Growing occidentalis Description Grewia occidentalis makes a decorative garden , Virgilia divaricata and V. oroboides are very similar which is both frost and drought hardy. It will grow well and are often confused with each other. Both are if well watered and planted in good, composted soil. small to medium-sized trees, with a bushy, rounded The cross-berry may be planted in either full sun or to broadly conical growth habit with branches growing shade. The root system is not aggressive and the close to the ground. They are very fast growing when shrub can therefore be planted near buildings and young, attaining up to 1.3 m in a year, and reaching paving. It is a “must-have” species in the garden to their full height in only a few years. V. divaricata rarely attract butterflies and birds. exceeds 10 m in height; V. oroboides can reach up to 15 m. They are also relatively short-lived, their aver- age lifespan being 12 to 20 years. The bark is silver- 3. Virgilia oroboides grey and smooth in young trees; as the tree gets older the bark turns grey and rough. The trunk can grow up Family: Fabaceae (pea and bean family) to 600 mm in diameter. Common names: blossom tree (Eng.); keurboom The keurboom has beautiful, sweetly scented, pea- (Afr.) Distribution shaped flowers in dense terminal sprays about 100 mm long. V. divaricata has pinkish mauve to violet- The keurboom is native to a small, narrow strip pink flowers and the keel has dark-purple tips. The along the southeastern coast of . Virgilia flowers are produced in profusion in spring to early oroboides is found below 1 200 m in a narrow strip summer. V. oroboides flowers are pale pink or pinkish along the coast from the Cape Peninsula to George. white to white and they are produced in profusion in V. divaricata also occurs below 1 200 m but from Klein mid to late summer. Swartberg Mountains to George to Van Staden’s Pass Just to add to the confusion, the V. oroboides trees near Port Elizabeth in the Eastern Cape. Both occur in near George have rose-violet or purple-violet flowers forest margins, most often beside streams or on river- during spring, but can be differentiated from V. divari- banks but also on hillsides and thickets. V. divaricata cata by the conspicuous rust-coloured hairs that cover is found in abundance in the Knysna and Plettenberg the leaves and twigs. Both species flower sporadically Bay area, particularly along the Keurbooms River, out of season. Both produce a flat, brown, velvety 50 which takes its name from this tree. to80 mm long pod, becoming black with age, which Derivation of the name and histori- splits into 2 valves releasing 2 to 6 seeds. cal aspects These two species have a rather complicated history Gardeners need not hesitate on the choice of tree if of naming. Virgilia oroboides has quite a few syno- the keurboom is on the list; it is a beautiful tree, suita- nyms and both have been called V. capensis although ble for both the domestic garden and big landscapes. by different authors. There is still an argument about It is fast growing, beautiful in flower and has an attrac- whether they are one variable species or two separate tive growth form. species.

At present they are regarded as two separate spe- cies, and V. oroboides is divided into two subspecies; the rose-violet-flowered plant with rust-coloured hairs on the leaves and twigs that occurs near George be- ing V. oroboides subsp. ferruginea and the pale, pink- National Arbor Week flowered plant with white hairs on the leaves and twigs that occurs from the Cape Peninsula to Swellendam 1–7 September being V. oroboides subsp. oroboides. Growing V. oroboides and V. divari- 2013 trees cata A keurboom is the perfect tree for the new, bare garden because it grows so fast it will take only two or three years before it will be creating shade, or a screen, and filtering the wind—which is an important consideration in suburbs. It is also one of the best species to use as a pioneer in the first stage in the succession to forest. It is content to grow out in the open, grows fast and quickly and creates the shade that the slower-growing, more permanent trees need to grow in. Virgilia is propagated from seed. The seed coat is hard and requires some stimulation to initiate ger- South Africa hosts mination. Seeds can be soaked in hot water before sowing, or the seed coat can be cracked artificially. the XIV World Forestry Seed can also be sown in situ, e.g. for forest reha- bilitation projects. The seeds are highly fertile and can Congress in 2015 remain alive and dormant for many years after they have fallen, even after as many as 30 years they will germinate if conditions are favourable. To find out if SANBI has seed of this or other SA species, please email our seedroom. This page forms part of the South African National Our forests-our future Biodiversity Institute's plant information website http://www.plantzafrica.com/ agriculture, 2013 Design by Directorate Communication Services forestry & fisheries Department: Agriculture, Forestry and Fisheries REPUBLIC OF SOUTH AFRICA 1. racemosa Description ern China, northern Australia, the Ryukyu Islands of Japan and a number of Polynesian islands. It does Barringtonia racemosa has a straight, unbranched grow well under dry conditions but it cannot tolerate stem that leads to a rounded crown and it is usually 4 Family: even mild frost to8 m tall, but occasionally reaches 15 m. The bark is Common names: Powder-puff tree (Eng.); poeierk- greyish brown to pink with white blotches and raised Ecology wasboom (Afr.); iBhoqo (isiZulu) South African Na- dots and lines. The branches are marked with leaf tional Tree No. 524 Barringtonia racemosa can tolerate salt water and scars. therefore thrives under coastal and estaurine condi- tions. It also grows well under dry conditions where frost does not occur. The chief dispersal agent for the buoyant seeds is the tide. Although there are no re- cords of animals eating the fruit, the presence of the trees up to 1 000 m above sea level points to a pres- ently unknown animal as a dispersal agent. It flowers twice a year: in spring and again from January to April. The strong scent produced by the flowers at night at- tracts moths and nectar-feeding bats. After the flow- ers (petals and stamens) are shed, the inflorescences are often crowded with ants that are attracted to the This beautiful mangrove tree is easily recognised by nectar. It is the food plant for the butterfly Coeliades keithloa larvae. its large leaves, delicate white flowers and guava-like The flowers are produced on hanging racemes up to fruit that hangs in long racemes. 1 m long. The buds are pinkish red and split open to Uses and cultural aspects bring forth masses of delicate stamens in white sprays up to 35 mm wide, which are often tinged with pink. The seeds, bark, wood and roots contain the poison The flowers emit a pungent, putrid yet faintly sweet saponin and is used to stun fish. The bark, which also odour in the morning. The fruit is quadrangular, 65 x has high tannin content, is frequently used in pow- 40 mm. Each fruit contains a single seed surrounded dered form for this purpose. Extracts from the plant by spongy, fibrous flesh that provides the buoyancy are effective insectides and in South Africa the Zulus that allows the fruit to be carried off with the tide. use the fruit to treat malaria. The young leaves are ed- ible and the bark is often used for cordage. Distribution Barringtonia racemosa is mainly a coastal species that thrives under very humid, moist conditions. It is common along tropical and subtropical coasts in the Indian Ocean, starting at the east coast of South Af- rica. It is also widespread in Mozambique, Madagas- car, India, Sri Lanka, Malaysia, Thailand, Laos, south-

sa is deciduous, dropping its leaves for a short time in be found in almost all areas. The natural distribution early summer before the first rains on the east coast of the Grewia occidentalis ranges from the Western of KwaZulu-Natal. Cape up to Zimbabwe and Mozambique. This genus is named after Nehemiah Grew (1641-1712), an Eng- lish physician. Occidentalis means from the west. 2. Grewia occidentalis L. Description It is a scrambling, deciduous shrub or small tree, Family: Buddlejaceae reaching up to 3 m in height. Purple star-shaped flow- Common names: Common names: Cross-berry, ers appear in summer, followed by distinctive four- four-corner (E), kruisbessie (A), Mokukutu (Setsw.), lobed fruit (hence the common name cross-berry and Mogwane (N.Sotho), iLalanyathi (Zulu), umSipane four-corner). The fruit turns shiny reddish brown to (Siswati), umNqabaza (Xhosa), Mulembu (Venda), light purple when ripe and may remain on the tree for Nsihana (Tsonga) long periods. Family: Leaves are browsed by cattle, goats and game (black rhino, giraffe, nyala and grey duiker). Ripe fruit is rel- ished by various birds such as louries, mousebirds, Growing Barringtonia racemosa bulbuls and barbets as well as certain mammals (in- It grows rapidly from the seed or cuttings that are cluding man). Larvae of the rufous-winged elfin but- pushed into the ground. The typical substrate on terfly (Eagris nottoana) and buff-tipped skipper (Ne- which it grows is the black mud on the banks of the trobalane canopus) feed on the leaves of this species. estuaries on South Africa’s east coast. Uses and cultural aspects When growing it in a garden (or relatively dry condi- tions), it is best to water it regularly during the estab- In certain areas where the sugar content of the fruit is lishment phase and during winter, otherwise the plant high, it is collected and dried for later use. The dried is likely to die off. In Durban and Sri Lanka the weath- fruit is sometimes boiled in milk—a bush milkshake! er is such that it is used as a roadside tree. Generally Beer is also brewed from the ripe fruit in certain areas. B. racemosa cannot tolerate even mild frost, however, Other human uses of this species include using the it has been grown successfully on the Highveld when wood to make bows and spear shafts. kept in a greenhouse under permanently well-watered National Tree List No. 633 The cross-berry is an important species in tradition- and very humid conditions. al medicine and is used for a variety of purposes. This attractive, indigenous shrub may be found in a The very large, spear-shaped leaves provide plenty Bruised bark soaked in hot water is used to treat variety of locations, ranging from arid karoo, coastal of shade and any grown in close proximity to wounds. Pounded bark, used regularly as a shampoo, dune bush, evergreen montane forest and wooded the tree should be shade plants that can tolerate very was believed to prevent hair from turning grey. Parts grasslands. On the Highveld, it mainly grows in clumps moist soils. It is well suited for small gardens because of the plant were used to treat impotence and sterility, of bushes and in rocky places, often in the shade of the horizontal branching of B. racemosa makes the and root extracts were used to help in childbirth. trees— it occurs naturally in the Witwatersrand Na- canopy easy to prune to the required size. B. racemo- tional Botanical Garden where it is common and may