brabejum stellatifolium is pollinated by insects, and it attracts many of them while in flower, as well as insectivorous birds. The fruits float and are dispersed by water. They are also short-lived and die in storage. Furthermore, if they do not germinate and establish themselves fast, before the first winter rains, they may be washed out to sea. The fynbos biome is fire prone, and the wild almond survives the normally quick fynbos fires by resprouting from the stem. The leaves and stems of many plants are disfigured by knobs. These are domatia (little houses) caused by symbiotic mites. They do not do any damage to the plants, but are rather unsightly and affected branches can be cut off if they offend. The fruits are eaten by porcupines and squirrels without any toxic effect. Beekeepers report that the honey from wild almond trees has a bitter aftertaste.

Derivation of the name
Brabejum stellatifolium is the only member of the genus Brabejum, sometimes incorrectly spelled Brabeium. This name is based on the word brabeion, which is Greek for sceptre and may refer to the inflorescence. But, a brabeion was also the prize awarded at the Pythian games held at Delphi, the prize being a crown of bay or laurel leaves, so it could equally refer to the vague resemblance between Brabejum leaves and those of the bay or laurel tree. The specific name stellatifolium means that the leaves radiate like the points of a star, which they do. The vernacular names bitteramandel (bitter almond) and wild almond are derived from the resemblance of the fruit to the almond. The bitter taste is due to the presence of cyanogenic glycosides that liberate prussic acid (the toxic principle) when eaten. The ghoe- in the names ghoeboontjie and ghoekoffie is the original Khoi name for the kernels of the fruits. Boontjie is the Afrikaans for bean and koffie (coffee), refers to the use made of the fruits.

Despite the resemblance of the fruits to the almond, the bitter almond is not an almond at all but a member of the protea family. Although by no means the most spectacular member in a pretty spectacular family, it is nevertheless of great interest to the botanist and the phytogeographer. What makes it fascinating to them is that Brabejum has no close allies among its African protea relatives, but is most closely related to Macadamia, a proteaceous genus that occurs an ocean away in Australia and New Caledonia. The protea family is divided into two subfamilies, the Proteoideae and the Grevilleoideae which are distinguished on one simple character: in Proteoideae a single flower is borne in the axil of a bract, while in Grevilleoideae two flowers are borne in the axil of a bract. Brabejum is the only African member of the family that has two flowers in the axil of a bract. All the other members of its subfamily are found mainly in Australia, but also in Malaysia, South East Asia and South America. The protea family is also an ancient family, a descendent of Glossopteris that lived more than 200 million years ago, and with fossils that date back to Permian times. It seems to prove the theory of continental drift, and points back to an ancient time when South America, Africa, India, Antarctica and Australia were all one continent, Gondwanaland, that split up and drifted apart about 130 million years ago. The family must have evolved and flourished on that super continent, and millions of years later its descendants still occur on the pieces that are now separated by thousands of miles of ocean. Brabejum is the lone survivor of its branch of the family tree on the African piece of Gondwanaland.

History
The bitteramandel played a starring role in the early colonial history of South Africa and has a number of unique distinctions. The name bitteramandel was the first to be applied to an indigenous poisonous plant when van Riebeeck mentioned it by that name in April 1654 in connection with it being a potential pig food. He was fully aware that the fruits were poisonous, and that the indigenous Khoi people ate them after treating them to get rid of the poison. His plan was to experiment with various pre-treatments to see if they would make a suitable pig food.

The wild almond is the culprit in the first recorded case in South Africa of a human death by poisoning. One of the members of Jan Wintervogel's 1655 expedition died from eating too much bitter amandelen.

It also featured in a dispute over opposing territorial claims between the European colonists and the Khoi. After the 1659-60 war between them, a vital item in the ensuing peace negotiations regarded the claim by the Khoi people to a population of these trees which was now part of the colonial settlement, but had been theirs until then. They claimed ownership or at very least access to collect the fruits and to dig up the roots for winter food. The Dutch did not grant this petition saying that it would give them too much opportunity to damage the colony and the colonists (they regarded them as thieving, marauding and murderous), and in any case they wished to use the seeds themselves, to plant a defensive hedge.

This project had been mooted the year before, it involved the planting of a live hedge to form the eastern boundary of the settlement. Building such boundaries was something that was apparently done quite often in Holland, where the Graven and Heren (counts, earls etc) used canals or ditches or anything that cattle could not cross to demarcate the area of their jurisdiction. The plan was to plant bitteramandel trees along the 13 km bow-shaped eastern boundary from the mouth of the Salt River passed Ruijterwacht in Rondebosch, beside the Black River over Wynberg Hill ending up at Kirstenbosch, and to leave a 3,6 m strip unplowed to encourage the growth of fast-growing brambles and thorny plants so that the hedge would be thick and dense so that no livestock could be driven through it. There were openings, or posts, at various points through which people and livestock could pass.

This was the first comprehensive frontier for the colony until the Grootvisrivier was proclaimed the eastern boundary in 1798. In any event, although it grew fast and well, the boundary hedge never performed the service it was expected to. One of the first things they realised was that the good grazing was on the other side, and the spread of the colony could not be limited by that artificial boundary. Nevertheless, parts of the hedge in Bishopscourt and at Kirstenbosch are still alive and well and older than any existing man made structure from that time, including the Castle. Our portion of the hedge was proclaimed a national monument in 1936 and the Bishopscourt section in 1945.

Brabejum stellatifolium was one of the earliest Cape plants to be introduced to Europe and was published by Breynius c. 1668.

Uses
The original inhabitants of the Cape are known to have used the fruits for food, and to have dug up the roots as food for winter. The fruits are poisonous, particularly when fresh, but the poison can be leached out by soaking them in water for several days, then boiling and roasting them. The early settlers at the Cape took over the practice of soaking, boiling, roasting and grinding the fruits to make a coffee substitute from the Khoi. The timber is red and reticulated and hard to saw. It was used in joiners' and turners' work, and was once popular for ornamental work. It was also used to make bowls, the heels of Dutch shoes, wagon felloes (rim of the wheel) and brake blocks. The bark has been used for tanning.

Growing Brabejum stellatifolium

The bitter almond is relatively fast growing, particularly in well-composted, well-watered soil and is definitely not suitable for the small garden. It has a tendency to spread sideways and is suitable for hedging and screening. If correctly pruned, it can form a well-shaped tree. It is best not to remove the lower shoots or to stake the main stem as it is easily broken by wind if it gets top heavy. Wherever side branches are cut, thick branches will grow from below the cut, so it is readily shaped into a good screen or hedge. Old specimens make wonderful magical places for kids as the sprawling branches form a giant tangle of huge boughs just begging to be climbed on and explored. One of the footpaths on the Kirstenbosch Estate takes you through an old tree and you have to duck under some of the huge branches and climb over others.

Propagate by fresh seed sown in late summer - autumn (Feb-May). The fruits can be sown as is, i.e. no extraction of the seed is required, and they should germinate immediately when they find themselves on a piece of firm, damp soil. There is no need to bury them too deep, they can be placed flat on the surface, or pressed in halfway or until they are just covered. The radicle and shoot will emerge from the pointed end of the fruit. An efficient way is to place 2 or 3 fruits in a 4 kg bag and at least one should germinate. They can also be germinated between two layers of wet hessian (sacking) and then transferred to a bag or pot. Use a light, compost-enriched soil. They are recalcitrant, i.e. they are short lived and will die relatively soon after being stored, even if kept in the fridge. Dried out fruits will not germinate. Seedlings can be potted up into larger bags or planted out when they are about 10 cm tall. Either plant them into an area that is permanently damp, like a stream bank, or make sure that they are well watered particularly during their first 2 years.

Wild almond trees can be budded onto macadamia trees and vice versa.

References

• Smith, C.A. 1966. Common Names of South African Plants. Dept. of Agricultural Technical Services, Botanical Survey Memoir No 35, Government Printer.
• Rourke, Dr. J.P. 1971.Van Riebeeck's Wild Almond - Odd Man Out of the South African Proteaceae. Veld & Flora.1:53-55.
• Jackson, W.P.U. 1990. Origins and Meanings of Names of South African Plant Genera. U.C.T. Printing Dept., Cape Town.
• Coates Palgrave, M. 2002. Trees of Southern Africa, Third edition. Struik Publishers, Cape Town.
• Palmer, E. and Pitman, N. 1972. Trees of Southern Africa. A.A. Balkema, Cape Town.
• Protea Atlas Project. http://protea.worldonline.co.za
• Oberholster, J J. 1972. Historiese Monumente van Suid Afrika. Rembrandt van Rijn Foundation. Cape Town.

Alice Notten & Christien Malan
Kirstenbosch National Botanical Garden
September 2003