Agroforestry a textbook at last

Sistemas agroforestales. Principios y Aplicaciones en los Tros, by Florencia Montagni, Laurel Prevetti, and Lori Ann Thrupp. Organization for Tropical Studies (OTS) and Center for Tropical Agronomy Research and Education (CATIE), San JosCosta Rica, 1986, 818 pp., $20.00

Ancient peoples learned to exploit patterns established by plants and animals as they occurred across the natural landscape and over time. Many traditional human societies developed sophisticated cultivation systems which mimic the horizontal, vertical, and temporal distribution of their local plant and animal communities. These systems yielded food, fibre, and fuel from within the framework of a stable ecosystem, and often shaped societal patterns in return.

It is now clear that monocultural farm, forest, and livestock production methods are sustainable only under certain climatic, topographic, and edaphic conditions. Agroforestry is the rediscovery of ancient concepts of resource management. It is a landuse system in space or time which combines trees with the stable production of crops or livestock, and it is emerging as one powerful and promising technical solution to the problem of human needs versus ecosystem degradation.

Within the last decade agroforestry systems have been advanced primarily by researchers in developing nations, in response to Third World needs. The serious long-term problems of soil erosion and loss of biodiversity are, however, as insidious in temperate climates as in tropical ones, and the principles advanced in the book under review are eminently applicable to temperate regions.

Until now there has been no generally available textbook on the subject. This book is the first basic text and a solid cornerstone of information. It is about long-term solutions, and it will endure. The first six chapters form a pragmatic guide to design and implementation of agroforestry systems. They include an overview, planning, site characterization, systems design, management, evaluation, and strategies for diffusing agroforestry concepts. The seventh and last, chapter is a research-oriented "Perspectivas de los sistemas agroforestales". But these seven chapters make up less than a third of the book. The appendixes are an overwhelming collection of invaluable information. Five detailed case studies are followed by sections of exercises, an instructor's guide, and 15 articles by the world's leading experts on the subject. The last three appendixes form an extensive annotated bibliography, 123 sources of information worldwide, a country-by-country review of institutions involved in agroforestry work, a world guide to sources of seed and genetic material, and sources of audiovisual and periodical media. The last appendix includes a 27-page index of plant species used in inventoried agroforestry systems in Latin America, and a 48-page catalogue of existing agroforestry systems in Latin America. Needless to say, this appendix is a compilation of an enormous amount of information, and completes the list of what this book is: text, teaching manual, and reference.

A massive work. This is not to say that the book is perfect. It is a first work, and a massive one at that. The senior author solicits suggestions for improvements to future editions. The weakest part of the book is undoubtedly chapter 3, "Planeamiento de sistemas agroforestales", and I suspect that this deficit reflects the state of the applied art. Part of the problem may also be inherent in a technical manual which must cover potential applications of unspecified scale. Although differing scales are indicated (regional, farm, field, species component) in a table with items to be considered in planning, the treatment lacks depth. The need for information to be used in assessment of environmental factors for project planning is given lip service in the name of potential fiscal constraints. While finances may constitute realistic limits for projects, the lack of an adequate planning strategy, based upon ecological principles, is a serious limitation to the comprehensive nature of this book. A reader might ask if this lack does not mimic the age-old problem which agroforestry concepts have the potential to solve: immediate need (money) versus environmental degradation. This deficiency points out that there is still work to be done. The authors have taken a gigantic first step, and their book is an unquestionable must for anyone interested in agroforestry.

Michael Jennings