General Info

Tree has grey-brown bark, is up to up to 25m high and may be a strangler. Simple entire Leaves are very big. Tiny Flowers develop in a syconium. Fruit is a stalkless fig.

Description

Tree

Ficus lutea, Ficus vogelii, Ficus quibeba, Ficus nekbudu, Ficus subcalcarata, Ficus utilis, Ficus vogelii.

RSA Tree No. 61.

Common names: Giant-leaved Fig, Reuseblaarvy.

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. lutea – yellow – may refer to the yellow colour of the leaves in autumn or the colour of the lateral veins. The genus Ficus has 24+ species in southern Africa.

Conservation Status: L C. (Least Concern). Assessment Date: 2009.

Tree

This large Tree may initially be epiphytic (the seeds germinate on another tree). If so, the roots may grow down into the ground and the plant grows around the host tree – eventually killing it – hence the term strangler fig. Growing from the ground it can reach 25m in height. The tree has a wide, spreading crown of up to 45m – especially when not surrounded by other trees. In the older tree, the large buttress can be seen (photo 831). Young stems may be hairy. The Bark is dark grey-brown and relatively smooth. After the leaves have fallen, the shiny brown bud-sheaths becomes visible. Non-toxic Latex is released from all damaged or cut parts.

Leaves

The simple, shiny green, alternate Leaves are very large – up to 43 x 20cm on this partially deciduous tree. They tend to be concentrated at the ends of branches. Young leaves tend to be hairy. Leaves are obovate or ovate to elliptic. The Margin is entire (with a continuous margin, not in any way indented but may be hairy) and the Apex is rounded but may end with an abrupt point. The Base is rounded to lobed. There are 6-8 prominent, yellowish Lateral veins on either side of the midrib. The lowermost pair start at the base. Just before reaching the margin, the lateral veins connect with each other via loops which run close to the margin. New leaves are a bright green. The Petiole (leaf stalk) may be hairy. It is stout and up to 13cm long. Shiny Stipules (basal appendages of the petiole) are present and bronze in colour. They initially cover the stem buds and serve as apical bud sheaths. They are distinctively visible just before the new leaves appear. Stipules that envelope terminal bud are caducous (an organ or part which is easily detached and shed early).

Flowers

The plants are monoecious (having both male and female reproductive organs on the same plant) and unisexual or bisexual. Figs possess an amazingly arranged inflorescence 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 singly or in pairs, at the tips of branches or just below the leaves. They are initially hairy but become smooth with time. The hollow fig ends with a tiny opening called an Ostiole that is covered with scales making exit impossible for wasps and entrance difficult. Only the Female pollinating wasp (specific for each species – in this case Allotriozoon heterandromorphum) attempts to do so. She usually injures herself in the process. Around the inner boundary of the hollow receptacle of the fig, a large collection of extremely small flowers is located. The tiny individual flowers are either male or female.

In the Male flowers, up to 6 overlapping perianth (a collective term for the calyx and corolla) lobes and one or 2 anthers are present. The ovary is absent or vestigial (imperfectly developed, non-functional relic from the past). In the Female flowers, there are no stamens and usually fewer perianth lobes. The free Ovary has 1 or 2 styles and the Stigma is usually oblong. The Female wasp enters the fig with her pollen sacks laden with pollen and pollinates those female fig flowers with longish styles that prevent the wasp from laying eggs in those flowers. The wasp targets the flowers with short styles. These they can reach and lays a single egg in each one. These female flowers react producing a gall, which nourishes the developing larvae that eventually pupate and becomes adults. The robust Male wasps develop first, fertilize the young Female wasps and then escape by burrowing through the wall of the fig. This allows oxygen in. The female wasps then, unintentionally load with pollen from the male flowers, escape from the fig and make their way to another fig of the same species. This continues the life cycle. This is an excellent example of a Mutualistic relationship (a beneficial relationship between 2 different species in which both benefit) between the fig tree and the wasp.

Fruit

The stalkless Fruit is a fig that is and up to 2+cm wide. It develops from the synconium (the type of inflorescence found in figs). It is formed by an enlarged, fleshy, hollow receptacle with multiple ovaries on the inside surface. The fleshy hollow receptacle develops into a multiple fruit. It is collectively called a fig. Nearly a week after the wasps have left, the Figs with their fertilized seeds, ripen to a yellow / brown colour. This is due to the oxygen induced ethylene production, initiated by the departing male wasps. 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. (Jun-Oct). Many of the animals that consume the figs Disperse the seeds.

Distribution & Ecology

This Tree often grows on rocky slopes. It can withstand salt spray, windy conditions and grows well at the coast. It is also found in evergreen forests, close to water: from sea level to 1 000m+. It is usually restricted to frost-free areas. If injured this tree exudes a watery, non-toxic, milky sap. Found from southern KwaZulu-Natal, Mozambique, Swaziland, Zimbabwe, and northwards into tropical Africa. The Island groups that contain this tree include Madagascar and the Seychelles. It is now becoming naturalised in Mpumalanga. The tree attracts many frugivorous (fruit-eating animals), including insects and, in turn, the insects attract insectivorous Birds. Monkeys, baboons, bats, duiker, and other Mammals eat the figs. Those birds that eat the fruit may deposit the seeds on other tree branches or elsewhere and so start the cycle over again.

Ethnobotany

This is a most impressive Tree that is widely cultivated in the warmer, moister eastern parts of the RSA. Propagation is by truncheons (quicker) or seeds. The plant is fast growing in a frost-free environment. Although not common among coastal trees, where it does occur, the leaf size makes identification easier. The Sap has been used for birdlime. In Mozambique, cloth has been made from the Bark. At the University of Pretoria, extracts from F. lutea have been shown to have anti-diabetic activity.

References

Boon, R. 2010. Pooley’s Trees of eastern South Africa. Flora and Fauna Publications Trust, Durban. p76.

Coates Palgrave, M. 2002. Keith Coates Palgrave Trees of Southern Africa, edn 3. Struik, Cape Town. p144.

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.

Schmidt, S. Lotter, M. & McCleland, W. 2002. Trees and Shrubs of Mpumalanga and the Kruger National Park. p78.

van Wyk, B. & van Wyk, P. 1997 Field guide to Trees of Southern Africa, Struik, Cape Town. p76.

 

http://redlist.sanbi.org/species.php?species=1906-26

http://repository.up.ac.za/dspace/handle/2263/25061?show=full

http://www.zimbabweflora.co.zw/speciesdata/species.php?species_id=120320

http://natureswow2.blogspot.co.za/2013/08/giant-leaved-fig-ficus-lutea.html

http://pza.sanbi.org/ficus-lutea

http://plantzafrica.com/plantefg/ficuslutea.htm

http://posa.sanbi.org/flora/browse.php?src=SP