White stinkwood | |
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Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Clade: | Angiosperms |
Clade: | Eudicots |
Clade: | Rosids |
Order: | Rosales |
Family: | Cannabaceae |
Genus: | Celtis |
Species: | C. africana |
Binomial name | |
Celtis africana | |
Synonyms [3] | |
List
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Celtis africana, the white stinkwood, is a deciduous tree in the family Cannabaceae. Its habit ranges from a tall tree in forest to a medium-sized tree in bushveld and open country, and a shrub on rocky soil. It occurs in Yemen and Somaliland and over large parts of Africa south of the Sahara. [4] It is a common tree in the south and east of southern Africa, where the odour given off by freshly-cut green timber is similar to that of Ocotea bullata or black stinkwood. [5]
Growing as an individual tree in the open and under favourable conditions, Celtis africana becomes a tree of medium height, typically up to 12 m or so. It then usually forms a dense, hemispherical canopy. The bole of a mature tree then is thick and buttressed, often forked fairly near the ground. In forest it may grow up to 25 m tall, with a single, clean bole, though such large specimens usually are more or less buttressed too. In an exposed, rocky position it may be a bonsai-like small shrub. The trunk has a smooth, pale grey to white bark that may be loosely peeling in old trees and commonly has horizontal ridges. [5]
The tree is deciduous in the drier, frostier interior of its range in Africa, but semi-deciduous nearer the coast; in areas with wetter, milder winters it commonly retains its old leaves till after the spring leaf-flush appears. In spring it produces light green, tender, new leaves that contrast with the pale bark. The leaves are simple, alternate, ovate to acuminate in shape with three distinct veins from the base. The leaf margin is slightly toothed (specifically serrate) towards the apex, whereas the basal third tends to be entire. The new leaves are bright, fresh green and hairy on the upper surface; they turn darker green and become smoother as they mature. (Leaf size: 15 to 100 mm length x 10 to 50 mm breadth). [6]
The trees' small flowers are pale yellow in colour, and appear from August to October. Their fruit are carried on long, thin stalks. They are yellow or brown in colour and about 4 mm in diameter. [7]
Occurs in a wide variety of habitats from wet forest and coastal bush to bushveld, mountain gorges and open country, typically savanna. Its range extends from the Western Cape, eastwards and northwards around the southern African coastline, extending inland in the warmer, wetter regions, [8] and further north into Ethiopia. [9]
Celtis africana leaves are browsed by cattle and goats, and also eaten from the ground when shed.
Various species of Celtis are food plants for the larvae of various species of long-nosed butterfly; the genus Libythea . In particular, Celtis africana is the host to Libythea labdaca . The leaves also provide food for the larvae of Caloptilia celtina .
The inconspicuous, small, greenish, star-like flowers appear in early spring (August to October). Male and female flowers are separate, but they are produced on the same tree. Various insects pollinate them, particularly honeybees.
From October to February, following flowering, the rounded, berry-like fruit (botanically speaking drupes) appear. They are borne in large numbers on stalks about 1–2 cm long. As they ripen they change from green to yellow-brown or black. Though small, they typically are plentiful enough to be an important item of diet for many species of frugivorous birds that feed on the fruits and disperse the seeds in their manure. As a result, the seedlings not only may sprout far from the parent trees, but germinate unpredictably in all sorts of cracks in rocks or rotting wood as well as in fortunate locations in good soil. Their attraction for birds renders Celtis africana a popular tree in planning bird-friendly gardens.
Fruit and seeds are eaten by various animals, including chacma baboon, vervet monkey, tambourine dove, Cape parrot, Rameron pigeon, Knysna lourie, purple-crested lourie, mousebirds, black-collared barbet, crested barbet, Karoo thrush, Cape robin-chat, chorister robin-chat, Cape bulbul, black-eyed bulbul, plum-coloured starling and thick-billed weaver. [10]
The species is easily propagated from seed, though for best results it is well to collect ripe fruit from the tree itself because seeds in dropped fruit commonly have been damaged by insects. It is best to separate the seed from the fruit tissue before planting, because the pulp inhibits germination until it has been removed by the digestive processes of birds. Celtis africana is a useful tree for planting along roadsides in urban areas of southern Africa. [5]
Seedlings are best planted out in good soil several metres away from paving and walls, but once established, they will do well even in fairly challenging conditions.
There is some reluctance to plant the tree in small gardens because it grows quite large, and some care is necessary because heavy branches growing at an unfavourable angle may split off and fall dangerously. This can however be forestalled and prevented by competent pruning and other arboricultural practices.
Related nettle trees of the genus Celtis have been introduced to South Africa, and are readily confused with the white stinkwood. These species, which typically have the leaves less hairy, have been introduced as shade trees in gardens and parks, or invade river banks and other city spaces. [7] Some of them also hybridize, as all are wind pollinated. C. occidentalis , of American origin, is distinguishable by the warts on it bark, besides the distinctly larger purple or black fruit of some 1 cm in diameter. [7] C. australis is of Mediterranean origin. Its leaves have a rough upper side, and the fruit resemble those of C. occidentalis. C. sinensis is of oriental origin and has dark, glossy leaves, that are only hairy on the underside. Its fruit are dark orange and about 6 mm in diameter. Its numerous fruit are carried on short and sturdy stalks. [7]
The pigeonwood ( Trema orientalis ) was formerly classified as a Celtis species, and is likewise easily confused with the white stinkwood. The white stinkwood has nothing in common with the black stinkwood, a source of high-quality timber, which acquired its name from the strong smell of freshly felled trees.
Celtis is a genus of about 60–70 species of deciduous trees, commonly known as hackberries or nettle trees, widespread in warm temperate regions of the Northern Hemisphere. The genus is part of the extended Cannabis family (Cannabaceae).
Stinkwood, german Stinkholz, french Bois Puant, is the common name for a number of trees or shrubs which have wood or plant parts with an unpleasant odour, including:
Ocotea bullata, is a species of flowering tree native to South Africa. It produces very fine and valuable timber which was formerly much sought after to make furniture. Due to over-exploitation it is now a protected species. Other names for it are Cape Walnut, Cape laurel, and laurel wood. The name "stinkwood" comes from a strong smell that is released when it is fresh felled.
Celtis occidentalis, commonly known as the common hackberry, is a large deciduous tree native to North America. It is also known as the nettletree, sugarberry, beaverwood, northern hackberry, and American hackberry. It is a moderately long-lived hardwood with a light-colored wood, yellowish gray to light brown with yellow streaks.
Protea neriifolia, also known as the narrow-leaf sugarbush, oleander-leaved sugarbush, blue sugarbush, or the oleanderleaf protea, is a flowering plant in the genus Protea, which is endemic to South Africa.
Protea gaguedi is a species of tree which belongs to the genus Protea.
Protea welwitschii is a species of shrub or small tree which belongs to the genus Protea, and which occurs in bushveld and different types of grassland.
Newlands Forest is a conservancy area on the eastern slopes of Table Mountain, beside the suburb of Newlands, Cape Town, South Africa. It is owned and maintained by the Table Mountain National Parks Board, along with the City Parks Department of Cape Town, and includes a Fire Station, Nursery and Reservoir.
Celtis reticulata, with common names including netleaf hackberry, western hackberry, Douglas hackberry, netleaf sugar hackberry, palo blanco, and acibuche, is a small- to medium-sized deciduous tree native to western North America.
Celtis mildbraedii is a species of forest tree in the family Cannabaceae. It was previously assigned to the family Ulmaceae. These trees grow in limited areas of South Africa, Mozambique and Zimbabwe. They are also found in forested areas from West Africa to Sudan, DRC, Angola and Tanzania. Common names include natal white stinkwood, red-fruited white-stinkwood and natal elm. This species is more common in Tropical Africa than in Southern Africa.
Areas of forest which grow in KwaZulu-Natal, South Africa mostly on south facing slopes in higher rainfall areas, and along the humid coastal areas. Different types of forest can be identified by their species composition which depends mostly on the altitude, latitude and substrate in which they grow. South facing slopes are favourable for the development of forest as they are more shaded, and therefore cooler and retain more moisture than the northern slopes. The extra moisture on the south slopes is not only favoured by forest trees, but also helps to prevent or subdue wildfires. Fires can also be blocked by cliff faces and rocks or boulders on these slopes, and by streams or rivers at the base of the slopes. The coastal regions are conducive to forest formation, because of high rainfall and humidity which are favoured by forest trees and also help to prevent or subdue fires. The rivers of the coastal areas are also broader than further inland, which may often prevent fires from spreading long distances, and fires generally burn uphill and therefore more often away from areas at low altitude.
Kiggelaria africana is a large, robust, low-branching African tree, and is currently the only accepted species in the genus Kiggelaria.
Grewia occidentalis, the crossberry, is a species of deciduous tree, indigenous to Southern Africa.
Southern Afrotemperate Forest is a kind of tall, shady, multilayered indigenous South African forest. This is the main forest-type in the south-western part of South Africa, naturally extending from the Cape Peninsula in the west, as far as Port Elizabeth in the east. In this range, it usually occurs in small forest pockets, surrounded by fynbos vegetation.
Combretum kraussii, the forest bushwillow, is a medium-sized to large tree of eastern South Africa, Eswatini and southern Mozambique, which is found within, or in the vicinity of forests. The specific name commemorates Dr. F. Krauss who undertook a collecting trip to South Africa from 1838 to 1840.
Commiphora africana, commonly called African myrrh, is a small deciduous tree belonging to the Burseraceae, a family akin to the Anacardiaceae, occurring widely over sub-Saharan Africa in Angola, Botswana, Burkina Faso, Chad, Eswatini, Eritrea, Ethiopia, Kenya, Mali, Mauritania, Mozambique, Namibia, Niger, Senegal, Somalia, South Africa, Sudan, Tanzania, Uganda, Zambia and Zimbabwe. On sandy soils this species sometimes forms pure stands, deserving consideration as a plant community or association.
Erythrina zeyheri, commonly known as the ploughbreaker, is a deciduous, geoxylic subshrub and member of the Fabaceae, which is endemic to southern Africa. It grows no more than 60 cm tall and occurs naturally in the higher elevation grasslands of South Africa's central plateau, and that of adjacent Lesotho. They favour deep clay soil in the vicinity of creeks and marshes, and often form colonies. Its specific name commemorates the 19th century botanist, Karl Zeyher.
Euclea crispa, commonly known as the blue guarri, is an Afrotropical plant species of the family Ebenaceae. The hardy and evergreen plants may form a dense stand of shrubs, or grow to tree size. It is widespread and common in the interior regions of southern Africa, and occurs northward to the tropics. Though some are present near the South African south and east coasts, they generally occur at middle to high altitudes. It is readily recognizable from its much-branched structure and dull bluish foliage colour. Those bearing lanceolate leaves may however resemble the Wild olive, another common species of the interior plateaus.
Dalbergia armata is a scrambling, deciduous species of legume that is native to subtropical to temperate regions of southeastern Africa. The robust, woody liana or small tree is armed with strong spines on the main stem and branches. It occurs sparsely or commonly in forest, bush, riparian fringes and in wooded ravines. It is sometimes employed as a bonsai subject, and it can be propagated from either seed or cuttings.
The Victoria Basin forest–grassland mosaic is an ecoregion that lies mostly in Uganda and extends into neighboring countries. The ecoregion is centered north and west of Lake Victoria, with an outlier on the border of Ethiopia and South Sudan.