A young gifboom growing among sandstone rocks.
The Gifboom is a large evergreen fynbos shrub or small tree endemic to the Gifberg of the northern Bokkeveld Escarpment just south of Vanrhynsdorp (northern part of the Western Cape). The fruits are highly toxic and were formerly used by the San for their arrows and also by local farmers to kill hyaenas.
Erect to spreading, large evergreen shrubs 2–4 m tall and up to 8 m in diameter, often multi-stemmed, due to occasional fires. The sexes are on separate plants. The bark is grey and fissured vertically. Leaves leathery, ascending, simple, in whorls of four, 85–145 x 18–37 mm, shaped like a lance to elliptical, slightly hairy at first, the older leaves becoming hairless and shiny with age. The upper surface is dark green, lower surface light green, nerves slightly visible, except for the quite conspicuous yellowish green midrib. The margin of the leaves is entire, straight to slightly undulating, the base is wedge-shaped (cuneate) and the end is usually blunt (obtuse). The leaves of female plants tend to be smaller than in male plants and the ends taper to an acute point, often ending in a small sharp hard point (mucronate). Male as well as female plants have small, inconspicuous red flowers without petals. The male flowers are borne in conspicuous dense clusters up to 30 mm long. They have five or six irregularly overlapping (imbricate) sepals. The bottom of the male flower (receptacle) is broad, bearing numerous stamens with large, erect anthers producing copious pollen. Female flowers are usually solitary, with 6 sepals in 2 whorls. The ovary is hairy, bearing 3 to 5 large fused styles up to 7 mm long and free for 4 mm. Fruit a 3–4-lobed rounded capsule about 2,5 mm in diameter. Seeds are large, black and shiny (up to 6 per capsule).
Close-up of the male flowers of
Hyaenanche globosa, just before opening.
Close up of the female flowers of
Although not taken up in the Red List of South African plants (Raimondo et al. 2009), it is a rare shrub confined to a small section of the northern Bokkeveld.
A plant growing wild on the Gifberg. Note the rocky habitat.
Distribution and habitat
The gifboom is confined to the northern Bokkeveld Escarpment Mountain Plateau. This includes mainly the Gifberg and Matsikammaberg. These mountains consist of Bokkeveld Sandstone Fynbos (Mucina et al. 2005). The habitat is very rocky and with shallow soil, poor in mineral content. It is derived mainly from quartzitic sandstone of the Cape Supergroup (Table Mountain Group). The plants grow in open, dry fynbos vegetation, sharing its habitat with other fynbos tree and shrub species such as Euclea linearis, Leucospermum calligerum, Paranomus bracteolaris, Maytenus oleoides, Olea europaea subsp. africana, Protea glabra, Protea nitida, Heeria argentea, Osyris compressa, Diospyros glabra and Phylica oleifolia. Smaller succulent plants include Adromischus hemisphaericus, Braunsia maximiliani, Euphorbia loricata, Crassula dejecta, C. atropurpurea var. watermeyeri, C. brevifolia, C. ericoides, C. tomentosa var. tomentosa, Oscularia alba, Tylecodon ventricosus and Cotyledon orbiculata. Summers are hot with cooler winters (frost is light, during winter). Rainfall occurs mainly during winter (cyclonic cold fronts), ranging from 300 – 500 mm per annum.
Derivation of name and historical aspects
The local common name gifboom (gif = poison, and boom = tree) pertains to its toxic attributes and the name Gifberg (gif = poison, berg = mountain) is derived from the common name of this plant.
The gifboom (Hyaenanche globosa) was first documented by a number of prominent European botanists visiting the Cape during the seventeenth and eighteenth centuries. The first to come across this plant was the Van der Stel expedition, en route to the Koperberg, Namaqualand in 1685 (Smith 1966). Carl Thunberg and Francis Masson collected specimens of the plants on their journey to the north in 1774. Shortly after, in 1779, William Paterson, Colonel Gordon and Sebastian van Rheenen also documented the plants on the Gifberg.
The plant was first named by the German botanist Joseph Gaertner (1732–1791) in the eighteenth century as Jatropha globosa. Unaware of Gaertner's name, Thunberg created the name Toxicodendron (literally meaning poison tree), however, this appropriate name could unfortunately not be upheld, as it had been already created by Miller in 1754 for another group of trees in the Anacardiaceae.
Aylmer Lambert (1761–1842) a British botanist, researched the plant and realized it should get a new generic name. He created the genus name Hyaenanche (after its use by farmers to kill hyenas) in 1799 which is still in use today. According to C.A. Smith in Common names of South African plants (1966) Beutler was the first person in 1752 to record the name “wolwegif” (wolf = wolf, gif = poison). This common name was also recorded by Thunberg.
The gifboom flowers mainly during late spring (October to November). The male flowers are very attracti ve and conspicuously red. As the anthers open, pollen is spontaneously released, and dispersed by wind. The male flowers produce pollen in profusion, and at the touch of a flowering branch, a dust cloud of pollen can be clearly observed, so typical of wind pollinated plants. Female flowers are inconspicuous and give rise to rounded fruits, which are green at first, brownish yellow when mature.
|| Hyaenanche globosa mature fruit,
One can ask the question, why the conspicuous red colour of the male flowers, when the plant is clearly pollinated by wind? The reddish colour is commonly observed in young leaves or fruits which mature, and in leaves under stress. This is commonly observed in many succulent plant species. This reddish colour is a result of the producti on of anthocyanins. In young leaves the red pigment protects the soft tissue from excessive radiation from the sun. However in fruit, such as a red peach, the function is to attract the right dispersal agents. The function in the male flowers of Hyaenanche is probably also to protect the young male flowers from excessive radiation.
Uses and cultural aspects
The fruits are highly toxic and were formerly used by farmers to poison hyenas. Lambert (1797) who created the genus name Hyaenanche, had the following comment on its cultural uses, and I quote him:
“This shrub grows about two hundred miles from the Cape, in a rocky soil, in a single spot, on Wind-Hook Mountain near the Elephants River. A farmer lives there who collects the fruit, by which he makes profit of about 20 pounds per annum, selling it for the purpose of poisoning hyenas. The fruit is pounded into a powder and administered in the same manner as Nux Vomica. The powder is put into the carcasses of lambs, which are laid where the hyenas are known to come. By eating its flesh they are infallibly destroyed. The plant flowers and bears fruit annually in the stove of the right honourable, the Earl of Tankerville, at Walton, the only place it has yet flowered in this country, and I believe in no other collections in England. Our figure of the female was drawn from the plant in his lordships stove in 1795; the male from a specimen very obligingly communicated to me by Mr. F. Masson”
According to Watt & Breyer-Brandwijk (1962) the seed of Hyaenanche was used both by bushmen for their arrows, and well as farmers to poison carcasses with the purpose of destroying hyenas. Henkel first isolated the toxic principle from the seed and seed coat. This was named hyaenanchin (C15H18O7) and he found it to be neither an alcaloid nor a glucoside.
The farmer Dave Schlebush from the farm Sewefontein on the Matsikamma Mountain has observed that sheep do nibble on the leaves at times without any ill effect. Dr E.P. Phillips stated that the rocky pools filled by rain water and covered in fallen leaves; do have a negative effect on cattle.
||Young seedlings of the gifboom on the Gifberg
Growing Hyaenanche globosa
Hyaenanche globosa is best grown in dry fynbos gardens (Van Jaarsveld 2010). They require full sun and sandy, mineral-poor soil for best results. This small tree is ideal for summer dry gardens and rockeries. The gifboom is easily propagated from seed.
Seed was collected by the author during 1977 and four years after sowing in the Matthews Rockery at Kirstenbosch National Botanical Garden the resulting plants were planted out. Two of these plants (male and female) have now (2011) reached a height of about 3,5–4 m. The plants first came into flower in 2009, and again in 2010 and 2011. Good seed set was obtained in 2011. The seed takes about a year to mature.
Autumn is the best time for sowing, as it is the beginning of the rainy season. Sow in a standard seed tray. Use a standard well drained, slightly acidic soil mix (2 parts sand, 1 part loam, 1 part compost). Place the seed on the medium and cover lightly with sand. It is best to keep the seed tray partially shaded. Germination commences within about three weeks of sowing. Plants should be first planted in small containers, to be transferred to larger trays. Add organic fertilizer and water well during its growing period.
Plants are relatively disease-free, however they succumb rapidly to Phytophthora.
References and further reading
- Gaertner, J. 1790. De fructibus et seminibus plantarum. 2: 122, t. 109, fig. 3.
- Gunn, M. & Codd, L.E. 1981. Botanical exploration of southern Africa. Balkema, Cape Town.
- Helm, N. 2004. The vegetation of Matsikamma Mountain with some comments on endemicity. Plant Life 30: 5–16.
- Hutchinson, J. 1920. Toxicodendrum in Flora Capensis 4, 2: 408,409. L. Reeve & Co., Ltd., London.
- Lambert, B. 1797. Descriptions Cinch 52, t. 10.
- Leistner, O.A. (ed.). 2000. Seed plants of southern Africa : families and genera. Strelitzia 10. National Botanical Institute, Pretoria.
- Mucina, L. & Rutherford, M.C. (eds) 2006. The vegetation of South Africa, Lesotho and Swaziland. Strelitzia 19. South African National Biodiversity Institute. Pretoria.
- Raimondo, D., Von Staden, L., Foden, W., Victor, J.E., Helm, N.A., Turner, R.C., Kamundi, D.A., Manyama, P.A. (eds) 2009. Red List of South African plants. Strelitzia 25. South African National Biodiversity Institute, Pretoria.
- Smith, C.A. 1966. Common names of South African plants. Memoirs of the Botanical Survey of South Africa No. 35. Department of Agricultural Technical Services. Botanical Research Institute.
- Van Jaarsveld, E.J. 1982. Plantegroei van die Gifberg met spesifieke verwysing na bome, struike en die gifboom. Trees in South Africa. Journal of the Tree Society of South Africa 34: 1 & 2, 10–27.
- Van Jaarsveld, E.J. 2010. Waterwise gardening in South Africa and Namibia. Struik, Cape Town. 2010.
- Watt, J.M. & Breyer-Brandwijk, M.G. 1962. The medicinal and poisonous plants of southern and Eastern Africa. E. & S. Livingstone Ltd., Edinburgh and London.
Ernst van Jaarsveld
Kirstenbosch National Botanical Garden