Sclerocarya birrea ssp. caffra

Invasive species Disclaimer

In view of the fact that some tree species are invasive, the world Agroforestry Center (ICRAF) has put in place a policy document on Invasive Alien Species, currently under draft available at Here.

For more information on this subject, please refer to
100 of the World's worst Invasive and Alien Species.

Species Index    A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
Multiple Criteria Search

Abelmoschus moschatus
Acacia aneura
Acacia angustissima
Acacia aulacocarpa
Acacia auriculiformis
Acacia catechu
Acacia cincinnata
Acacia crassicarpa
Acacia elatior
Acacia erioloba
Acacia etbaica
Acacia ferruginea
Acacia glauca
Acacia holosericea
Acacia karroo*
Acacia koa
Acacia laeta
Acacia lahai
Acacia leptocarpa
Acacia leucophloea
Acacia mangium
Acacia mearnsii*
Acacia melanoxylon
Acacia mellifera
Acacia nilotica subsp nilotica
Acacia pachycarpa
Acacia pennatula
Acacia polyacantha ssp. polyacantha
Acacia saligna
Acacia senegal
Acacia seyal
Acacia sieberiana
Acacia tortilis
Acacia xanthophloea
Acrocarpus fraxinifolius
Adansonia digitata
Adenanthera pavonina
Aegle marmelos
Afzelia africana
Afzelia quanzensis
Agathis macrophylla
Agathis philippinensis
Ailanthus altissima
Ailanthus excelsa
Ailanthus triphysa
Albizia adianthifolia
Albizia amara
Albizia anthelmintica
Albizia chinensis
Albizia coriaria
Albizia ferruginea
Albizia gummifera
Albizia julibrissin
Albizia lebbeck
Albizia odoratissima
Albizia procera
Albizia saman
Albizia versicolor
Albizia zygia
Aleurites moluccana
Allanblackia floribunda
Allanblackia stuhlmannii
Allanblackia ulugurensis
Alnus acuminata
Alnus cordata
Alnus japonica
Alnus nepalensis
Alnus rubra
Alphitonia zizyphoides
Alstonia boonei
Alstonia congensis
Alstonia scholaris
Altingia excelsa
Anacardium occidentale
Andira inermis
Annona cherimola
Annona muricata
Annona reticulata
Annona senegalensis
Annona squamosa
Anogeissus latifolia
Anthocephalus cadamba
Antiaris toxicaria
Antidesma bunius
Araucaria bidwillii
Araucaria cunninghamii
Arbutus unedo
Areca catechu
Arenga pinnata
Argania spinosa
Artemisia annua
Artocarpus altilis
Artocarpus camansi
Artocarpus heterophyllus
Artocarpus integer
Artocarpus lakoocha
Artocarpus mariannensis
Asimina triloba
Ateleia herbert-smithii
Aucomea klaineana
Averrhoa bilimbi
Averrhoa carambola
Azadirachta excelsa
Azadirachta indica
Azanza garckeana
Related Links
S. birrea seeds after extraction
© James Were
S. birrea bark.
© Roeland Kindt
Variation in fruit colour.
© Jumanne Maghembe
Sclerocarya birrea leaves
© Joris de Wolf, Patrick Van Damme, Diego Van Meersschaut
Sclerocarya birrea flowers
© Joris de Wolf, Patrick Van Damme, Diego Van Meersschaut
Sclerocarya birrea fruits
© Joris de Wolf, Patrick Van Damme, Diego Van Meersschaut
Seed extraction from S. birrea, Namibia
© James Were
Nursery stock from range-wide collection in southern Africa in Zomba, Malawi
© Anthony Simons
Sclerocarya birrea
© Patrick Maundu
Sclerocarya birrea fruits
© Patrick Maundu
Young Sclerocarya birrea ssp. caffra in northern Namibia.
© Martien Gelens
Sclerocarya birrea ssp. caffra
© Anthony Njenga

Local names:
Afrikaans (maroela), Arabic (el hamaidai,homeid), Bemba (musebe), English (marula), Hausa (dania), Lozi (muyombo,muongo,mulula), Nyanja (msewe,mgamu), Swahili (mng'ong'o,mng' ongo,morula,mgongo), Tigrigna (abengul), Tongan (muongo), Trade name (marula),

Sclerocarya birrea ssp. caffra is a medium to large tree, usually 9 m tall, but trees up to 18 m have been recorded; it is single stemmed with a dense, spreading crown and deciduous foliage; the bark is grey and usually peels off in flat, round disks, exposing the underlying light yellow tissue; young twigs are thick and digitaliform with spirally arranged composite leaves at their ends; it has a thick, relatively short taproot reaching depths of 2.4 m, lateral roots branch at the upper 60 cm of soil; mycorrhizae (root fungus) are found on the fine roots.

Leaves 18-25 x 8-15 cm, composite, containing 2-23 leaflets, averaging 11; leaflets oblong elliptic with petioles ranging from very short to 20 mm in length. 

Although male and female flowers occasionally occur on the same tree, it is considered dioecious. Male flowers are borne in groups of 3s on racemes below new leaves, dark red when young, turning pink or white when open. The female flowers are blood red but change colour from purple to white after opening. They occur below the leaves on long peduncles and consist of 4 curling petals, numerous infertile stamens and a long, shiny ovary. 

Fruit borne in clusters of up to 3 at the end of the twigs and always on the new growth. Fruit a round or oval drupe, usually wider than it is long, with a diameter of 30-40 mm. The shape and number of nuts per stone determine the final shape of the fruit. Marula fruit has a thick, soft leathery exocarp with tiny, round or oval spots, enclosing a juicy, mucilaginous flesh that adheres tightly to the stone and can be removed only by sucking. The flesh tastes tart, sweet and refreshing, although the fruit has a slight turpentine-like aroma and can give off a very unpleasant smell when decaying. Each fruit contains an exceedingly hard seed, which is covered by fibrous matter. It is usually trilocular, but sometimes only bilocular. Each seed locule contains a single, light nut filling the entire cavity, which is sealed by a round, hard disk that protects the embryo until germination.

The name ‘sclerocarya’ is derived from two Greek words, ‘skleros’ and ‘karyon’, meaning ‘hard’ and ‘nut’, respectively, and refers to the hard stone of the fruit. ‘Birrea’ comes from ‘birr’, the common name for the tree in Senegal, and caffra from ‘Kaffaria’ (Eastern Cape, South Africa).


S. birrea ssp. caffra occurs in wooded grassland, riverine woodland and bushland and frequently on or associated with hills. It prefers a warm, frost-free climate but is also found at high altitudes where temperatures may drop below freezing point for a very short period in winter. The tree is frost sensitive and moderately drought resistant. Occasionally found in clear stands. S. birrea ssp. caffra is known to be highly salt tolerant: in Israel it grows vigorously when irrigated with salty water.

Native range
Botswana, Democratic Republic of Congo, Eritrea, Ethiopia, Gambia, Kenya, Malawi, Mozambique, Namibia, Niger, Senegal, Somalia, South Africa, Sudan, Swaziland, Tanzania, Uganda, Zambia, Zimbabwe

Tree management

Truncheons 100-150 mm in diameter and 2 m long can be planted. One of the fastest growing trees in South Africa with a growth rate of up to 1.5 m/year. Coppicing is a suitable practice.

Orthodox seed storage behaviour, although viability is lost in 1 month in open storage. Seeds store well in air-dry storage at cool temperatures. There are approximately 400 seeds/kg.

S. birrea ssp. caffra occurs in wooded grassland, riverine woodland and bushland and frequently on or associated with hills. It prefers a warm, frost-free climate but is also found at high altitudes where temperatures may drop below freezing point for a very short period in winter. The tree is frost sensitive and moderately drought resistant. Occasionally found in clear stands. S. birrea ssp. caffra is known to be highly salt tolerant: in Israel it grows vigorously when irrigated with salty water.

The S. birrea ssp. caffra tree is a prolific seed bearer: between 0.2 and 1.5 t of fruit have been collected from a single tree in 1 season in the wild. Mature fruit drops when still green and ripens to a yellow colour on the ground; fallen fruit can then be harvested. Seeds should be soaked overnight before sowing. Propagation is by seedlings or cuttings; gregarious root suckering. Over 95% success has been achieved by grafting 5-10 cm of scion material cut from the tips of branches. It is essential that scion material be collected immediately dormancy breaks.

Poison:  There are claims that the fruit may be used as an insecticide as well as a germicide. Among the Zulu, the fruit is used as an acaricide.

  All parts of the fruit of S. birrea ssp. caffra are edible. The vitamin C content of the fruit is 54 mg/100 g, which is 2-3 times that of the orange. The seeds are high in fat (56-61%), protein (28-31%), citric acid (2.02 %), malic acids and sugar, phosphorus, magnesium, copper, zinc, thiamine and nicotinic acid. The pulp can be consumed raw or boiled into a thick, black consistency and used for sweetening porridge. The fruit is an excellent conserve and makes a delicious amber-coloured jelly. The flavour of S. birrea ssp. caffra has been described as pleasant, sour-sweet, guavalike and tart. The nuts, described as a delicacy, are commonly used to supplement the diet during winter or drought periods in countries such as Tanzania and Zambia, as the oil in the seed is rich in protein. Protein contents of 54-70% have been reported for de-fatted nuts. They are mixed with vegetables or meat or may be pounded and made into a cake before consumption.

The fruits are eaten by cattle and goats and a wide variety of game animals, including elephants, which often behave drunkenly when the fruits ferment in their stomachs. Although the leaves are said to be slightly poisonous, in times of drought when there is no grazing, livestock owners will lop branches off the tree to use the leaves as fodder.

Fibre:  A relatively good quality rope can be made from the inner bark. 

Timber:  Wood is light reddish-brown to whitish with no definite heartwood, soft and light (air-dry 560 kg/m³). As trees attain large diameters, the wood is preferred for mortars, pestles, bowls and various local crafts, saddles, furniture and heavy crates. In South Africa, commercial utilization of the wood was halted in 1962 when the tree was officially declared a protected species throughout the country. 

Shade or shelter:  S. birrea ssp. caffra can be used most successfully as a shade tree in the garden or park and to line streets.

Tannin or dyestuff:  Bark contains 20.5% tannin and some alkaloids.

Lipids:  The nuts yield an oil with a quality and fatty acid composition comparable to olive oil but with a stability that is 10 times greater. A non-drying oil that burns like a candle comprises 56% of the seed. The walnutlike stone contains up to 6% edible oil (1 t of fruit yields 60 l of oil), which is occasionally sold on the local market. The oil from the seeds has preservative properties and, if dried and stored in a cool place, meat treated with it is said to keep up to 1 year. Zulu women of South Africa use the extracted oil as a cosmetic.

Medicine:  Bark of S. birrea ssp. caffra is used to treat a variety of ailments, notably fever, boils and diarrhoea. Together with butter, it is applied as an ointment for headache and pains of the eyes. It is claimed that blood circulation is aided by a steam bath of extracts of S. birrea ssp. caffra mixed with extracts from other plants and roots. Steam from the bark is also used to treat eye disorders. Bark decoction, when mixed with other medicinal plants, treats various infections such as malaria, syphilis, leprosy, hydropsy, dysentery, hepatitis and rheumatism, and is a laxative. It is also used internally and externally as a prophylactic against gangrenous rectitis. Leaves, bark and roots are used externally (as a rub) for snakebite, and internally (as a beverage) for toothache. It has occasionally been used in veterinary medicine.

Gum or resin:  The gum that exudes from the tree is rich in tannin and is sometimes used in making ink by dissolving it in water and mixing in soot.

Cuttings and truncheons strike readily and S. birrea ssp. caffra can be used to make a live fence.

Alcohol:  A popular, fermented alcoholic beverage is prepared from the ripe fruit. The yeast occurring naturally in the fruit is normally used for spontaneous fermentation. This beverage, commonly known as marula beer, has approximately twice as much asco