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THE MONGONGO/MANKETTI NUT
rautanenii (Schinziophyton rautanenii)
!Kung Bushmen - //xa, mongongo
Lozi - mungongo
Shona - mungongoma
Tswana - mongongo, mugonga
Herero - mangetti, mongongo
Kwangali - ugongo (ngongo)
Africaans - wilde okkerneut
English - manketti nut, mongongo nut, featherweight tree (the wood
is very light)
the tree and fruit
Ricinodendron rautaneii is a large (up to 15 metres) straight
trunked tree, with a broad spreading crown with dark green compound leaves
of 5 to 7 ovate to elliptical leaflets at the end of a stalk up to 15cm
(6 inches) long, not unlike those of Casimiroa edulis. The branches
are stubby and contorted. There are separate male and female trees,
so solitary specimens will not fruit. In addition, trees take around 25
years to commence fruiting. The tree flowers - depending on local climatic
variations - in Southern Africa's hot dry season, which is around October
to December. The small whitish-yellow flowers become a somewhat oval, vaguely
plum-like fruit about 3.5 cm long and 2.5 cm wide. The young fruit is at
first covered in fine small hairs on its thin but tough outer skin; under
the skin is a narrow spongy layer, at first green, then turning whitish
brown with maturity. The fruit fall from the tree with the skin still green
(variably, april to may), and matures on the ground. There, the skin turns
brown, and the flesh softens and develops full flavor. This soft spongy
pulp layer is about 20% of the fresh fruit (by volume), pleasantly aromatic
and sweet at maturity. Its taste has been compared to a date, and although
high in sugars there is not an absolutely high amount:; there is (very
approximately) 1 gram of sucrose in the dried flesh of each manketti
Like many trees of seasonally arid or cold climates, the trees lose
their leaves every year, towards the end of the cold-dry season of autumn
and winter (variably, about June to the end of August). And it is at this
time that the last of the ripe fruit fall. They are a lot easier to see
when the leaves fall at this time, and it is easy to pick up the fallen
fruit. The supply of fruit decreases after winter, as the rainy season
(very variably, at some time in the period November to April, broadly regarded
as the 'summer rainfall' area) comes on; insect and animals destroy the
fruit where they fall. Even the dried, crumbly flesh of old fruit is edible
-there may be edible dried fruit on the ground for as long as eight months,
overlapping the fall of the new crop. Some bushmen remove the flesh from
the fresh fruit, dry it in the sun, and store it for use later in the year.
Both Bantu and Bushman peoples use the fruits, with the modern preference
being to boil the whole fruit to remove the tough and indigestible outer
skin, and make a sweet, maroon colored porridge - very similar to 'applesauce'(USA)/stewed
apples (British colonial) - from the flesh.
But the sugar content is only part of the story.
The big value is in the seed. The skin takes up 10% of the fruit by
volume, the flesh 20%. The remaining 70% is the nut-like seed, including
the wide hard shell around it. The 'shell' (endocarp) around the 'kernel'
is very thick indeed, and although porous, it is very hard and tough. So
hard that even elephants, which love the sweet fruit, can't crack them.
"A forester in Rhodesia [Zimbabwe] set this author some Manketti
nuts and on the package under the scientific name Ricinodendron,
he had written "recovered from elephant dung". This startled me. The nuts
are like oversized pecans which have had smallpox and were covered with
pockmarks. I wrote the forester to ask why the special inscription, and
he replied that there are three reasons: (1) The elephants eat the fruits
greedily and it is much easier to let the elephants do the job of picking;
(2) The seed will not germinate until it has spent a week inside the elephant,
and (3) The elephant enjoys the fruit but his digestive mechanism does
not affect the extremely hard shell and the nut inside. The natives of
Rhodesia, therefore, follow the elephant, recover the hardshelled nuts
where they have been dropped, clean and dry them, then crack the extremely
hard shell, and find the contents perfectly delicious."
Elephants, Loxodonta africana, are not the only animals to feast
on the sweet fruits. The greater Kudu, Tragelaphus strepsiceros,
produces the 'nuts' cleaned of the fruit as well, but from the other end;
it regurgitates the nuts some time after eating the fallen fruit, leaving
them in neat piles, ready for collection.
Edwin A. Menninger, 'Edible Nuts of the World'.
The Nut Meat
Once collected, the hard shell can be broken between two rocks, and
the single kernel (sometimes there are two) extracted. It is easier to
crack if it is roasted in a fire first - or, as in some areas, covered
in sand and a fire built on top. The kernel or 'nut meat' is surrounded
by a hard but thin seed coat which is easy to remove by hand. The kernel
is about the size of a hazelnut (the weight of Botswana and South West
African kernels is about 1.4 grams).
The creamy yellow nut meat is oily and nutritious; it is very good
eaten raw, and even more delicious when it is roasted. Indigeous people
sometimes mix the nut meat with sand and red hot ashes from the fire, after
which the roasted seeds taste like roasted cashews. Curiously, it is reported
that roasted for longer, they then taste like 'fine old cheese'.
of the kernel
Their nutritional content is outstanding. The kernel is 57% by weight
fat. Of this, about 43% are polyunsaturated fats (almost entirely linoleic
acid), about 17% saturated fats (palmitic and stearic), and about 18% monounsaturated
(oleic). Add the sugars in the fleshy part, and, by one estimate, an adult
man would meet 71% of his daily energy requirement by eating 100 fruits
(kernels and flesh). Indigenous people have been reported as eating around
100-300 fruit a day in parts of Namibia.
The kernel has 26 grams of protein per 100grams, an amount similar
to peanuts and other protein rich legumes.
The kernel has, per 100 grams, approximately 193 mg of calcium, 527
mg magnesium, 3.7 mg iron, 2.8 mg copper, 4 mg zinc, 0.3 mg thiamine, 0.2
mg riboflavin, 0.3 mg nicotinic acid, no vitamin C (the flesh has about
15 mg), and a stunning 565mg of vitamin e (almost entirely as y-tocopherol).
Due to the very high y-tocopherol content, the oil is very stable,
and doesn't oxidise into 'rancidity' for a very long time, in spite of
the African heat.
That these are a productive tree in their environment is undisputed:
one estimate is that each female tree has around 950 fruit a year, given
a sufficient rainy season. In a good year, they may be "knee deep" under
the trees, with yeild depending in part on how good the rains of the previous
year were. In areas where they are the dominant species they can occur
every 20 metres or so; some large stands have been estimated at up to 60,000
hectares. In the early 1900's, around 2,000 tons of nuts a year was exported
from Namibias dryland Tsumeb forests; presumably with little consideration
they were comandeering the local peoples most important food source in
an unforgiving environment.
The Manketti is a tree of seasonal drylands, surviving unreliable rains,
temperatures ranging from maybe 14º F in winter to well over 100º
F in summer. In its native Southern Africa it grows in suitable environments
in a rough band from the Northern Namibia/Southern Angola, past the Etosha
pan, the Tsumeb region, through Namibias' Caprivi strip area, the Okavango
of Botswana and Southern Zambia, across to Northern Zimbawe, the uplands
of Central Mozambique and Transvaal in South Africa. In it's 'core' area,
virtually coast to coast in the middle part of Southern Africa ( about
latitudes 15-21 degrees) on suitable soils it usually occurs in large groves
or more extensive stands, and is either the dominant tree in the stand,
or co-dominant.. Some groves are as much as several hundred metres wide,
and may run for several kilometres.
It's core area is mainly in more upland areas, generally above 1200
metres, although it is found down to 200 metres. It is a rather 'plastic'
species, in that the rainfall varies over the various regions of its range
can be from 400mm to 1,000mm. As mentioned, it suvives light frost through
to extreme daily highs.
It may be associated with alluvial soils near rivers, but most commonly
with stablised dunes and raised sandy plains of the deep kalahari sands.
It cannot tolerate areas subject to flooding. Generally it is found in
mixed open woodlands, and, as mentioned, sometimes as dominant stands of
Outside it's core area it appears only sporadically, or as a small
Where it occurs in mixed woodland, one region in Southern Africa has
found it associated with Afzelia quanzensis, Baikiaea plurijuga,
Burkea africana, Combretum spp., Guibourtia coleosperma,
Pterocarpus angolensis, Strychnos coculoides, and
Terminalia sericea .
It is used as a street tree in Victoria Falls, where the Zambesi river
falls off the arid southern Zambian plains at North western Zimbabwe.
Ditribution to other
There is little information on what attempts have been made to introduce
this extraordinary nut to other areas of the world with suitable climates
and soil conditions.
Seed was introduced to Australia in the late 1980's; some of the drier
areas, so long as they are not salinated, may suit it well.
However, I have seen no reports on whether or not the plants survived.
Israeli researcher Dr. Yosef Mizrahi introduced the tree to several
desert sites. So far, some trees could not tolerate the salinised soils.
The best growth has been in Besor, a cooler climatic region. The plants
became dormant in winter (in December) at this site, and did not break
dormancy until quite late - in June. Active growth continued for the next
five months, until November.
7 degrees Celscius below freezing was enough to kill young plants.
This will limit the number of sites it can be tried at.
Dr. Mizrahi found germination could generally be started by removing
the hard exocarp and treating the seeds with either ethylene or ethephon.
Germination is erratic, and takes place over an extended period. The seedlings
develop very deep roots very quickly - an adaptation to desert conditions
- and need appropriate nursery practices to accomodate this fact.
Another report says seeds planted in a glasshouse germinated within
one or two weeks when the hard outer exocarp was removed.
heudelotii ssp.africanum is a fairly common species in rainforests
of West tropical Africa from Guinea down to Angola, and as far east as
Uganda. It has been recorded in Wamba forest, Congo Democratic Republic
(formerly Zaire), more or less right on the equator, as well as in the
Mahale Mountains on the shores of Lake Tanganyika in Tanzania, just below
the equator, but only at higher altitudes - more than 1,600 metres above
sea level. It is a quick to establish, fast growing, straight boled
tree that is usually around 100 feet high, although sometimes it is much
smaller. This species seems to be a relatively early and fairly successful
colonizer of grasslands, in areas where farming has been abandoned. It
is therefore most widespread in secondary forest, rather than mature primary
There are seperate male and female trees, and trees in drier, more
marginal areas can defoliate and re-grow leaves when moisture returns.
Each fruit contains between two and three kernels. This species has a very
similar nut to the Mongongo, except that the kernel is a smoother and plumper,
and the seed coat is a little thicker. It is said to be as good eating
as the Mongongo nut. It is wild harvested and regularly traded in markets
in Cameroon, and is one of the major food sources of the Mbuti people,
of the Ituri forest in Zaire.
Arnold, T. H, Wells M. J., and Wehmeyer A.
S.1985. 'Khoisan food plants: Taxa with potential for future economic
exploitation' in 'Plants for arid Lands'.
Royal Botanic Gardens, Kew.
Bainbridge W.R. 1965: 'Distribution of
seed in elephant dung (Acacia, Ricinodendron, Hyphaene)'
Puku 3: 173-175
Biesele M., Bosquet J., Stanford G.1979:
'A Kalahari food Staple: Ricinodendron rautanenii'.
Pages 341-355 in: Goodin J.R. and Northington D.K (ed). 'Arid land
International Center for Arid and Semi-Arid Land
Studies, Texas Tech Univ. Lubbock.
Botanical Research Institute, Pretoria
'The Nutrient Composition of Manketti Fruit'
Botanical Research Institute, Pretoria. As reported in the Rare
Fruit Council of Australia Newsletter, May 1988
Botelle A.1999: 'Estimating Manketti
Nut Yields in the forest of Western Kavango, Namibia'
CRIAA SA-DC, Windhoek.
Büschel D. 1999: 'A Study of
Resource Utilisation: A case from Namibia, Mpungu Constituency, Kavango
District, Northern Namibia'.
CRIAA SA-DC Report, Windhoek, Namibia.
Chakanga M, Korhonen K. and Selänniemi
T. 1998: 'Forest Inventory for Caprivi Region'.
NFFP, Directorate of Forestry, Windhoek.
Fox, F.W. & Norwood Young, M.E. 'Food from the Veldt'
Delta Books, Johannesburg. 1982. ISBN 0 908387 32 6. Pages 193:195.
Chimbelu E.G. 1983. 'The availability,
use and Management potentials of Mungongo (Ricinodendron rautanenii,
Schinz): A Case study of the Southern Shungu Region, Zambia.'.
Ph.D. Thesis, State University of New York.
Chimbelu, E.G. 1988: 'Developing Zambian
tree resources through community needs and values.' In: Lungwangwa, G.
& Sinyangwe, I. (eds.) 'Utilizing Local Resources for Development:
Proceedings of the 9th PWPA Conference, Eastern, Central and Southern Region,'
held at Musungwa Lodge, Zambia, July, 1988. 1990. pp. 66-75, Zambia
Coates Palgrave K. 1983. 'Trees of Southern
Struik Publishers, Cape Town.
Du Plessies P. 1999: 'Report on the Manketti
Stakeholder Workshop held on 9th July, 1999'.
CRIAA SA-DC, NTFP 1, Windhoek
Dyer R.A.1975: 'The Genera of Southern
African Flowering Plants'.
Department of Agricultural Technical Services,
Pretoria; ISBN 0 621 02854 1
Erkkilä A and Siiskonen H. 1992: 'Forestry
in Namibia 1850-1990'.
Silva Carelica 20 244p.
Geldenhuys C.J. 1977: 'The Effect of Different
Regimes of Annual Burning on Two Woodland Communities in Kavango'. South
African Journal of Forestry, 103: pp32-42
Helgren D.M. 1982: 'Edaphic Context
of the Mongongo (Ricinodendron rautanenii) in the Northwestern Kalahari'
South African Journal of Science Vol.
Idani, G., Kuroda, S., Kano, T., & Asato, R. 1994. 'Flora
and vegetation of Wamba Forest, Central Zaire with reference to bonobo
(Pan paniscus) foods.'
TROPICS 3 (3/4): pages 309-332, 1994.
Keegan A.B. 1982: 'Dormancy and Germination
of the Manketti Nut, Ricinodendron rautanenii'. Ph.D. Thesis, University
of Natal, Pietermaritzburg.
Keegan A.B., Kelly K.M. and van Staden J.
1989: 'Ethylene Involvement in Dormancy Release of Ricinodendron
Annals of Botany 63, 229-234
Kumar V 1978: 'Studies of Mungongo Seed
TIRC/NCSR Research Paper No. 9, Tree Improvement
Research Center, National Council for Scientific Research, Kitwe, Zambia
Lee, R.B. 1973. 'Mongongo: The ethnography of a major wild food
resource'. In 'Ecology of food and nutrition' Vol. 2
Gordon & Breach, N.Ireland. 1973. Pages 307-321.
Mateke, S., McGonigle T. P. and Sinclair R.
C.1999: 'Mycorrhizal Contribution to the Establishment of Fruit Trees
in Southern Africa' eds. J. F. Devlin and T. Zettel. In: “Ecoagriculture:
Initiatives in Eastern and Southern Africa”. pp 131-148.
Muller, Hans 1988 'A trip to Africa' a personal report on African
fruit and nuts in Rare Fruit Council of Australia Newsletter, May
Mwamba C.K.1996. 'Status report on domestication
and commercialization of non-timber forest products in agroforestry systems'.
Tree Improvement Research Centre, National Council for Scientific Research,
Palmer, E & Pitman, N. 'The Trees of Southern Africa' Volume
Balkema, Cape Town. 1972.
Peters C.R.1987: 'Ricinodendron
rautanenii (Euphorbiaceae): Zambezian Wild Food Plant for All Seasons'
Economic Botany 41 (4)
Stanford G 1979: 'Preliminary findings
on germination of Mongongo seeds'.
Plant Propagation. Vol 25 (2): 2-4
Sih A. and Milton K. 1985. 'Optimal diet theory: should
the !Kung eat mongongos?'
American anthropologist. Vol. 87. Pages 395-401.
Swart W.J. 1990. 'Good Living – The Bushman
Trees in South Africa, Oct. 1990-Mar. 1991,
Taylor F.W. and Kwerepe B.1995. 'Towards
the domestication of some indigenous fruit trees in Botswana', in Maghembe
JA. Ntupanyama Y. and Chirwa P.W. eds. 'Improvement of indigenous fruit
trees of the miombo woodlands of southern Africa'; ICRAF, Nairobi
Timberlake J.R. and Calvert G.M.1993. 'Preliminary
Root Atlas for Zimbabwe and Zambia'.
The Zimbabwe Bulletin of Forestry Research No.
10, Zimbabwe Forestry Commission, ISBN 0-7974-1264-6.
Vahrmeijer, J 1976. 'Ricinodendron rautanenii Schinz,
Southern African Plants No. 4463,000-0010, 1976.
White, F . 'Forest flora of Northern Rhodesia'
Oxford University Press, Oxford 1962.
Mizrahi, Yosef in 'Fruit and Nut Trees--Appraising the
Treasure of the Desert'
Ag-Sieve, Volume II, Number 8, 1989
On - line published by Rodale International
[accessed October 1999]
Graz, F P. 2000. 'Schinziophyton rautanenii'
Polytechnic of Namibia
Department of Agriculture
[accessed February 2001]
-Note: the above reference is a 'key world information resource' for
this species, in my view.
A natural nut very high in Vit E
Small and Large quantities
available, we can ship worldwide.
Contact: David Siloka
SDK ESSENTIAL OILS, ZAMBIA
Phone 260 97 855088
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