Traditional Food Plants of Kenya (National Museum of Kenya, 1999, 288 p.)

Patrick M. Maundu

Grace W. Ngugi and Christine H.S. Kabuye

ILLUSTRATIONS BY LUISE GULL AND NICHOLAS S. MUEMA

Kenya Resource Centre for Indigenous Knowledge (KENRIK)

NATIONAL MUSEUMS OF KENYA

Published by Kenya Resource Centre for Indigenous Knowledge (KENRIK)
National Museums of Kenya
P.O. Box 40658
Nairobi, Kenya

© 1999 National Museums of Kenya

ITK: All rights reserved

Be advised that the indigenous traditional knowledge contained in this volume has been given in good faith as a contribution to the common good and the furtherance of mutual understanding and the preservation of all life on our planet and not to be used for personal or commercial gain and must be treated with respect and used only for the purpose for which it was gifted. Anyone who reads this volume assumes the moral and ethical obligations implied by this statement.

Editing: Caroline Agola, P.O. Box 21582, Nairobi

Design, layout and typesetting: Graeme Backhurst, P.O. Box 15194, Nairobi

Cover photographs (clockwise from top left): Vangueria infausta, Acokanthera oppositifolia, Uvaria scheffleri, Citrullus lanatus, Nymphaea nouchali, Thylachium thomasii

Photographs: All by Patrick Maundu except Hyphaene compressa, plate 3, which is by David Lowe

Cataloguing-in-publication data
Traditional food plants of Kenya/Patrick M. Maundu, Grace W. Ngugi and Christine H.S. Kabuye-
Nairobi, Kenya: National Museums of Kenya, 1999
Index
Bibliography: p.

ISBN 9966-9861-4-6

This publication may be reproduced in whole or in part, and in any form, for educational or non-profit purposes without special permission of the copyright holder provided due acknowledgement of the source is made.

Reproduction for sale or other commercial purposes is prohibited without prior written permission from the copyright holder.

Additional copies of this book are available from:

The Library
National Museums of Kenya
Museum Hill
P.O. Box 40658
Nairobi, Kenya

Printed by: English Press Limited, Enterprise Road, P.O. Box 30127, Nairobi, Kenya

Foreword

This book is a result of four years' research on indigenous food plants of Kenya. The original data was obtained from the plant collections in the East African Herbarium at the National Museums of Kenya (NMK) and was expanded through extensive ethnobotanical fieldwork carried out during the Indigenous Food Plants Programme (IFPP), 1989-1992.

The programme was implemented by the National Museums of Kenya in collaboration with the Kenya Freedom From Hunger Council (KFFHC) and Worldview International Foundation (WIF) (Kenya), covering Kajiado, Baringo, Turkana, Siaya, Nyandarua and Kilifi Districts.

During the final year, the programme also covered Machakos, Kitui, Mwingi and Makueni Districts, through a contract with World Neighbors.

The IFPP set up an Indigenous Food Plants Database, now at KENRIK in the NMK, which has data on over 800 indigenous plant species used for food in one way or another. Of these, fruits form about 50%, leafy vegetable 25%, tubers and roots 12.5%, gums, resins, spices, herbs and those used for tea, and other minor food products making up the rest. However, this book deals with 175 species, which are of particular importance, especially among the communities the programme worked with. The book also covers in less details about 130 other closely related species traditionally used for food in Kenya or elsewhere. Some of these species are little known because of their localized use or distribution but still have the potential to be used more widely. Many are collected from the wild, a few are in transition to domestication, while even fewer are well-established crops.

The book aims at helping the user appreciate the wealth of food-plant resources traditionally used in Kenya and how to recognize and utilize them for the well-being of society at large and particularly the local communities who are the custodians of the resources and information presented. Besides food use, other uses are mentioned. Of particular interest are medicinal uses where the distinction from food uses may sometimes be unclear, especially among pastoral communities who rely heavily on wild species. Ethnoveterinary, cultural, household and a host of other uses are also listed in an attempt to show the value of each species to the communities concerned, as well as its potential for use elsewhere. A salient characteristic of foods obtained from indigenous plants is their relatively high nutritional value, an important point for nutritionists in extension work.

Although this book deals with both naturally occurring and cultivated species, the emphasis is on the relatively less known but locally important species that are indigenous to Kenya. The book also includes a few cosmopolitan exotic species of cultural and nutritional importance, such as some Amaranthus species, and a few traditional food plants whose specific origins are still debatable - Solanum nigrum being a good example.

Information on the status of the species and their distribution will be useful not only in decision making but also in efforts to encourage the sustainable use of food and other plant resources. The awareness created by this book will lead to increased use, more respect and appreciation for these valuable foods as well as conservation of the species, their various forms and the preservation of the associated indigenous knowledge.

The book will be useful to researchers, social and development workers, those working in conservation and others interested in the subjects covered. It is my hope that it will also contribute to development, conservation of cultures and the associated plant resources.

Mohamed Isahakia
Director-General, National Museums of Kenya

Acknowledgements

The production of any ethnobiological work involves an enormous number of people. A few of those involved in the production of this book are mentioned here, but all those who are not should feel that their role was also important and is appreciated.

Work of the Indigenous Food Plants Programme (IFPP) which led to this book would not have been possible without the generous grant from the Ford Foundation for which we are deeply grateful. In this connection special thanks go to Dianne Rocheleau and Eric Rusten, Program Officers at the Ford Foundation's Eastern and Southern Africa Office in Nairobi, for their great interest and encouragement throughout the IFPP period.

We are grateful to the Canadian Organization for Development through Education (CODE) for providing funds through their Eastern Africa Regional Office in Dar-es-Salaam for production education and extension materials. In this Scott Walter, and later Julie Holder, were very helpful. In addition, the programme received seed money from Nog Meer Binding Foundation and Columbine Foundation of the Netherlands.

We are grateful to Richard L. Leakey former Director and later Mohamed Isahakia Director National Museums of Kenya for their encouragement given to IFPP.

In nutritional research, we are indebted to S. Mbugua and J. Imungi of the Department of Food Science, University of Nairobi for their support and permission to use laboratory facilities for food-value analyses.

Of particular mention and appreciation is the contribution made by the management and staff of IFPP in implementing the programme: Moses Mbugua, Secretary General, Kenya Freedom From Hunger Council (KFFHC); Grace Kanyua, Director, Worldview International Foundation Kenya (WIF); Joe Kuhn who initiated the programme and worked tirelessly to get it off the ground; Matthijs de Vreede who assisted in the programme design and continued to provide advice; David Lowe and later Bernard Muchiri, Coordinators; Abbey Olendi, Nutritionist; Gatonye Gathura, Communications officer; Jane Makumi, Programme Secretary; Nicholas Maina, Driver; and the late Peter Olala, Gardener.

The success of IFPP depended highly on local leaders and committed field collaborators who took the programme as their own, and to the local communities contained in this book and to whom much of it belongs. We are deeply indebted to them all.

Kajiado: J. Kimani of Maasai Rural Training Centre (MRTC) and the staff of the Elang'ata Wuas Ecosystem Management Programme, especially Charles Samperu, Ezekiel Roimen, Irene Katete and David Moile.

Baringo and Koibatek: Justus Kumu of the Food Security Programme and Fr Sean McGovern of the Kositei Catholic Mission.

Turkana: Mr Karanja of the Ministry of Agriculture, Livestock Development and Marketing (MALD&M);Turkana, KEFRI staff, especially Rosina Auren; the staff of the former Turkana Cultural Heritage Project (TCHP) and especially Sammy Emekwi Nalukoowoi, John Rigano, Geoffrey Clarfield, Dominic Akeno, John Ekales, Pauline Lokuruka, and Christopher Eweikar of Kaputir Community Health Clinic.

Kilifi and Malindi: the staff of the Malindi NGO programme in Magarini Division. Special thanks go to Shida Kaplanga, Shadrack Magambo, Mary Ngonyo, Charles Nzai, Rachael Kafedha, Esther Gona, Samson Chengo and the late Edward Jeffwa for their commitment to the programme.

Nyandarua: the extension staff of the MAL&D and Olkalou Council. Special thanks go to Marion Kaniu, Kennedy, and Jane Mathenge.

Siaya: the staff of the Lake Victoria Programme I and II, and especially Justo Oremo.

Machakos, Makueni and Mwingi: Elkanah Odembo, Director, World Neighbors, and the staff of the World Neighbors Ukambani Programme, Arnold Maingi and F.S. Musembi.

Kitui: World Neighbors staff in Kitui, Alexander Mutiso and J. Syombua.

Some additional information which benefited the book was obtained in Kitui during the project on Indigenous Agricultural Knowledge Systems (INDAKS) implemented by Kenya Resource Centre for Indigenous Knowledge 1994 - 1997 and funded by the European Union through the Leiden Ethnosystems and Development Programme of Leiden University.

Final stages of the book and printing were made possible by funds provided by the International Plant Genetic Resources Institute (IPGRI), the Swedish International Development Co-operation Agency (SIDA) and the United Nations Educational, Scientific and Cultural Organisation (UNESCO); for this we are particularly grateful to Frank Attere, Dr Luigi Guarino and Henry Kamau (IPGRI), Christine Holding (RELMA, SIDA) and Robert Hoft (UNESCO) for their interest in seeing the book published. We are also most grateful for the invaluable contributions of Bo Tengnas, Caroline Agola, Graeme Backhurst and Christine Holding in editing, formatting and seeing the publication through the printers.

We are indebted to the following for checking the local names in their various languages with great care: Boran and Gabra: Hassan Gurancha Wario: Chonyi: Joshua Buni Mturi; Daasanach: Richard Rogono, Eric J. Ness, Haira Makoro, J. Yeragalech Komoi, Gosh Kuanyang; Embu: Esther Njiro; Giriama: Joshua Buni Mturi, Kikuyu: G.M. Mungai, S. Mathenge; Kisii: David Nyakundi; Luhya: P. Masinde, P. Namachanja, S. Simiyu, Pius Ndinyo, Dinah Khayota; Maasai: Joyce Nasieku, Charles Ole Saitabau; Luo: Alfred Odhiambo, the late Peter Olala, H. Omondi Odongo; Marakwet: J. Kasagam; Mbeere: Ephantus Mwangi Ndiritu: Meru: Faith Njeru, J. M. Ruthiiri, Rendille: John Rigano; Somali: Abdirahman I. Yusuf, Suleiman, Ibrahim Serar; Sanya: Komoro Badula, Baloni Badula, Bini Baloni, Safo Badula, Godana Badula; Taita: G. Mwachala, Teso: P. Ipulet; Turkana: Sammy Emekwi Nalukoowoi.

We are grateful to Abede Kifetew of Ethiopian Curio Centre in Nairobi for providing useful information on teff and coffee, Jacob Muhando for plotting species distribution on the maps, Pius Namachanja for preparing the agro-climatic zone map, and to Yasuyuki Morimoto, Geoffrey Kilili and Patrick Kobai for their input on the final layout. We are also grateful to Joshua Muasya who drew some last-minute illustrations.

Last but not least, our most sincere thanks go to Bettina Ng'weno, J. Nyokabi Oteba, Francis Sikuku, the late Joseph Musyoka Kavisa and Benedetta Nthenya who carefully entered the original work in WordPerfect and AskSam database, Jane M Macharia and Phyllis Karanja for carrying out corrections, Joyce Chege for entering data on late records and L. Sojah for painstakingly matching the local names in the index with those in the main text.

Introduction

Background

Botanical and ecological diversity in Kenya

Plants are essential for human existence. They are the direct source of the world's staple foodstuffs in the form of their seeds, fruits, leaves and tubers, for example, or as less important products such as edible gums. Other species provide products or services that people depend on directly or indirectly, e.g. medicine, fodder for livestock, fibre, materials for construction, shade-the list is a long one!

Ecologically, there is a great deal of variation within Kenya which has extremes of environments (see Map 3). Land rises from the coastal zone and the lowlands of the north and north-east-where day temperatures exceed 40°C - to the cool highlands and mountain tops in the centre of the country, including Mt Kenya with a summit at 5,199 m, which is permanently snow covered. This great altitudinal range significantly influences rainfall and temperatures in various areas of the country, which in turn dictate the dominant vegetation types. Precipitation ranges from 150 mm annually in the dry low-lying deserts of the north and north-east to over 2,500 mm on the slopes of Mt Kenya. Likewise, vegetation ranges from almost bare rock and sand dunes in the deserts through Acacia-Commiphora bushland to grassland with scattered trees, dry highland forests, tropical rain forests and to alpine vegetation. This wide ecological range has resulted in a rich flora of about 7,100 distinct plant species and several thousand subspecies and varieties. Some of these species have a wide, almost world-wide distribution (e.g. some weedy species such as Amaranthus spp.), while others, or their subspecies or varieties, may have a more limited distribution. Some, for example Bridelia taitensis, are only found within the country (that is, they are endemic to Kenya), and others occur in even more restricted areas; for example the yet-to-be-described Salacia sp. = ndendela, Thui Hill, has only been reported from a single hill that covers an area of less than 4 hectares.

Ethnic diversity

The population of Kenya is also characterized by high diversity. Kenya is a meeting point of three major groups of people: Bantu, Nilotic and Cushitic speakers, each with a diversity of ethnic groups (see Map 1 and Table 1). Altogether, there are over 55 distinct languages and several hundred dialects. Some of these ethnic groups, such as the Kikuyu and Luo, comprise many millions of people, but others, like the Suba and El Molo, are small and their languages are on the verge of extinction. These original inhabitants of Kenya were later joined by people from other continents, e.g. the Arabian peninsular, India and Europe, thus further diversifying the linguistic and cultural situation. With the passage of time, and through observation and trial and error, a wealth of knowledge and experience about the environment, its resources and how best to exploit them was accumulated-for example, knowledge about the uses of plants as food, medicine and as poisons. This deep-rooted indigenous knowledge is necessary for the survival and well-being of a community in its environment. The Mijikenda, for example, use over 80 local species of plants as leafy vegetables, while the Turkana exploit over 140 species of edible plants obtained from their arid environment.

Historical and cultural change

The last century has brought more change for the people of Kenya than perhaps any other before. Western culture and modern science and technology are encroaching on traditional practices and eroding local knowledge. Modern times have brought new food habits and even several new crops. The plants from which traditional foods were obtained are now suffering a double tragedy: genetic erosion and loss of traditional knowledge on how to grow and use them. Many traditional cultivars, which evolved with the cultures concerned as they were consciously selected to meet specific cultural roles, have disappeared within the lifespan of the present generation. In many areas, even outside towns and cities, diets are based on fewer and fewer plant species: one in particular-maize-is becoming an increasingly dominant and widespread staple to the detriment of the health of families and national food security. This, coupled with low incomes and a misguided preference for expensive exotic foods, has contributed significantly to poverty in the country. Traditional farming systems, which are associated with specific traditional crops, varieties and technologies, are being abandoned, also resulting in increasingly monotonous diets and the loss of food-plant resources and indigenous knowledge about them. Specialized habitats such as indigenous forests and wetlands are being destroyed, similarly endangering specific forms and varieties of plants and sometimes resulting in the loss of entire species.

The role of food from the wild

Food from the wide range of traditional food plants makes supplemental, seasonal and emergency contributions to household food supplies.

Supplements to the staple food add flavour, which enhances the appetite. Some foods increase the absorption of vitamins, e.g. gum arabic (from Acacia senegal), and may help maintain the normal intestinal flora.

Many traditional plant foods are characteristically energy rich and play a crucial nutritional role during hunger periods. They may be equally important during periods when people have less time for food preparation, such as during peak agricultural seasons, or in arid regions where seasonal food-supply fluctuations are particularly acute. Commelina spp., for example, are strategically available at the beginning of the rainy season before other species can be harvested.

Perhaps the most common use of food from the wild is as snacks. Traditionally, people ate fruit between meals while herding cattle or working in the fields. Snack foods are especially important for children since they need to eat more frequently than adults. In addition, these wild fruit may supply micronutrients that are very important for the healthy growth of children but may be deficient in the bulky cereal-based diet in the home. Grewia spp., for example, are a major nutritional resource for pastoralists in dry zones.

Leafy vegetables collected from the wild play an important role in traditional diets in rural areas. In some cultures such as the Luhya, Kisii, Luo and Mijikenda, traditional indigenous vegetables are a common food in the diet. While some may be collected from the wild, a sizeable number have now been cultivated, including Cleome gynandra, and Crotalaria, Solarium, and Amaranthus species.

Nutritional value of traditional food plants

If hunger periods lead to actual starvation, or if other calamities such as war cause emergencies, a range of food plants, although sometimes requiring complex preparation to avoid toxicity, can provide a life-saving buffer, as is the case with Balanites pedicellaris and Boscia coriacea among the Turkana of north-western Kenya.

Although malnutrition and famine did also occur in the past, the nutritional benefits that resulted from the consumption of a wide variety of plants in the olden days were undoubtedly great and have been lost in modern times. If these traditional food plants could be promoted through extension work, better nutrition and better health could be achieved (see Appendix 1).

Nutritional problems in Kenya

The main nutritional problems that occur currently in Kenya can be summarized as follows:

Low energy and protein intake

People do not eat enough food of all kinds. In many areas food shortages are seasonal, being most severe at the end of the dry season and at the beginning of the rains. In addition, eating habits are changing-tea, for example, is replacing the more nutritious millet porridge for breakfast among many communities, a habit that is particularly detrimental for children's nutrition.

A number of traditionally used wild plants are good sources of unsaturated fats which, even in small quantities, can play a vital role in increasing the energy content of staple foods while making them more palatable and less bulky for children to eat.

Lack of variety in the diet

A varied diet is likely to be a well-balanced one. More important, the use of different foods, even in small quantities (snack foods), improves the flavour of the staple food and thus tends to increase overall consumption of the staple. Dietary deficiencies and food insecurity are strongly related to the decreasing diversity of traditional diets.

Vitamins

Vitamins are essential for the body's metabolic processes to take place normally.

Lack of Vitamin A: Vitamin A deficiency can lead to dry-eye disease (xerophthalmia), night-blindness and eventually complete blindness. Children who are deficient in vitamin A are more likely than healthy children to die from infectious diseases. Yellow fruits and green vegetables, as well as dark green leaves, are good sources of this vitamin. Fats, protein and zinc help the body to absorb and use vitamin A, thus a diet low in these nutrients can contribute to vitamin A deficiency. Nuts and oil seeds, in addition to fruit and vegetables, help to meet this nutritional shortfall.

Low levels of riboflavin (Vitamin B): Riboflavin deficiency is responsible for eye and skin disorders. Many wild foods, especially leaves, are good sources of this vitamin, and wild leafy vegetables have sometimes been found to have significantly higher riboflavin levels than cultivated varieties.

Other vitamins: Several other vitamins are essential for a healthy body. Vitamin C (ascorbic acid) is readily obtainable from fruits and fresh vegetables. Fruits such as baobab (Adansonia digitata) and morula (Sclerocarya birrea) are exceptionally rich in the vitamin. Vitamin E is abundant in vegetables such as purslane (Portulaca oleracea).

Iron and iodine deficiency

Iron is essential for the manufacture of haemoglobin, the red pigment in the blood. Low levels of iron lead to anaemia which is a major health problem in many parts of eastern Africa, particularly for women. Many traditional foods, especially dark green leaves, are good sources of iron.

In some areas of Kenya, the soils are deficient in iodine and therefore the diet is also deficient in this mineral. Iodine deficiency causes goitre and mental retardation in children. This deficiency can be prevented by importation of foodstuffs grown in other areas where there is no iodine deficiency and by use of iodized salt.

Table 2. Marketed species

The species listed in Table 2 have either been seen in markets or arc reported to be sold either in the raw or processed form. Most of the species are marketed in specific areas and seasons. The buyers may also be a specific group of people.

* Exotic species

Notes:

1. Many important food plant species are normally protected in their wild state but only a few are widely cultivated.

2. This list excludes those species sold for medicinal and other purposes.

3. Nyanza, Western, Coast, Eastern, North Eastern, Nairobi, Rift Valley and Central refer to Kenyan administrative Provinces.

Economic considerations

Easy access

Many traditional food plants grow wild. Therefore, where they are accessible, they can be collected freely and are thus available to everyone, including the poor. But these traditional vegetables may also conveniently be grown within the homestead in kitchen or homegardens. This is a common practice among the Kisii, Luhya and Mijikenda.

Contributions to household economy

Other traditional food plants are commercial in the sense that they are collected and sold, and yet others are cultivated either for household use or for sale. Many species, especially leafy vegetables, contribute to income generation, and such sources are often important for women and children in poor rural areas (Table 2).

Plant domestication

All wild species treated in this book are occasionally consciously protected by the communities in areas where they occur and therefore are often spared when vegetation is being cleared. A few may also be managed in their natural habitat (e.g. by pruning), while in other species seeds, saplings, cuttings or other parts of the plant are collected for propagation in fields or homegardens. Selection of tree species for domestication or management is based on their overall usefulness (e.g. as a shade tree), availability of propagating material and convenience of growing it.

Table 3. Wild food plants rated highly for domestication

* = semi-domesticated: this group includes plants whose food resources are picked from the wild but which are also often planted on a small scale in cropland and near the homestead.

Considering the vast number of potentially edible plants that occur in the wild, many of them yet to be discovered, there is considerable scope for domestication and breeding of new crops (Table 3). Introduced crops often require reliable rainfall and large amounts of pesticides and fertilizers to perform well. Indigenous plants exist in a better balance with other components of the ecosystem, and can produce without expensive inputs.

Few of the plants described in this book are currently cultivated and little or no consideration has so far been given to their genetic improvement. Therefore the vast potential of the genetic resource represented by traditional food plants has barely begun to be exploited.

Cultivated species

Out of some 3,000 different plant species that have been commercialized (1% of the total number of plant species in the world) only 20 are consumed on a large scale. In fact, as much as 80% of world human energy intake comes from only 15 species of plants and animals. These 15 main foods are, however, not always the most nutritious. As already pointed out, this concentration on a few species has resulted in a vast number of potential food-plant species being neglected, genetic erosion and loss of associated indigenous knowledge.

The few crops that are now dominant were domesticated long ago, most in just a few regions in the world, e.g. the Middle East, the Ethiopian highlands, South East Asia and the highlands of South America (Table 4).

The promotion of traditional food plants

Traditional food plants, both domesticated and non-domesticated, have been neglected throughout the world. Kenya is no exception. Instead of concentrating on commercial food crops, extension efforts should now be aimed at maintaining, popularizing and improving the accessibility of a wide range of species as this can do much to improve nutrition and food security. A rich flora providing a variety of snack foods located near or in school compounds, for example, would improve the health of school children.

Even as individual citizens we have a responsibility to maintain the maximum possible diversity in our food plants and use them for everyone's well-being. To achieve this we need to:

· Make sure we and our families eat more traditional foods;

· Discard the false and unwarranted notion that traditional foods are inferior;

· Take the initiative to grow those species that we can grow ourselves and to manage others in the wild while preserving their habitats and ecosystems, even in our own back yards;

· Promote and keep alive indigenous knowledge about edible plants, methods of preparation, local names, etc., pass this knowledge on to our children and, where possible, document it;

· Identify rare and endangered cultivars or varieties and liaise with the National Gene Bank at the Kenya Agricultural Research Institute (KARI) for long-term conservation.

Notes on the use of this book

Distribution maps

The maps in the Species Accounts section indicate localities where specimens of each plant were collected and stored by the East African Herbarium at the National Museums of Kenya in Nairobi. But these maps should not be regarded as providing a complete picture of each species' distribution in Kenya as it may also occur in other areas not represented in the Herbarium collection. In the case of a crop species, the areas indicated are those where it is cultivated.

Information for future editions

The authors welcome comments, corrections and additions from readers. These contributions (to be sent to KENRIK, National Museums of Kenya, P.O. Box 40658, Nairobi) should be accompanied by details of localities and person(s) supplying the information, and will be acknowledged appropriately.

A note for genetic and information prospectors

The information and knowledge about the plants in this book, and the methods by which they are used traditionally, belong to the communities concerned. Any proposed commercialization of this intellectual property, and the associated genetic resources, should be initiated in good faith, with acknowledgement to and the full participation and knowledge of the relevant peoples.

Table 4. Commonly used cultivated food species and their origins

* = Indigenous to Kenya;
** = Introduced but now naturalized in parts of Kenya;
? = Origin uncertain or disputed

Local names

* = exotic