General Info

Tree may reach 15m high. Old bark is longitudinally fissured.  Bipinnate Leaves have asymmetric leaflets. Bisexual, zygomorphic Flowers in terminal racemes. Petals are free. Fruit is a flattish pod with 1-2 Seeds.

Description

Peltophorum africanum, Brasilettia africana.

RSA Tree No. 215.

Common names: Weeping Wattle, Weeping-wattle, African wattle, Huilboom, African Blackwood, Black Wattle.

Family: Fabaceae or Leguminosae. (Pea, bean or legume family).  After the Orchidaceae and the Asteraceae, the Fabaceae is the third largest Angiosperm (flowering plants) family with 700+ genera and close to 20 000 species.  Local Tree genera include Acacia (Vauchellia, Senegalia), Albizia, Bauhinia, Bolusanthus, Burkea, Calpurnia, Colophospermum, Cyclopia, Dichrostachys, Erythrina, Erythrophleum, Faidherbia, Indigofera, Mundulea, Peltophorum, Philenoptera and Schotia.  The Fabaceae are recognisable by their fruit and by their pinnately compound Leaves. Leaves may also be simple and usually have stipules – some of which may be spinescent. Leaflets are usually entire.  Flowers are bisexual and bracteate. Regular flowers usually have 4-5 sepals and the same number of petals.  Irregular flowers have 4-5 sepals and 5 or less petals.  Stamens have anthers that have 2 pollen sacs and there are usually at least twice the number of stamens as petals – often 10.  The superior Ovary has one locule that may contain 1 or more ovules.  The Stigma and Style are simple. The single carpel develops into the Fruit, which is usually a pod.  The pod dehisces on both sides and may break into segments. Seeds vary.

Name derivation: Peltophorum – shield shaped – referring to the Stigma. africanum – from Africa.

Conservation Status: L C. (Least Concern). 2011.06.06.

Tree

There are no spines or thorns present on this unarmed Tree.  It has a spreading untidy crown and is usually 5-10 but may reach 15m high.  It often branches near the ground (photo 693).  The Trunk is often multi-stemmed. It may be crooked or forked close to the ground.  The Bark on an older trunk can be grey to brown, rough and longitudinal fissured.  Twigs (1-year-old current branch segments) are covered with rusty coloured hairs (photo 946).

Leaves

This tree may be deciduous.  The feathery, silvery grey Leaves are bipinnate (compound: twice pinnate. The central axis or rachis has lateral “branches” not leaflets and the leaflets are on these “side branches”) and end with a pair of Leaflets.  These small leaflets are usually about 7 x 2mm.  They are oblong and spaces apart.  Each is dull olive green above and paler green below. The Apex is rounded, with a fine, distinctive hair-like tip (photo 949).  The Base is asymmetric and the Margins are entire (with a continuous margin, not in any way indented but may be hairy).  Rusty brown, velvety Hairs envelope both the Petiole (leaf stalk) and Rachis.  The distinctive feather shaped Stipules (basal appendages of the petiole: photo 519) fall early.  The furry Growing tip is often rusty brown (photo 558).

Flowers

The sweet scented, very showy, bright yellow Flowers usually occur at branch ends in Racemes (a simple elongated inflorescence with stalked flowers that open in succession towards the apex). They often occur in dense axillary sprays that are 15+cm long. Each flower is bisexual, zygomorphic (irregular flower: when corolla is divisible into 2 equal halves in one plane only) and up to 2cm wide. The reddish brown Calyx (photo 148) is hairy and has a short bell-shaped tube with 5 lobes that are longer than the tube. The Corolla has 5 bright yellow, crinkled Petals. These Petals are all almost the same size – about 2cm in both diameter and length. None are joined to form a keel as in the sweet-pea type flower. There are 10 free, declinate (bent downward or forward, the tips often recurved) Stamens. Long soft hairs cover the base of the Filaments. The Anthers are versatile (hung or attached near the middle usually moving freely) and open through longitudinal slits (photo 151). There is a single Pistil (a unit of the Gynoecium, the female element of the flower, composed of the Ovary, Style and Stigma). Here the superior Ovary contains 1 locule. The single Style ends with a broad, shield-shaped Stigma (green in photo 155). Reddish brown, velvety hairs cover both the Pedicel (flower stalk) and the Sepals. Bees are probably responsible for Pollination (Sep-Feb).

Fruit

The flattish, drooping and indehiscent Fruit is a Pod which is elliptic (oval in outline and widest near the middle) to oblong. The pods taper toward both the apex and base. A distinct wing is visible along both margins. The remains of the Calyx may be visible at the base of the fruit (photo 689). Each fruit is up to 10 x 2cm. It is thinly woody, slightly leathery and green to yellowish becoming red-brown. Fruit hangs down in clusters. Seeds are brown and flattish, and about 11 x 7mm. Usually 1 or 2 seeds develop in each fruit. (Aug-Feb).

Distribution & Ecology

These Trees are located in KwaZulu-Natal, Gauteng, Mpumalanga, Limpopo and North West. They are also found in Botswana, Namibia, Angola, Swaziland, Mozambique, Zimbabwe, Zambia, Tanzania, Kenya and DRC. Major habitat: medium altitude: Grassland Savanna – Bushveld, Woodlands, on rocky outcrops, on riverbanks and on sandy soil. Larvae of the butterfly Satyr Emperor (Charaxes ethalion) and of Van Son’s Emperor (Charaxes vansoni) feed on the Leaves. Game including giraffe, elephant, and kudu browse the leaves. Black rhino strip and consume the Bark. After the start of the rainy season, plant-sucking nymphs of spittle bugs (Ptyelus grossus) encase themselves in protective acrid foam froth and cause some trees to “rain”.

Ethnobotany

The soft, close grained, fairly hard and tough Wood has reddish heartwood (photo 635). It is suitable for carving after seasoning. The seasoning is necessary to prevent borer attack. After seasoning, it can also be used for furniture. The wood is used for fuel. It is a good garden and shade tree. The plant grows quite quickly from seed and is slightly resistant to dry times and frost. Roots are non-invasive. The Fruit is used for feeding goats and cattle. Cattle eat the Pods. The Gum may be poisonous.

References

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

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

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.

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

http://redlist.sanbi.org/species.php?species=453-1

http://www.plantzafrica.com/plantnop/peltophorumafricanum.htm

https://en.wikipedia.org/wiki/Peltophorum_africanum

http://www.zimbabweflora.co.zw/speciesdata/species.php?species_id=127220

http://operationwildflower.org.za/index.php/plant-records/trees/118-peltophorum-africanum

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