Tree may reach 25m high. Large, simple Leaves have a distinct pair of lateral veins at the base. The inflorescence is a syconium with tiny monoecious Flowers. The Fruit is a fig.
Ficus trichopoda, Ficus hippopotami, Ficus congoensis, Ficus zuvalensis.
RSA Tree No. 54.
Common names: Swamp Fig, Moerasvy, umVubu: the hippo fig in isiZulu, isiXhosa, seSotho. They have the same distribution as the hippo.
Family: Moraceae (fig or mulberry family). Trees are evergreen and have milky or watery latex present. Leaves are usually entire and stipules are present. Simple leaves are alternate or opposite and 3-veined from near the base. Plants are monoecious or dioecious and flowers are unisexual. The Perianth of indigenous species contain sepals but no petals. Male flowers have up to 6 stamens. Female flowers are inconspicuous and lack staminodes. The superior or inferior Ovary has 1 locule with 1 ovule and 2 styles are often present. The compound Fruit contains various Seeds. The family has 37+ genera and 1 100+ species. There are 4 genera and 29 species in southern Africa.
Name derivation: Ficus – Latin for fig. trichopoda – hairy feet – may refer to the thin, down hanging branchlets. The genus Ficus has 24+ species in southern Africa.
Conservation Status: L C. (Least Concern). Assessment Date: 2009 (Raimondo et al.).
This Tree, with a rounded spreading crown, may reach 12m and occasionally 25m in height. The Stem is often horizontal and, in swampy areas, about 2m above the ground. Descending from this are impressive prop roots. This is a unique diagnostic feature for this southern Africa fig tree and is known as a Banyan growth form. These aerial roots develop into new stems and this can extend the reach of the tree (photo 197). Initially the Trunk is smooth, pale grey-green to brown. The Bark becomes rough with age. Apical bud sheathes are a light red colour. All damaged parts of the plant exude non-toxic milk latex.
The alternate, leathery, oblong to ovate Leaves are velvety below and large – up to 30 x 23cm. The Blade is a dark shiny green above and blue-green below. There are 6-11 pairs of clearly visible pale whitish Veins, which may be slightly pink. A distinct pair of lateral veins is at the base and together with the broad midrib, makes the leaf 3-veined from the base. On the lower surfaces, Waxy spots occur in axils of secondary veins or at base of the leaf midrib. Leaves are not rough and sandpaper-like and, apart from the midrib, lack hairs. Young leaves are red. The Apex is broadly tapering and bluntly pointed. The Base is rounded to square and might be lobed. The Petiole (stalk of leaf) is thick and up to 4cm long. The shiny Stipules (basal appendages of the petiole) are large – up to 4,5cm long. They envelope terminal bud and are caducous (an organ or part which is easily detached and shed early). When leaves fall, they leave a leaf scar.
Flowers. The tree is monoecious (having both male and female reproductive organs on the same plant). The Inflorescences contain both sexes but individual flowers are either male or female. Figs possess an amazingly arranged flower head called a Syconium. Essentially this consists of a Receptacle (is that expanded tip of the flower stalk from which the floral parts develop) whose perimeter substantially increases in size and folds over forming the fig shape. Figs occur in axils of young leaves and on young twigs. The hollow fig ends with a tiny opening called an Ostiole, which is covered with scales making exit for wasps impossible and entrance difficult. Only the female pollinating wasp (specific for each fig species – in this case Elisabethiella bergi breviceps in the RSA) attempts to do so. She usually injures herself in the process.
Around the inner boundary of the hollow receptacle of the fig, large collections of extremely small flowers are located. The Male flowers have up to 6 overlapping perianth lobes and one or two anthers are present. Here the ovary is absent or vestigial. In the Female flowers, there are no stamens and usually fewer perianth lobes. The Ovary is free and usually has 2 Styles. The Female wasp enters the fig laden with microscopic pollen. It then “accidently” pollinates those female fig flowers with longish styles. These long styles prevent the wasp from laying eggs in that specific ovary. The wasp targets the flowers with short stigmas and lays a single egg of their ovaries. This female fig flowers react, producing a gall, which nourishes the developing wasp larvae. These larvae eventually pupate and becomes adults. The robust Male wasps develop first, fertilize the young female wasps and then burrow through the wall of the fig allowing oxygen in. The Female wasps then, unintentionally, loads pollen from the male flowers. They then escape from the fig and make her way to another fig, of the same species, to continue the life cycle. They escape through the opening created by the young male wasps. This is an excellent example of a Mutualistic relationship (a beneficial relationship between 2 different species in which both benefit) here between the fig tree and the wasp.
Nearly a week after the wasps have left the figs, with their fertilized seeds, the figs Ripen. They then develop into a multiple Fruit. Up to 4 may occur in each leaf axil. The fruit stalk is up to 1,2cm long and the mature figs are up to 2,5cm wide. The fruit changes from hairy green and becomes orange or red and mottled with pink when ripe. This is due to the oxygen induced ethylene production. Ethylene is a small hydrocarbon gas – odourless and tasteless. This gas is involved in the ripening of the fruit, including causing the fruit to change colour, texture and soften. It is used commercially to ripen fruits like tomatoes, bananas and pears. (Sep-Apr).
Distribution & Ecology
This is a protected tree in the RSA. It is common in frost-free swamps and forests and may occur together in clumps of trees. Trees are located in KwaZulu-Natal North Coast, Mozambique to East and central Africa. They are also located in Madagascar. Swamp Figs are eaten by birds e.g. the Natal thrush, and by monkeys. There is a good specimen, with a prehistoric appearance, in the Durban Botanical Gardens. This is the oldest botanical garden in Africa and all their trees are very impressive. It was initially established in 1849 before being relocated to its present site.
This tree makes good pot-plants and bonsai. This is a good tree to have indoors. The Foliage is very attractive – more so than other fig leaves. Plaited rope has been made from the Bark which has strong fibres. Latex makes good birdlime.
Boon, R. 2010. Pooley’s Trees of eastern South Africa. Flora and Fauna Publications Trust, Durban. p80.
Coates Palgrave, M. 2002. Keith Coates Palgrave Trees of Southern Africa, edn 3. Struik, Cape Town. p151.
Lawrence, G. H. M, 1951. Taxonomy of Vascular Plants, The Macmillan Company, New York. Tenth Printing 1965.
Palmer, E. & Pitman, N. 1972. Trees of southern Africa, Balkema, Amsterdam, Cape Town. p465.
van Wyk, B. & van Wyk, P. 1997 Field guide to Trees of Southern Africa, Struik, Cape Town. p82.