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An Investigation Into Ecological Farming Systems on the Canadian Prairies

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An Investigation Into Ecological Farming Systems on the Canadian Prairies An Investigation into Ecological Farming Systems on the Canadian Prairies by Calvin Dick A Thesis submitted to the Faculty of Graduate Studies of the University of Manitoba in partial fulfilment of the requirements of the degree MASTER OF SCIENCE Department of Plant Science University of Manitoba Winnipeg Copyright ©Calvin Dick 2016 ii Table of Contents ABSTRACT ................................................................................................................................................ vii ACKNOWLEDGEMENTS .............................................................................................................................. viii LIST OF TABLES ............................................................................................................................................. ix LIST OF FIGURES ........................................................................................................................................... xi 1. INTRODUCTION ......................................................................................................................................... 1 2. LITERATURE REVIEW ................................................................................................................................. 5 2.1 Perennial Grain Overview ................................................................................................................... 5 2.1.1 Background .................................................................................................................................. 5 2.1.2 Advantages ................................................................................................................................... 5 2.1.3 Criticism ....................................................................................................................................... 8 2.1.4 Strategies for Perennial Grain Crop Development ...................................................................... 9 2.2 Intermediate Wheatgrass (Thinopyrum intermedium) ..................................................................... 11 2.2.1 Background ................................................................................................................................ 11 2.2.2 Seed and Biomass Production.................................................................................................... 12 2.3 Agronomic Strategies for Increasing the Sustainability of Perennial Grain Systems ........................ 15 2.3.1 Legume Integration and Management in Perennial Systems .................................................... 15 2.3.2 Livestock Integration with Seed Producing Crops ..................................................................... 17 2.4 Ecological Farming Systems .............................................................................................................. 19 2.4.1 Agroecology ............................................................................................................................... 20 2.4.2 Successional Spectrum ............................................................................................................... 21 2.4.3 Conservation Agriculture ........................................................................................................... 23 2.4.4 Organic Agriculture .................................................................................................................... 24 2.4.5 Rangeland and Holistic Grazing Management ........................................................................... 26 2.4.6 Influential Individuals ................................................................................................................. 28 2.4.7 Permaculture ............................................................................................................................. 29 2.4.8 Management of non-field farm elements and farmscaping ...................................................... 33 2.5 Farm System Analysis ........................................................................................................................ 35 2.5.1 Farm Design and Innovation ...................................................................................................... 37 2.5.2 Farm Typology ............................................................................................................................ 38 iii 2.5.3 Farm System Research Trials ..................................................................................................... 38 2.5.4 Landscape Distribution-Based Studies ....................................................................................... 39 2.5.5 Whole Farm Case Studies .......................................................................................................... 39 3.0 EFFECTS OF LEGUME INTERCROPPING AND RESIDUE MANAGEMENT ON INTERMEDIATE WHEATGRASS (Thinopyrum Intermedium) GRAIN AND BIOMASS PRODUCTION ...................................... 41 3.1 Introduction ...................................................................................................................................... 41 3.2 Materials and Methods ..................................................................................................................... 43 3.2.1 Site Description .......................................................................................................................... 43 3.2.2 Experimental Design .................................................................................................................. 44 3.2.2.1 Seeds, Seeding and Sources ................................................................................................ 44 3.2.2.2 Harvest Details .................................................................................................................... 45 3.2.2.3 Grazing Details .................................................................................................................... 45 3.2.3 Data Collection ........................................................................................................................... 46 3.2.3.1 Biomass Sampling ............................................................................................................... 46 3.2.3.2 Processing and Drying ......................................................................................................... 47 3.2.3.3Seed Processing and Cleaning.............................................................................................. 48 3.2.3.4 Tiller Counts, Legume Cover Estimation, and IWG Nutrient Content ................................ 49 3.2.4 Statistical Analysis ...................................................................................................................... 49 3.2.5 Issues .......................................................................................................................................... 50 3.3 Results ............................................................................................................................................... 52 3.3.1 Grain Yield and Harvest Index .................................................................................................... 52 3.3.2 Plant Biomass ............................................................................................................................. 54 3.3.3 Legume Cover, Tiller Counts, and Nutrient Data ....................................................................... 59 3.4 Discussion .......................................................................................................................................... 61 3.4.1 Overall Yield ............................................................................................................................... 61 3.4.2 Legume Treatments ................................................................................................................... 63 3.4.2.1 Sweet Clover ....................................................................................................................... 66 3.4.2.2 White Clover ....................................................................................................................... 67 3.4.2.3 Alfalfa .................................................................................................................................. 68 3.4.3 Residue Management ................................................................................................................ 69 3.4.4 Tiller Counts and Nutrient Concentrations ................................................................................ 72 3.5 Conclusions ....................................................................................................................................... 73 iv 3.5.1 Short term system dynamics ..................................................................................................... 73 3.5.2 Future Dynamics ........................................................................................................................ 75 4.0 ECOLOGICAL FARMING SYSTEMS ON THE CANADIAN PRAIRIES .......................................................... 76 4.1 Introduction ...................................................................................................................................... 76 4.1.1 Project Justification ...................................................................................................................
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