In celebration of Arbor Week

Trees of the year for 2022

 

Text and photographs Richard Boon

Arbor Day originated in 1872 in the United States of America when a Mr J Sterling Morton persuaded the local agricultural board to set aside a day for planting trees in the then treeless plains of Nebraska. Since then the celebration of tree planting has spread throughout the world and in South Africa Arbor Day was first celebrated in 1983 and each year one tree was selected to be “the tree of the year”. This tradition has continued and from 1996 at least two different Trees of the Year are nominated annually by the Department of Forestry, Fisheries, and Environment. One tree being a relatively common one whilst the second being somewhat “rare” or “uncommon” species. This was done to promote some of the lesser known species.

The event was well received by society as a whole and in 1999 the event was extended into Arbor week which falls in the first week of September each year.

National Arbor Week creates an opportunity for all South Africans to plant and celebrate indigenous trees as a symbolic gesture of our commitment to a sustainable environment.

In this article we review the “Trees of the Year for 2022”.

Dais cotinifolia Pompon Tree – 2022 Common Tree of the Year

Dais cotinifolia flowers

The Pompon Tree or Dais cotinifolia is an attractive small to medium tree and one of only two species in the genus Dais; the other is the Madagascan D. glaucescens. The genus Dais is part of the cosmopolitan plant family Thymelaeaceae, which includes about 50 genera and nearly 900 species. Most family members are shrubs or trees and there are about 200 species in South Africa, which is a centre of diversity for the group. Other local representatives include Gnidia, Lasiosiphon, Passerina and Peddiea. The family Thymelaeaceae is named after the genus Thymelaea which combines the Greek words for thyme and olive. Daphne and a few other species are grown as ornamentals. One way to easily recognise family members is that the bark peels in long strips when a branchlet is removed. The strips have been used for making whips, rope and for binding. It is for this feature that the family is called the Fibre-bark Family.

The scientific name Dais cotinifolia was first published by Carl Linnaeus in his second edition of Species Plantarum in 1762. Dais is a Greek word which means a pine-torch and refers to the resemblance of the inflorescence to an unlit torch. The species name cotinifolia was chosen because the leaves are similar to plants in the unrelated Northern Hemisphere genus Cotinus whose members are known as smoketrees or smokebushes.

The English common name is sometimes spelt Pompom Tree, but pompon is the original French spelling for the decorative balls found on hats. The Afrikaans common name is kannabas. Kanna is an indigenous name for Scletium and was incorrectly applied to D. cotinifolia. The correct word is gonna which is a collective Khoisan name for several members of the family. It is the origin of an alternative common name for the family used in South Africa, namely the Gonna Family. The Zulu name is intozwane emnyama. Intozwane is used for various shrubs in the family whose bark are used for fibre and emnyama means black.

The Pompon Tree is found in south-east tropical and sub-tropical Africa from the Eastern Cape to Malawi and Tanzania. It is a common species and is considered Not Threatened in South Africa. In KwaZulu-Natal it occurs in the Midlands and Drakensberg Mountains. Like many tree species, its distribution in the southern part of its range includes coastal regions, but in the north it is found at higher altitudes. It is not found in the Krantzkloof Nature Reserve and is not native to the eThekwini Metropolitan Area.

Dais cotinifolia at Monks Cowl

D. cotinifolia is a small tree which reaches 7 m (occasionally up to 12 m) but usually less in cultivation. In KwaZulu-Natal it inhabits cool inland forests, valley bushveld and may be seen in bush clumps on rocky hillsides. Depending on growing conditions, it may be evergreen or deciduous with leaves yellowing before falling. Leaves are arranged in pairs, are relatively large, have pale or translucent veins and a waxy feel. They often have a bluish-green tinge and are paler on the underside. Healthy specimens produce masses of pink pompon-like flower clusters. These are seen mostly in November and December in KwaZulu-Natal. Individual flowers have cylindrical tubes at the base with five lobes at the top. Petals are absent and the petal-like lobes are actually sepals. In most flowering plants sepals are green. The four green sepal-like parts in this species are bracts. The flowers are fragrant at night and probably attract moths given their shape and scent. Individual plants bloom for a short time. Blossoms apparently last well in water but I would leave them on trees for pollinators to enjoy. Seeds are small nutlets and are hidden in the dried flower remains which persist on the plants for a long time.

Dais cotinifolia – flower detail

Its small size, rounded crown and eye-catching inflorescences make the Pompon Tree a good garden plant. It is sometimes used as small street tree. It has been cultivated in Europe since the 1700s. Pompon Trees do best in full sun. Plants are apparently easily grown from seed and flower when young. Specimens can be kept bushy by tip pruning lightly after flowering. Plants growing in coastal parts of Durban often struggle, although I have seen a few nice specimens. I suspect Pompon Trees will do much better in Kloof and surrounding suburbs.

Peltophorum africanum African or Weeping Wattle – 2022 Rare Tree of the Year

The African or Weeping Wattle is one of seven similar tree species in the tropical genus Peltophorum. It is the only species native to Africa. Other members are found in the Caribbean, South America, Asia and Australia. Peltophorum is part of the Caesalpinioideae sub-family of the large legume family Fabaceae. Alternative classifications recognize the sub-families as families. Other members of the Caesalpinioideae that may be well-known to readers are the Boer-beans Schotia species, Bauhinia species, Senna and Cassia species and the Madagascan endemic Delonix regia or Flamboyant.

The genus name Peltophorum comes from the Greek pelte = shield and phorein = bearing. The name refers to the shape of the stigma which is at the tip of the female part of the flower and is the pollen receptor.

The English common name African or Weeping Wattle is misleading. Most plants called wattles are Australian Acacia species and, along with African acacias (now classified in the genera Vachellia and Senegalia), are in a different legume sub-family, the Mimosoideae. The word wattle comes from the use of certain trees and shrubs to make wattle and daub huts. The wattles were the woven panels that were daubed with mud and then dried. Peltophorum pterocarpum, which grows naturally from Asia to northern Australia, is sometimes grown as a street tree in Durban. It is known by various common names, e.g. Copperpod, Yellow Flame-tree and Yellow Flamboyant.

On occasion Peltophorum africanum trees may ‘weep’ due to infestations of spittlebugs. The bugs suck plant sap through their piercing mouth parts and excrete copious amounts of harmless processed fluid, which falls like rain or tears. This gives P. africanum its English name Weeping Wattle and its Afrikaans name huilboom. Several species of tree are commonly afflicted by spittlebugs and are collectively called rain-trees. While the sap suckers probably stress trees a little, I don’t think they are harmful enough to do serious damage. Marlies Craig wrote an interesting article on spittlebugs for Leopard’s Echo which readers can find here – The soggy existence of the rain tree bug.

The Zulu names are umsehle, umthobo and isikhaba somkhombe. Umthobo can mean ‘poultice’ or ‘fermentation’ and may refer to the plant’s many medicinal uses. The derivations of the other names are less clear.

The range of P. africanum is from the Democratic Republic of Congo in the north to about Hluhluwe-iMfolozi Park in the south. In Zululand it is found in bushveld savanna. It is a common species and is considered Not Threatened in South Africa.

Peltophorum africanum at Kube Yini Private Game Reserve

The African Wattle is a small to medium-sized, deciduous tree which reaches about 10m in height. It superficially resembles an acacia species but lacks thorns and has characteristic fern-like stipules on the branchlets. The trunk often branches near the ground and the crown is rounded to spreading. Young parts are covered in rusty brown hairs. Leaves are feather-like or bipinnately compound which means they are twice-divided. The leaflets are small. It is very attractive in flower with abundant flowers held in erect spike-like racemes. The five crinkly petals are bright yellow. Flowering in KwaZulu-Natal is normally in December and January. Pods are produced in masses and persist on trees late into winter. They are flat, winged on both margins and covered in fine hairs.

Peltophorum africanum seed pods – uMkhuze Game Reserve

The roots and bark are used medicinally to treat a range of ailments including abdominal pain, nausea and venereal disease. The heartwood is dark and reddish- to purplish-brown and the sapwood is pale. It is used for small furniture items, turnery, carvings and firewood. The African Wattle is an attractive shade tree and is fairly quick-growing from seed. It has some resistance to drought and frost. As Durban is well south of the species’ normal bushveld range, cultivated plants are likely to do best in sunny positions on well-drained soil and shouldn’t require any water once established.

Acknowledgements

Thank you to Professor Adrian Koopman for advice on Zulu names.

References

Boon, R. [R.G.C.] (2010) Pooley’s trees of eastern South Africa. A complete guide. Flora and Fauna Publications Trust, Durban, 626 pp.

Dyer, S., James, B. & D. James (2016) Guide to the properties and uses of southern African wood. Briza Publications, Pretoria, South Africa, 336 pp.

Foden, W. & Potter, L. (2005) Dais cotinifolia L. National Assessment: Red List of South African Plants version 2020.1. (Accessed 1 April 2022)

Glen, H. (2004) Sappi what’s in a name. The meanings of the botanical names of trees. Jacana Media (Pty) Ltd, Johannesburg, 80 pp.

Koekemoer, M. Steyn, H. & S.P. Bester (2014) Guide to the plant families of southern Africa, edition 2. Strelitzia 31. South African National Biodiversity Institute, Pretoria.

PlantZAfrica. South African Biodiversity Institute. Available from pza.sanbi.org (Accessed 30 March 2022)

POWO (2019) Plants of the World Online. Facilitated by the Royal Botanic Gardens, Kew. Available from: http://www.plantsoftheworldonline.org/ (Accessed: 30 March 2022)

Van Wyk, B. & Van Wyk, P. (2013) Field guide to the trees of southern Africa, 2nd edn fully revised. Struik Nature, Cape Town, 732 pp.

Van Wyk, B-E & Gericke N. (2000) People’s plant a guide to the useful plants of southern Africa. Briza Publications, Pretoria, South Africa, 351 pp.

Von Staden, L. (2011) Peltophorum africanum Sond. National Assessment: Red List of South African Plants version 2020.1. (Accessed 3 April 2022)

WorldWideWattle ver. 2. Published on the Internet at: www.worldwidewattle.com (Accessed 10 April 2022)

Author photo: Pat McKrill

About the author

Richard Boon is well-known not only for his outstanding book Trees of Eastern South Africa – A Complete Guide but also for his environmental work at WESSA in the 90’s and later as part of the Environmental Planning and Climate Protection Department at eThekwini where he headed up the Biodiversity Planning Branch until end 2018. Richard is a practical botanist with over 25 years of field experience. He also enjoys photographing plants and other natural subjects. This article was written for The Leopard’s Echo from his new home in Melbourne, Australia. He currently works for the Victorian state government on native vegetation offset management. The role includes travelling statewide to visit new places and meet landowners. Work involves lots of learning and is much more field-based which has been a nice change. In his spare time, he learns the local ecology, flora and fauna.