Weeping Boer-Bean: Schotia brachypetala

#LoveYourCampus - Interactive Botanical tour

Point No. 16

Species: Schotia brachypetala Sond.

Family: Fabaceae

Common names: weeping boer-bean, drunken

parrot tree, huilboerboon, umfofofo, ishimnumyane

 

This impressive Schotia brachypetala individual came to be on our very own Hatfield campus approximately 60 years ago! The specimen was planted by Professors Theron and Robbertse and still stands before us today in the Rainwater Harvesting Garden after surviving at least two landscape redesigns since the 1960’s.

 

Distribution

S. brachypetala is no stranger to the warm and dry habitats of the eastern provinces of South Africa. In fact, the endemic southern African tree has a wide mid-altitude distribution stretching from the Eastern Cape, all the way up to Mozambique and Zimbabwe (south of the Zambezi River). It is commonly found on stream banks or old termite mounds within woodlands, shrub forests, and especially in bushveld areas where it is known for its attractive appearance¹.

 

Morphology (form and structure)

The weeping boer-bean is characterised by

having a wide-spreading (10 - 15 m) rounded crown with a dense system of branches, with each branch ending in a decorative mass of bright red flowers. It is a medium to large tree able to reach heights of 22 m. In areas with colder climates, the tree is deciduous, losing its leaves in winter, while it is usually evergreen in warmer areas.

 

The compound leaves, with 4 to 6 pairs of leaflets and a wavy margin, are a dark glossy green when mature, but a reddish-coppery colour when young. The masses of flowers produced are a deep red colour and occur in clumps in Spring from August to November, however, the exact flowering time of each tree is variable from year to year. The flowers produce massive amounts of sweet nectar, so much so that the ground below the tree is often wet and sticky with it. These flowers give way to hard, flattened, woody pods containing large pale brown seeds. These mature in late summer and split open whilst still on the tree, releasing their seeds for dispersal. The large seeds that are produced are edible and fairly nutritious with a high carbohydrate content. The seeds have a conspicuous yellow outgrowth called an aril that serves as a nutritious reward for birds to disperse the seed. The Khoikhoi people had first discovered that the seeds could be eaten after being roasted, which is now commonly practised throughout the world today.

 

Taxonomy

The small Schotia genus (family: Fabaceae, subfamily: Caesalpinioideae) made up of only 4 species, was named after the gardener and botanical painter, Richard van der Schot. More specifically, the name ‘brachypetala’ is derived from the Greek phrase ‘having short petals’. Its linear filament-like petals set this unique species apart from other Schotia trees. You may also be wondering how this tree acquired the fascinating ‘weeping boer-bean’ nickname. Interestingly enough, this is due to the overflowing flower nectar that drips down its branches during flowering - it looks almost as if the tree is crying. The tree also shares a striking resemblance to the original broad bean that is popularly used in agricultural practices².

Leaves (by Anna Kotschy), flowers (by Richard Johnstone, iNaturalist), and seed pods (by Vilanet, iNaturalist) of S. brachypetala.

Ecology

When flowering, S. brachypetala attracts a plethora of wildlife. Nectar-feeding birds and insects feed on the copious amounts of nectar, and insect-eating birds are attracted by the insects. Parrots in particular have developed such a liking to the flower’s by-products that their excessive ingestion of the

 

fermented nectar can cause them to get drunk! Mammals like monkeys, baboons, and squirrels eat the whole flowers as well as the seeds that fall onto the ground. Larger browsers eat the leaves and some, like black rhino, even eat the bark. The irregularity of the trees’ flowering times ensures a longer feeding season for these many animals that depend on them. Although these trees are not threatened, it is essential that we protect them and their many ecosystem services. Accelerated removal of the trees could possibly lead to a drastic loss of biodiversity and the collapse of important food chains.

Uses

One would not expect a tree to have the extensive variety of benefits that this one has. Its attractive shape and flowers have made it a popular ornamental plant for landscaping in horticulture. Its bark has been used as a red/brown dyeing agent. Medicinal uses include the treatment of heartburn, nervous heart conditions, diarrhoea and even hangovers using a decoction of the bark and/or roots. Historically, the wood was said to be excellent for wagon-building and in more recent times, it can be used to make furniture and flooring since its hardwood is termite-resistant³.

 

Remember that you can also find out more about the captivating Schotia brachypetala species by visiting a preserved 1986 specimen at UP’s H.G.W.J. Schweickerdt Herbarium on Hatfield campus!

 

Cited sources:

1 Mbambezeli, G & Notten, A. (2014). Schotia brachypetala. [Online]. Available from: http://pza.sanbi.org/schotia-brachypetala.

2 Siyabonga Africa. (2022). Weeping Boer Bean. [Online]. Available from: https://www.krugerpark.co.za/africa_weeping_boer_bean.html.

3 Witkoppen Wildflower. (2019). Schotia brachypetala. [Online]. Available from: https://witkoppenwildflower.co.za/schotia-brachypetala/

 

Images:

Richard Johnstone, iNaturalist, https://www.inaturalist.org/observations/175284392

Vilanet, iNaturalist, https://www.inaturalist.org/observations/161981712

Anna Kotschy and Bradley Fulcher

 

Text prepared by Anna Kotschy and Bradley Fulcher, 2022 BOT 366 class.