Polyculture Production Principles, Benefits and Risks of Multiple Cropping Land Management Systems for Australia A report for the Rural Industries Research and Development Corporation by Larry Geno and Dr Barbara Geno May 2001 RIRDC Publication No 01/34 RIRDC Project No AGC-3A © 2001 Rural Industries Research and Development Corporation. All rights reserved. ISBN 0 642 58256 4 ISSN 1440-6845 Polyculture Production - Principles, Benefits and Risks of Multiple Cropping Land Management Systems for Australia Publication No. 01/34 Project No. AGC-3A The views expressed and the conclusions reached in this publication are those of the authors and not necessarily those of persons consulted. RIRDC shall not be responsible in any way whatsoever to any person who relies in whole or in part on the contents of this report. This publication is copyright. However, RIRDC encourages wide dissemination of its research, providing the Corporation is clearly acknowledged. For any other enquiries concerning reproduction, contact the Publications Manager on phone 02 6272 3186. Researcher Contact Details Agroecology Associates Bretons Road CROHAMHURST QLD 4519 RIRDC Contact Details Rural Industries Research and Development Corporation Level 1, AMA House 42 Macquarie Street BARTON ACT 2600 PO Box 4776 KINGSTON ACT 2604 Phone: 02 6272 4539 Fax: 02 6272 5877 Email: [email protected]. Website:http://www.rirdc.gov.au Published in May 2001 Printed on environmentally friendly paper by Canprint ii Foreword This comprehensive report provides a well-balanced synthesis of information available on what is termed polycultural production. Polyculture places an ecological framework to the growing of more than one crop at a time in one place. This report further: • Provides an innovative synthesis of worldwide information not previously available on polyculture production: including multiple cropping, permaculture, agroforestry and intercropping dimensions applicable to agriculture, forestry and aquaculture management. • Presents a strategy for sustainable land use intensification drawn from both traditional and modern practices. Polyculture is shown to offer the proverbial ‘free lunch’ by producing more from less. This technique is useful as questionable inputs are withdrawn from production under triple bottom line accountability. • Establishes polyculture as an exemplary integrating theme for understanding both native and manipulated ecosystems and their interaction. • Explores the science behind the benefits of polyculture, traces the conceptual development through time of the ecological theories of competition, complementarity, resource capture and plant interaction to show the transition from a static, structural understanding to a more dynamic, functional understanding of what is, at times the chaotic, nature of polyculture performance. • Establishes a firm scientific basis for polyculture production management. • Details desirable polyculture component characteristics and design principles for use in designing new farming systems, especially amenable to low input, organic and marginal land farming and for reducing environmental impact and enhancing ecological integrity. • Illuminates potential barriers and constraints to wider adoption and implementation of polyculture production as being biophysical, mechanical, social, economic and institutional. The report notes present low adoption rates and the need for future research, development, communication and adoption of polyculture principles and practices. This project was funded from RIRDC Core Funds which are provided by the Federal Government. This report, a new addition to RIRDC’s diverse range of over 600 research publications, forms part of our Organic Produce R&D program, which aims to optimise the profitability of Australian organic production in domestic and overseas markets and to promote the utilisation of organic farming systems as a means of enchancing the sustainability of Australian agricultural systems. Most of our publications are available for viewing, downloading or purchasing online through our website: • downloads at www.rirdc.gov.au/reports/Index.htm • purchases at www.rirdc.gov.au/eshop Peter Core Managing Director Rural Industries Research and Development Corporation iii Acknowledgments This research is dedicated to Bill Mollison, who has long grappled with the concepts of polyculture and their holistic application under his wider concept of permaculture. The Origins of Permaculture In November 1959, watching marsupial browsers in the floristically simple rainforests of Tasmania, I wrote in my diary: ‘I believe that we could build systems that would function as well as this one does.’ A casual reflection, not further developed, had broken the barrier between passive observation (in an attempt to understand inter-relationships between browsers and plants) and the active creation of many similar systems that we could construct ourselves. The step from passive analysis to active management, or active creation, was critical. I was also discovering over this period (1959-1962) that even two of these common browsers and no more than 26 woody plants species could set up a series of very complex interactions. Thus, it was the interactions of components, rather than the number of species that gave the system its flexibility. That flexibility allowed a fairly stable condition to be established through a variation in other influences, in weather and growth. The system constantly changed, but continued to function. This, then, was both the precursor and the core of Permaculture: the realisation that we can create systems, based on analogies of natural systems, or try to improve them for productivity, and then allow the created system to demonstrate evolutions, stepping in at critical stages to manage, or add or subtract species, and observing at all times. These system analogies, if well constructed and recorded, could produce a yield that could be constantly assessed or improved and would also need minimal maintenance energy after the establishment phase. (Mollison 1996) About the authors As researchers and commercial farmers for 25 years, Barbara and Larry have always sought ecological answers to the expectations of the land. Trained through PhD level in ecology and management, they have established polyculture farms in three countries, operated a national organic farm certification scheme, contributed to new crop development, grower organisations, popular and journal publications, and the advance of the concept of sustainability. Through their consulting, they endeavour to place solid, useful information in the hands of those who are on the land to develop successful models of adaptive human ecology. Barbara currently lectures at university, while Larry grows native fruit trees and consults on sustainable farm design. Barbara also is involved with the efforts of both the Centre for Australian Regional Economic Development (CARED) and the Institute of Sustainable Regional Development (ISRD) to promote sustainable solutions to regional development problems. iv Contents FOREWORD .......................................................................................................................III ACKNOWLEDGMENTS........................................................................................................... IV LIST OF TABLES AND FIGURES .......................................................................................... VII EXECUTIVE SUMMARY ........................................................................................................ VIII 1. INTRODUCTION.............................................................................................................1 1.1 Background to the Study ...........................................................................................1 1.2 Justification of the Research .....................................................................................1 1.3 Structure of the Report ..............................................................................................1 2. DEFINING POLYCULTURE ...........................................................................................3 2.1 Evolution of Polyculture Terms..................................................................................3 2.2 Monoculture/Polyculture cropping continuum ............................................................3 2.3 Multiple Cropping ......................................................................................................4 2.4 Sequential Cropping..................................................................................................4 2.5 Intercropping .............................................................................................................5 2.6 Other Relevant Terms ...............................................................................................6 3. WHY STUDY POLYCULTURE? A RATIONALE.........................................................10 3.1 Farming has always been predominantly polycultural..............................................10 3.2 Most farmers in the world farm polycultures ............................................................11 3.3. Interest in polycultures is growing...........................................................................13 3.4.Monoculture problems / Polyculture opportunities ...................................................14 Industrial Agricultural Intensification ........................................................................19