Lost Crops of Africa Volume 2: Vegetables by the National Research Council, National Academies Press, 2006
This report is the second in a series of three evaluating underexploited African plant resources that could help broaden and secure Africa's food supply. The volume describes the characteristics of 18 little-known indigenous African vegetables (including tubers and legumes) that have potential as food- and cash-crops but are typically overlooked by scientists and policymakers and in the world at large. The book assesses the potential of each vegetable to help overcome malnutrition, boost food security, foster rural development, and create sustainable landcare in Africa. Each species is described in a separate chapter, based on information gathered from and verified by a pool of experts throughout the world. Volume I describes African grains and Volume III African fruits
Where to get it:
Direct from National Academies Press (also available as a free PDF download):
Before I begin I'd like to reiterate a point made at the beginning of my review of the first volume in this series on grains: http://www.permies.com/t/57007/books/Lost-Crops-Africa-Volume-Grains. This book examines, and this review explores, a number of species that could, in practical terms, be removed from their native habitat and introduced elsewhere. In some cases, that should not present a problem. In others it would, or at least might. I strongly implore readers not to attempt to circumvent phytosanitary, legal or ethical norms when attempting to source novel foods. They exist as an often inadequate means to reflect a care for the planet and its people, and ensure that “fair share” is not equated with biopiracy. This seems to be less a problem in the case of vegetables than with grains (which may hybridise with relatives in their new habitat) or fruits (which may be distributed by birds), but the legal and ethical concerns remain. Indeed, I refer the reader to the first few paragraphs of that review for points that bear emphasis but would constitute repetition in this one.
At root is the concern that Africa is not inherently poor, but that Africa has been robbed, and that many of my ancestors (and indeed contemporaries) have been responsible for that armed robbery. I have no desire to perpetuate those many injustices.
I read this book after my successful investigation of potential crops in Volume 1 on grains. As with the first volume, the crops discussed are not necessarily, or even far from, “lost” in the sense of being unknown in Africa, but have received less attention in terms of the potential as crops both within Africa and elsewhere than they might. As with Volume 1 also some, such as okra (Abelmoschus esculentus), Moringa (Moringa oleifera) (a personal favourite) and lablab (Lablab purpureus) (which I incorrectly thought to be an Indian species) are to some degree familiar, while others, such as Baobab (Adansonia digitata) and Locust Bean (Parkia biglobosa) are merely names and pictures, and a few such as Egusi (Citrullus lanatus) and Enset (Ensete ventricosum) (a long-lived perennial which produces starch by the cubic metre!) are entirely new to me.
Hopefully needless to say I'm keen to draw the attention of African readers to this book: the intention of this volume is first and foremost to provide Africa with a better future. Africa has contributed to (sometimes voluntarily, sometimes not) a homogenisation of global agriculture, but the continent and its farmers also have much to contribute to (and benefit from) a reversal of that process. African crops are now found in much of Asia, and Asian and South American species are found across much of Africa. Most of Africa's food crops come from elsewhere.
Indeed one of the greatest frustrations of this volume is that the authors note that around 3000 vegetable-type plants may have been consumed in various parts of Africa in the relatively recent past, while this book has been narrowed down to a bare couple of dozen, many already familiar. I'd certainly encourage African readers to identify domestic species not mentioned in this book that could be returned to the farm and the pot. Even those listed have immense potential to contribute towards nutrition, food security, rural prosperity, and general landcare within Africa and many have such potential outside the continent, provided issues of further exploitation can be overcome. This approach seems to present as promising a means of addressing malnutrition as does the “biofortification” of cereal grains whether by genetic modification or otherwise, while providing greater food security.
I'm keen to encourage African readers to employ the crops listed here for a range of purposes. Their employment elsewhere remains, again, a complicated subject. Many of these crops might well be of value outside Africa, for much the same reasons, and few are likely to present issues with an invasive potential. Assuming suitable germplasm can be obtained, the same issues apply to these plants as apply to many of the grains discussed in the first volume. I'd be broadly okay with crop-breeding operations that could result in new strains being returned to Africa, and with production on a subsistence scale, but have serious issues with commercial operations that could get in the way of African exports from farmers attempting to escape poverty. Agreements with the suppliers of seed and other germplasm seem vital. Some plants, such as amaranth (Amaranthus spp) and okra (Abelmoschus esculentus), are already being grown elsewhere: commercial cultivation of dika (Irvingia gabonensis) (which shows promise as an undercrop in tree habitats) and egusi (Citrullus lanatus) outside Africa present global justice issues, while others, such as shea (Vitellaria paradoxa), seem unlikely to do well outside Africa.
As with the other volumes in this series, this book discusses the uses, potential and propagation of a number of plants which have been widely ignored by organised (or even disorganised) breeding and other scientific efforts, with the aim of encouraging the use of these crops for food and other purposes, some economic. Each is examined for likely relevance to survival and social stability: nutrition, food security, rural prosperity, and general landcare. There is a detailed description of each plant, its known uses and its requirements for growth and propagation. Most are adapted to the tropics, but many have been found to do well into subtropical, warm temperate and Mediterranean regions. I want to concentrate, therefore, on plants which show most promise outside Africa while minimising impacts within Africa of cultivating them outside it.
I've eaten amaranth as callaloo, as it's known in the Caribbean, and highly recommend it. This is a plant with a great nutritional profile, which can be grown in many climates, but is poorly suited to export. It grows incredibly quickly, and is a great source of protein and essential vitamins. It's well known in some areas, and is already grown in homegardens, and grossly underutilised (often with a bad reputation) elsewhere. It is sensitive to temperature, and ideally needs a long growing season with plenty of water (I suspect it's not suited to Mediterranean conditions, for example). It uses the C4 photosynthetic pathway. Improved varieties should be returned to Africa in order to improve food security there. It's probably not much use to me unless my plans change drastically, but others from the tropics to warm temperate zones would almost certainly benefit from it.
The bambara bean (Vigna subterranea) may well be a viable alternative to the peanut, and readers in suitable (hot and dry) climates might want to consider growing it as part of a polyculture. That said, its export potential is high and shows particular promise for helping women farmers out of poverty. I would recommend against growing this plant commercially outside Africa. While it might otherwise do well in the Mediterranean, you do need to know that the plant appears to be sensitive to photoperiod: varieties from the far south of Africa might transplant to southern Europe, but even this might be out of its photoperiod range. It's down as a maybe. It may be a source of germplasm for hybridisation with other Vigna species, but some of these are already major crops (such as the black-eyed bean – long bean complex (Vigna unguiculata) discussed below, while others are wild species with which hybridisation might present problems.
The authors state that “Although the baobab grows satisfactorily outside Africa, it seems unlikely to become a significant vegetable resource in locations where it is not now employed in that manner.”
I'm not convinced. They also state that “In overall utility, perhaps no tree on earth surpasses baobab.” In Volume 3 (review forthcoming) they add
“Improving the plantings and productivity of baobab, to take a single example, would improve not just the rural landscape but also the social landscape, economic landscape, and even the topography of human health. Moreover, the improvement of baobab is a practical matter well within the capability of plant lovers, horticulturists, philanthropists, activists, educators, entrepreneurs and—most of all—innovative inhabitants of the lands where baobab trees thrive.”
Just how am I supposed to respond to a challenge like that? With careful propagation, I think Baobab (Adansonia digitata) should grow in Iberia, provided I can give it a frost-free microclimate. This may be one for my tallforest zone. The main problem seems to be that nothing else will grow under it, although whether this is due to massive nutrient competition or to alleleopathy is not clear. This may allow the creation of a firebreak zone.
I'm less excited about Celosia (Celosia argentea), which I know as an ornamental, not a food (had I known this before it might have headed off some grief with my square neighbours), but it's eaten as a green vegetable in many parts of the world. It has good potential in Africa, but export opportunities are limited, so I think this is one for the garden.
The cowpea or, as I know it, the black-eyed bean (Vigna unguiculata) is another of those plants not so much lost to those who eat it so much as under-investigated as a major food source. This plant has deep, nitrogen-fixing roots and grows well on poor soils, where the large leaves help prevent evaporation. I can't say I've exactly subsisted on these beans, but I have eaten my share, finding them tasty and versatile. They're already grown as part of polycultures. In Africa it is prone to attack by insect pests, both standing and when stored (growers in India add neem (Azadirachta indica) leaves to the storage bins, but neem is a known invasive outside India), but will probably do well as far as Mediterranean climates. It outcrosses readily with other Vigna species, which could be a problem, although many of these are in commercial production: mass outcrossing should allow the development of local landraces. This one has already escaped Africa, and its more general adoption seems to present few problems, although I'd be cautious of the prospects for uncontrolled hybridisation with wild relatives, which could be an opportunity in controlled conditions or a problem if they get loose.
The African form of what Americans know as eggplant (Solanum melongena) and I know by its French name of aubergine is also one that may bear greater cultivation outside Africa. The various related species have an interesting intertwined history, which I won't go into here. I know many people who love the familiar form of this plant and eat it in large quantities. Personally, I have no idea why anyone with such high culinary standards as the French should be blamed for what I consider a last-resort vegetable, with appalling texture and minimal nutritional value or flavour, surpassed only in times of utter desperation by the bitter gourd (Momordica charantia), but if you can grow the purple variety and enjoy it, then the paler egg-like African one would certainly bear cultivation.
Actually, this unfair. The eggplants of Africa are of several different species, of which this book concentrates on one, Solanum aethiopicum. They come in a multitude of colours, and some are even sweet and can be eaten as the fruit they are. The problem would be sourcing the right ones for your own preferences and climate. I might even consider that worth the effort, and the book does discuss important values for this plant, not least yields and its ability to grow in shade. It's fairer to say that this is a plant with unrealised potential.
Lablab (Lablab purpureus) is one of those beans with a clear place in many polycultures, and which deserves more attention within Africa, from where it spread to several other parts of the world. This is a deep-rooted, nitrogen-fixing plant that produces a protein-rich vegetable. I like lablab, but it's a premium airfreighted vegetable in Edinburgh, which I consider worth eating but not worth the extra cost and food kilometres. It's suited to cultivation well into Mediterranean zones, and will go on my planting list.
Marama bean (Tylosema esculentum) fascinates me. A plant of the Kalahari, it's evolved into a niche with limited and unpredictable rainfall (although it will “cope” with up to 800mm a year), extreme heat (>50C), and cold desert winters. It produces an edible bean with a protein content to rival that of the soya bean (Glycine max), yet thrives in its hellish native conditions through storing food in an edible tuber. It does best in sandy soils where little else will grow, and may be an ideal plant for some of our more degraded soils. It's a long-lived perennial (one tuber was found weighing more than a quarter of a metric tonne, although it was probably tough and inedible by that point) probably best grown as a biennial in a neglected plot. A self-incompatibility system encourages outcrossing, helping it to adapt to vile conditions, and may be one of the things we need for living in an increasingly disrupted climate. It has now been successfully grown in Greece, Israel, Australia, and Texas, California and Florida in the US. That one goes on my list as well.
Everyone who lives in a climate that will handle it is advised to grow Moringa (Moringa oleifera, although there are other species worthy of attention). I'm not going to go into detail. It's that good: I advise you to learn to grow it and then worry about what you're going to do with it later. It can be grown as an annual, so a sufficiently long and warm summer should do it.
I'm also not going to spend a lot of time on Africa's native potato varieties: this book covers two: Solenostemon rotundifolius and Plectranthus esculentus, both members of the mint family. They may be better adapted to conditions within Africa than the South American potato, and have found homes elsewhere, but I'm currently treating them as a curiosity for my own purposes. I may experiment with them if I can obtain germplasm, but seem to offer few advantages over the familiar potato (Solanum tuberosum), except perhaps as backup in case of disease affecting my common potatoes.
Okra (Abelmoschus esculentus) is a plant with more potential than I believed. Some varieties are perennial, although these do not seem to set seed in the temperate summer. It's open to use as a fibre crop, among other things. The plant itself is not one I overlooked, but I did ignore many of its valuable properties. Hybridisation with relatives might also be both interesting and constructive.
The yambean (Sphenostylis stenocarpa) is known to grow in Mediterranean regions, is a reliable and high-yielding nitrogen fixer, and is grown for both its protein-rich root (“the total protein yield per hectare for the tubers exceeds that of soybean”) and its nutritious beans. Like several of the plants in this book, the protein quality is high, often complementing other sources. In many ways it's probably superior to its American counterparts, the Mexican yambean (Pachyrhizus erosus) and the Amazon yambean (Pachyrhizus tuberosus), although the former has yielded up to 160 tonnes per hectare under ideal conditions. This is clearly a plant with much potential, especially in Africa, “with several of the field trials subjected to ‘unauthorized testing and sampling’ at night by local farmers!” I will probably attempt to source all three, perhaps engaging in hybridisation trials.
This book is a truncated version of part of a longer series that was planned, and a number of species were omitted from a shortlist of a much longer one provided by a number of interested parties. The shortlist can be found in an appendix to Volume 1, and this might be worth examining for other ideas.
In conclusion, this is handy book for readers seeking novel foodstuffs from the tropics into Mediterranean regions. I especially commend it to African readers, who I hope will use it as inspiration to explore more of the many hundreds of native vegetables known to some degree or another on this continent. It's been interesting for me to note that many such foods are barely known even where they grow wild (of which the same is true here, of course), and these may provide resilience against drought, famine and poverty.