Peltophorum africanum (SA Tree No: 215) is a semi-deciduous to deciduous, drought-resistant, small to medium-sized tree with lovely fine, feathery leaves which resemble those of our wonderful Vachellia (previously Acacia) species, but the African Wattle is devoid of thorns.

It goes by numerous common names, including: Weeping Wattle, African Black Wattle, African Blackwood, African Wattle, Boerboon, Boerboontjie, Dopperkehatenhout, Dopperkiaat, Kajatenhout, Rooikiaat, Witkiaat, Huilboerboom, Huilboom, Huilwattel, Wildewattel, Isikhabamkhombe, Umsehle, Umthobo, Mosehla, Mosêhla, Mosese, Motlêpê, Mosêtlha, Musese, and Ndzedze.

Common names like Weeping Wattle or Huilwattel do not refer to its growth habit, but rather to a phenomenon that occurs in spring just before the first rain, when moisture drips from the branches of some of these trees. This is caused by nymphs of small frog-hoppers or spittle-bugs (Ptyelus grossa) that suck up the sap of the trees and excrete almost pure water, which drips to the ground.

Click on highlighted text to see Google images of spittle bugs.

The African wattle is a plant of the moist lowland tropics and subtropics, where it is found at elevations up to 1 000 metres. It is widely distributed in tropical and subtropical Africa, growing wild in DR Congo, Angola, Zambia, Botswana, Malawi, Swaziland, Mozambique, Zimbabwe, Zambia, Namibia, Tanzania, and Kenya. In South Africa it is not a threatened species, and is found in Limpopo, North West Province, Gauteng, Mpumalanga, and KwaZulu-Natal. It is cultivated in Kenya, Tanzania, Madagascar, Australia and the United States.

It grows on very poor, acidic, sandy, and loamy to gravelly soil derived from sandstone, quartzite or shale and is also found on shallow soils on norite, granite and laterite, favouring medium to low altitudes. The trees are commonly found growing in grassland savanna scattered with shrubs and isolated trees, which can be found between a tropical rainforest and desert biome. Trees also occur at low to medium altitudes in bushveld, deciduous woodlands, on rocky outcrops, riverbanks and the margins of vleis.

In moist, tropical regions the African wattle can attain a great height of about 15m, but generally it grows anything between 4 to 8m tall, depending on climate and rainfall. The tree develops a spreading, open crown, and is frequently branched from near the ground. The bark of young branches is smooth and grey, but in older trees the bark becomes grey-brown and rough, with longitudinal fissures that provide a habitat for tiny insects that shelter in the crevices.  The bark, together with the hairy leaf and flower buds add to the beauty of this tree.

From mid to late summer (October to May), a profusion of crinkly, bright yellow flowers appear, held well above the leaves on long spikes 15cm long, and this is when the tree is really lovely. The nectar of the flowers attracts many insects, birds and butterflies to the garden, making the African wattle indispensable in wildlife gardens. The flowers are followed by dense clusters of thin, flat, dark brown pods about 10cm long, and they hang on the tree for months before being dispersed by the wind.

Click here to see Google images of the African wattle tree.

Peltophorum africanum Lows Creek Mpumalanga. Picture courtesy Alexey Yakovlev from FlickrUses:

The African wattle is an extremely valuable tree with many uses. In rural areas it is an invaluable shade tree for both humans and livestock, and the young leaves and pods are browsed by livestock and game like giraffe, elephant and kudu. Because the flowers are so rich in nectar, this tree is essential for bee-keeping. The timber is good for fuel and because it has heavy, fine-textured, interlocked-grain, after seasoning it works fairly easily, takes a good polish, and produces a smooth finish. The wood is used for carving, turning, making furniture, grinding blocks, wooden buckets, tool handles etc. It is not suitable for fence poles or buildings as it is not borer-proof.

Local people consume the large green spiny lava of the moth Gynanisa maja which feeds on the leaves.  The adults are on the wing from mid-December to early February.

Click on highlighted text to see Google images of the moth and larvae.

The bark, roots and leaves of the African wattle are commonly used in traditional medicine, and there are very many medicinal uses recorded, from treating sore eyes to digestive disorders. Modern research is ongoing and this tree and has shown the presence of several medically active compounds. This is a vast subject, so if you are interested in learning more about the medicinal uses of this tree you will have to do your own research.

In the Garden:

Its rounded shape, beautiful flowers, and ability to grow in sun on semi-shade, makes the African wattle a good shade tree in the smaller garden, and it has a beautiful architectural form when leafless. The roots are generally not aggressive but it’s best to have a safe planting distance of at least 5m from any structure.

The African wattle is wonderful in a wildlife-friendly garden, and a host tree for butterflies. Larvae of the following butterflies feed on the leaves: Van Son's charaxes (Charaxes vansonii), Satyr Charaxes (Charaxes ethalion) and Braine's Charaxes (Charaxes brainei)

Click on highlighted text to see Google images of these butterflies.

The nectar-rich flowers are ideal for beekeepers, and also attract birds. The tiny insects that shelter in the crevices of the bark attract birds like Red Billed Wood Hoopoes that stick their long, pointed beaks into the crevices to harvest their prey.

Interestingly, the African wattle is associated with termite mounds, and the dominance of this species in the vegetation is taken as an indication of a high level of arsenic in the soil, and indirectly, this may indicate the presence of gold.

The plant's tolerance to adverse soil conditions makes it a candidate for reclaiming denuded sites such as abandoned mines and mine dumps.

The African wattle is very versatile and is used in many garden styles, including: bushveld, country, grassland, rockery, and woodland gardens. It makes a good avenue tree and is wonderful planted alongside rivers, streams and dams. It is also popular as a bonsai tree.

Cultivation/Propagation:

This tree loves full sun but is able to grow in light shade. Young trees transplant readily, and are fairly fast growing, with a growth rate between 1 to 1.5 metres per year, if they are watered regularly.  

Naturally the African wattle thrives in tropical and subtropical regions, growing best in areas where the annual daytime temperatures are within the range of 20 to 32°C, but can tolerate ranges between 16 to 38°C. The trees can tolerate light to moderate frost once established. In cold regions the tree will drop all its leaves and become dormant in winter, and in this state the plant will not require watering, and can survive temperatures down to about -4°C, but young growth can be severely damaged at -1°C. Therefore, young trees need to be protected in winter for the first couple of years, and do best if planted in a sheltered place, away from freezing winds.

In the wild this tree grows on very poor, acidic, sandy or loamy to gravelly soil derived from sandstone, quartzite or shale and is also found on shallow soils on norite, granite and laterite, but grows best in a well-drained, sandy to loamy soil of moderate fertility, and a pH in the range of 5.5 to 7.  In the garden it adapts to most, well-drained soils, and the addition of some compost and fertiliser won’t harm.

The trees are reasonably drought resistant once established, but prefer a mean annual rainfall in the range 1,000 to 2,500mm, but tolerate 700 to 3,000mm annually.

After cutting the tree coppices readily, and if you cut higher, it will have a strong positive effect on the number of new shoots.

The African wattle is grown from seed, which stores well, and viability is maintained for up to 3 years if the seed is stored in a dry place at room temperature. Seeds germinate easily and young plants transplant well.

The seed has a hard seed-coat and may benefit from scarification before sowing to speed up germination. This can usually be done by pouring a small amount of very hot, but not boiling water over the seeds and soaking them for 12 to 24 hours in warm water. At this stage they should have imbibed sufficient moisture to appear swollen. If they have not swollen, carefully make a nick in the seed-coat (being careful not to damage the embryo) and soak for a further 12 hours before sowing. Sow into deep seedling trays filled with a growing mixture of 5 parts washed river sand to one part compost. Germination will occur within a week or so, and the germination rate is usually high.

Problems, Pests & Diseases:

The African wattle is relatively free from pests and diseases.

After the start of the rainy season, plant-sucking nymphs of Spittlebugs (Ptyelus grossus) may encase themselves in protective acrid foam froth and cause this and some other trees to “rain”.

The larvae of the moths Aurivillius arata and Alpenus investigatorum (synonym: Diacrisia investigatorum) feed on the leaves of Peltophorum africanum. The larvae of several Charaxes butterflies also feed on the leaves.

Warning:

The gum may be poisonous.