General Info – summary

This upright, dioecious & usually up to 9m high, Tree has high, stout branches and a large environment impact.  The deciduous Leaves are imparipinnate and become entire and hairless.  Male Flowers in racemes with up to 25 stamens.  Usually, solitary female flowers on pedicels have a superior ovary + short styles ending with a peltate stigma.  Fruit is a fleshy drupe – smells when ripe and contains up to 3 seeds.

Description

Sclerocarya birrea subsp. caffra

Previous Names: Commiphora subglauca, Sclerocarya caffra, Sclerocarya schweinfurthiana.

SA Tree No. 360.

Common names: (Afr) Maeroola, Maroela, Maroelaboom, Moroelaboom.  (Eng) Cider Tree, Maroola, Marula.  (isiZulu) Umganu.  (Northern Sotho) Morula.  (Setswana) Morula, Ankanyl, Nkanyi.  (siSwati) Umganu.  (Tshivenda) Mufula.  (Xitsonga) Ankanyi.

Family: Anacardiaceae (Mango family), which has about 83 genera and 850+ species – including Cashew).  Resin canals are present and woolly stellate hairs cover all young parts.  Leaves lack stipules.  They may be deciduous or evergreen and usually alternate.  Leaves are simple, trifoliate or digitally compound and imparipinnate.  Leaflets are usually opposite.  Crushed leaves may smell of turpentine.  Trees are monoecious or dioecious with occasional bisexual Flowers.  Flowers are small, usually regular.  The Calyx has 4-7 sepals and there are 4-7 Petals.  The number of Stamens is the same as, or twice the number of petals and the Anthers are versatile.  The superior Ovary has up to 4 locules, each with a single ovule.  The 1-5 Styles are free or connate and separated at the base.  Fruit is usually an indehiscent fleshy drupe with a single Seed.  The southern Africa genera containing trees on this website include Harpephyllum, Lannea, Loxostylis, Ozoroa, Sclerocarya and Searsia.

Name derivation: Sclerocarya – hard nut: referring to the fruit kernel (a softer, often edible part of a nut, seed, or fruit stone contained within its hard shell).  birrea derived from the common name in Senegal.  birrea is the only species of the genus Sclerocarya in southern Africa.

Conservation Status: L C. (Least Concern).  Assessment: 2008 (V.L. Williams, D. Raimondo, N.R. Crouch, A.B. Cunningham, C.R. Scott-Shaw, M. Lötter, A.M. Ngwenya and C. Helm).  Because of its provision of shade and fruit, indigenous people protect and preserve this tree.

Tree

This relatively large Tree, with its spreading rounded and shady Crown (photo 462) is usually up to 9m but may reach 17m high.  It has an erect smooth Trunk with a diameter of up to 1m.  The Bark is light grey-brown and peals in patches leaving round depressions and gives a mottled appearance (photo 463).  This may expose the yellowish underbark.  In mature trees, the stout thick Branches occur high up (photo 953).  They end abruptly in blunt finger-like tips.  This feature is distinctive in winter after the leaves have fallen.  Leaf scars are visible on the young stem (photo 357 – under Leaves).

Leaves

This deciduous tree is leafless for several months each year and eventually develop graceful Leaves that are crowded towards the ends of branches.  The leaves are alternatively arranged but not sickle-shaped.  Young leaflets are reddish/copper coloured and curved along the line of the midrib (photo 117).  Leaves are imparipinnate (pinnately compound leaf ending in a single Leaflet – photo 337) and up to 38cm long.  The Rachis (main axis bearing flowers or leaflets), including the up to 5cm long Petiole (leaf stalk) may be tinged with pink (photo 337).  In addition to the single terminal leaf, there are 3-7 pairs of hairless, widely spaced opposite or nearly so Leaflets (photos 341 & 337).  Leaflets are ovate to elliptic and each is up to 10 x 4cm – usually less (photo 337) with Margins that are only toothed when young and on coppice growth (when stems are cut or burned it causes regrowth from the base or roots).  Mature leaflets are entire (with a continuous margin, not in any way indented).  The Apex is initially broadly tapering and finally acuminate (said of an acute apex whose sides are somewhat concave and taper to a protracted point – photo 341).  The Base is slightly asymmetric (not equal on both sides – photo 337) and is broadly tapering to rounded.  The Blade of mature leaves is shiny dark green above, blue-green, and lighter below and the midrib is ridged on both sides.  The slender, non-winged Petiole is up to 5cm long (photo 337).  Petiolules (leaflet stalks) are distinctive.  On lateral leaflets, they are slender and up to 3cm long (photo 337).  The petiolule of the terminal leaflet may be slightly longer.  Leaves turn yellow before falling.

Flowers

These trees are dioecious (unisexual floral structures with male and female parts on separate plants).  Occasionally bisexual Flowers develop.  Flowers develop in leaf axils or at the ends of branches (photo 81) and appear before or with the new leaves.  The buds are a deep red (photo 358).  They open to a pinkish white (photo 352).  The Calyx consists of 4 or 5 reddish Sepals.  The Corolla has 4 or 5 yellow, curling Petals.  Both the sepals and petals are imbricate (having regularly arranged).  The Disc (a more or less fleshy or elevated development of the receptacle) is entire, depressed or slightly raised in male flowers.

The Male flowers develop in a terminal Raceme (a simple, unbranched, indeterminate inflorescence with individual flowers on their own Pedicel – flower stalk (photo 358).  The flowers open in succession towards the apex).  This occurs on a single unbranched axis that is up to 8cm long.  Each flower has 15-25 Stamens with Anthers that are versatile (hung or attached near the middle, and usually moving freely – photo 354).  In the male flowers, the ovary is undeveloped.

The Female flowers have pedicels (flower stalks) and are solitary or in small groups.  15-25 staminodes (sterile stamens) are present in each flower and the superior Ovary is almost spherical.  A single pendulous Ovule occurs in each locule.  The short (2 to 4) Styles each end with a peltate (shield-shaped) Stigma.  These flowers are insect pollinated.  (Sep-Nov).

Fruit

The spherical or oval shaped Fruit (photo 480) is a large, fleshy Drupe (a fleshy indehiscent fruit with the seeds enclosed in a stony endocarp; stone fruit e.g. peach) that is up to 5cm long.  The initially green fruit falls to the ground (photo 464) then ripens to a yellow colour.  The exocarp (leathery skin) is thick and covers the mesocarp (white fleshy part), which, in turn, covers the very hard endocarp (the woody stone – photo 480).  The fruit contains 1-3 Seeds each developing in its own chamber.  These are exposed when the 2-3 plug-like structures are removed.  Seeds have a thin brown Testa (seed coat).  Occasionally a male flower also develops into a fruit.  The ripe fruit is leathery, covered with spots and smells of turpentine.  Decaying fruit has a strong smell.  Seed Dispersal is by animals and even by water.  (Dec-Mar).

Distribution & Ecology

This plant grows in different soil types and is found in the bushveld and woodlands of KwaZulu-Natal, Mpumalanga e.g. southern Kruger National Park, Northern Gauteng, Limpopo and North West.  It also grows in SiSwati (Swaziland), Mozambique – widespread, Botswana, Kenya, DRC, Namibia, Angola, northwards, as well as Madagascar.  The tree develops best in warm, frost-free areas at low to medium altitudes (from sea level to about 1 500m) and is moderately salt tolerant.  The Flowers attract many insects.  Fallen Fruit – often not initially ripe (photo 464 above), is consumed by elephants, monkeys, baboons, rhino, porcupines, warthogs, squirrels, antelope and Zebra.  The fruit may have an intoxicating effect on the animals.  Parrots, with their exceptionally strong beaks, break the single very hard stone for the kernels (a softer, often edible part of a nut, seed, or fruit stone contained within its shell).  Butterfly larva feed on the Leaves.  Many animals consume the leaves.  Larvae of the giant silk moth or African moon moth (Argema mimosae) feed on the leaves and may defoliate the tree.  This green moth can reach 12cm across its wings and are up to 14cm long.   Nyala, Kudu and Giraffe also graze the leaves.  Impala eat fallen leaves and Elephants browse leaves and consume the Bark and Roots.

Ethnobotany

This is a protected tree in South Africa.  The Fruit is edible, sweet-sour, and thirst quenching.  It is used to make a strong alcoholic drink: e.g., a milky liqueur called Amarula is produced commercially.  Raw fruit is edible.  In the 1 000 year old Limpopo site in Mapungubwe National Park (now a world heritage site) the remains of the fruit have been found indicating its consumption by earlier inhabitants.  The fruit is used in making amber coloured jelly.  Fruit has a high protein and fat content.  People consume the Gonimbrasia belina caterpillars (mopani worms) that mainly feed on the leaves of this plant.  These caterpillars contain vital magnesium and calcium.  This edible caterpillar thus provides valuable food for the local people.  The Kernels (a softer, often edible part of a nut, seed, or fruit is contained within its shell) are rich in protein and have a much greater concentration of vitamin C than oranges.  Kernels are difficult to remove but can be ground and added to soups and food.  The Oil has preservative qualities and may be used to keep meat for up to 1 year.  Hollows in the tree act as a breeding ground for mosquitoes.  These hollows hold up to 2 litres of water.  Other trees that attract mosquitoes include Combretum imberbe, Senegalia nigrescens and Adansonia digitata (baobab).  The Wood is light red, has a low density and is soft.  Fungi and beetle attacks may discolour the wood.  The wood turns and takes nails well.  It has been used in flooring, drum making and for fuel.  Rope is made from the inner bark.  Bark also provides a light brown dye.  Leaf juice may stain clothing.  This tree grows easily from Seeds and from cuttings planted in early spring.  It grows fairly quickly but is frost sensitive.

References

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

Burrows, J.E., Burrows, S.M., Lotter, M.C. & Schmidt, E. 2018. Trees and Shrubs Mozambique.  Publishing Print Matters (Pty) Ltd.  Noordhoek, Cape Town.

Bryant, C. Lombo, B. 2004. Trees of CC Africa. Double Story Books, Cape Town.

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. Jacana, Johannesburg.

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

Williams, V.L., Raimondo, D., Crouch, N.R., Cunningham, A.B., Scott-Shaw, C.R., Lötter, M., Ngwenya, A.M. & Helm, C. 2008. Sclerocarya birrea (A.Rich.) Hochst. subsp. caffra (Sond.) Kokwaro. National Assessment: Red List of South African Plants version 2020.1. Accessed on 2023/11/28.

 

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

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

http://plantzafrica.com/plantqrs/sclerobirr.htm

http://www.worldagroforestry.org/treedb2/AFTPDFS/Sclerocarya_birrea_ssp._caffra.pdf

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

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

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