Principles of Agronomy for Sustainable Agriculture

Preface to the First Edition
Preface
Acknowledgments
Contents
Editors and Contributors
About the Editors
Contributors
1: Agriculture and Agricultural Systems
	1.1	 Ecology and Ecosystems
	1.2	 Crop Ecology and Agricultural Systems
	1.3	 Characteristics of Agricultural Systems
	1.4	 Management of Agricultural Systems
	1.5	 Types of Agricultural Systems
	1.6	 Carrying Capacity
	Bibliography
Part I: The Crop Environment
2: The Soil: Physical, Chemical, and Biological Properties
	2.1	 Introduction
	2.2	 Dynamics of Soil Formation and Soil Loss
	2.3	 Soil Physical Properties: Texture and Structure
	2.4	 Soil Chemical Properties
		2.4.1	 pH
		2.4.2	 Redox Status
		2.4.3	 Ion Retention in Soils
			2.4.3.1	 Exchange Capacity
		2.4.4	 Salinity and Sodicity
	2.5	 Soil Biological Properties
	2.6	 Nutrient Cycles and Balances in the Soil
	2.7	 Soil Quality
		2.7.1	 Soil Erosion
		2.7.2	 Degradation of Soil Physical Properties
		2.7.3	 Degradation of Soil Chemical Properties
		2.7.4	 Soil Quality Indicators
	Bibliography
3: The Radiation Balance
	3.1	 Introduction
	3.2	 Solar Radiation
	3.3	 Solar Radiation at Ground Level
	3.4	 Longwave Radiation
	3.5	 Net Radiation
	3.6	 Intercepted Radiation
	3.7	 Radiation Interception of Trees
	3.8	 Radiation Interception of Hedgerows
	Bibliography
4: Wind and Turbulent Transport
	4.1	 Transport of Mass and Energy from Crops
	4.2	 Wind and Exchange of Matter, Energy, and Momentum
	4.3	 Profiles of Wind Speed Above Crop Canopies
	4.4	 Aerodynamic Resistance
	4.5	 Wind Speed and Turbulence at Canopy Height
	4.6	 Wind Speed Within Canopies
	4.7	 Daily and Seasonal Variation of Wind Speed and Direction
	Bibliography
5: Air Temperature and Humidity
	5.1	 Introduction
	5.2	 Atmospheric Stability
	5.3	 Basic Principles on Air Humidity
	5.4	 Temperature Profiles Within and Above Crop Canopies
	5.5	 Air Humidity Profiles Above Crop Canopies
	5.6	 Time Course of Air Temperature and Humidity
	5.7	 Sensible Heat Flux
	5.8	 Latent Heat Flux
	Bibliography
6: Soil Temperature and Soil Heat Flux
	6.1	 Introduction
	6.2	 Soil Thermal Properties
	6.3	 Soil Heat Flux
	6.4	 Spatial and Temporal Variations of Soil Temperature
	6.5	 Effects of Evaporation and Wind on Soil Temperature
	Bibliography
7: The Energy Balance
	7.1	 Introduction
	7.2	 The Energy Balance Equation
	7.3	 Relative Importance of the Components of the Energy Balance
	7.4	 Energy Balance and Nocturnal Cooling
	7.5	 Seasonal Energy Balance
	Appendix: Practical Exercises on the Energy Balance
	Bibliography
8: The Water Budget
	8.1	 Introduction
	8.2	 The Status of Water in the Soil: Water Content and Water Potential
	8.3	 Water Flow in the Soil
	8.4	 The Water Budget
	8.5	 Infiltration
	8.6	 Deep Percolation
	8.7	 Surface Runoff
	8.8	 Effective Rainfall
		8.8.1	 FAO Method
		8.8.2	 USDA-Soil Conservation Service method
	Bibliography
9: The Components of Evapotranspiration
	9.1	 Introduction
	9.2	 Measurement of Evapotranspiration
	9.3	 Evaporation from the Soil Surface
	9.4	 Analysis of Evapotranspiration with the Penman–Monteith Equation
	9.5	 Transpiration
	9.6	 Evaporation from Wetted Canopies
	Bibliography
10: Calculation of Evapotranspiration and Crop Water Requirements
	10.1	 Introduction
	10.2	 Reference ET
		10.2.1	 Method of Hargreaves
		10.2.2	 Penman–Monteith-FAO method
	10.3	 Crop Coefficients
	10.4	 Crop Coefficients of Perennial Species
	10.5	 Correction of Crop Coefficients
	10.6	 Evapotranspiration in Greenhouses
	10.7	 Calculation of Maximum ET for Designing Irrigation Systems
	10.8	 Calculation of Crop Water Requirements
	Appendices
		Appendix A: Class A Evaporation Pan
		Appendix B: Calculating Crop Coefficients Following the Model of Ritchie’s
		Appendix C
	Bibliography
Part II: Crop Productivity
11: Crop Development and Growth
	11.1	 Introduction
	11.2	 Phenological Development
		11.2.1	 Effects of Daily Mean Temperature
		11.2.2	 Vernalization and Photoperiod
		11.2.3	 Soil Water Content
	11.3	 Morphological Development
	11.4	 Growth
	Appendix
	Bibliography
12: Plant Population Density and Competition
	12.1	 Introduction
	12.2	 Density and Competition
	12.3	 Variability Between Plants and Hierarchy
	12.4	 Plant Population Density and Mortality
	12.5	 Mechanisms of Plant–Plant Competition
	12.6	 Yield and Plant Population Density
	Bibliography
13: Radiation Interception, Radiation Use Efficiency, and Crop Productivity
	13.1	 Introduction
	13.2	 Leaf-Level Photosynthesis
	13.3	 Plant Types According to Photosynthesis Mechanisms
	13.4	 Effects of Environmental Factors on Photosynthesis
		13.4.1	 Radiation
		13.4.2	 Temperature
		13.4.3	 Concentration of CO2 and Endogenous Factors
	13.5	 Respiration
	13.6	 Crop Photosynthesis
	13.7	 Intercepted Radiation
	13.8	 Radiation Use Efficiency
	13.9	 Crop Potential Productivity
	13.10	 Dry Matter Partitioning and Harvest Index
	13.11	 Alternate Bearing and Harvest Index in Fruit Tree Crops
	13.12	 Crop Factors Affecting Interception and Efficiency in the Use of Radiation
	13.13	 Environmental and Management Factors Affecting Interception and Efficiency in the Use of Radiation
	Bibliography
14: Effects of Water Stress on Crop Production
	14.1	 Introduction
	14.2	 Energy Status of Water in the Plant
	14.3	 Causes of Water Deficits
	14.4	 Effects of Water Deficits
		14.4.1	 Expansive Growth
		14.4.2	 Stomata Functioning
		14.4.3	 Crop Regulation of Transpiration
		14.4.4	 Effects on Other Processes and Interactions
	14.5	 Coupling of Photosynthesis and Transpiration
	14.6	 Quantifying the Impact of Water Deficit on Crop Production
		14.6.1	 Stewart Model
		14.6.2	 The AquaCrop Simulation Model
	Bibliography
15: Abiotic and Biotic Stress Limitations to Crop Productivity
	15.1	 Introduction
	15.2	 Nutrient Deficiency and Soil-Related Limitations of Productivity
	15.3	 Climatic Accidents
		15.3.1	 High Temperature
		15.3.2	 Hail
	15.4	 Waterlogging
	15.5	 Biotic Factors
		15.5.1	 Arthropods
		15.5.2	 Plant Pathogens
		15.5.3	 Yield Losses Due to Pests
	Bibliography
Part III: Crop Management
16: Sowing and Planting
	16.1	 Introduction
	16.2	 Crop Emergence
	16.3	 Decisions Related to Sowing
	16.4	 Sowing Date
	16.5	 Seeding Rate and Planting Density
	16.6	 Sowing Depth
	16.7	 Planting Pattern and Sowing Method
	16.8	 Additional Operations
	16.9	 Transplanting of Annuals
	16.10	 Transplanting and Grafting of Trees
	Bibliography
17: Tillage
	17.1	 Introduction
	17.2	 Objectives of Tillage
		17.2.1	 Seedbed Preparation
		17.2.2	 Weed Control
		17.2.3	 Modification of Water Balance
		17.2.4	 Other Goals
	17.3	 Influence of Soil Water Content on the Effects of Tillage
	17.4	 Conventional Tillage
	17.5	 Compaction and Plow Pan
	Bibliography
18: Soil Conservation
	18.1	 Introduction
	18.2	 Soil Erosion
	18.3	 Conservation Tillage
	18.4	 Soil Conservation Systems in Orchards and Vineyards
	Bibliography
19: Irrigation Systems
	19.1	 Introduction
	19.2	 Classification of Irrigation Systems
	19.3	 Selecting an Irrigation Method
	19.4	 Design and Management of Irrigation Systems
		19.4.1	 Surface Irrigation
		19.4.2	 Sprinkler Irrigation
		19.4.3	 Drip/Micro-irrigation
	19.5	 Drainage
	19.6	 Water Reuse
	Bibliography
20: Irrigation Scheduling Using Water Balance
	20.1	 Introduction
	20.2	 The Water Balance Equation for Irrigation Scheduling
	20.3	 Effective Rooting Depth
	20.4	 Allowable Depletion
	20.5	 Criteria for Irrigation Scheduling
		20.5.1	 Restrictions to the Dates of Irrigation
		20.5.2	 Restrictions to the Irrigation Depth
		20.5.3	 Decisions on Irrigation Dates and Depths
	20.6	 Irrigation Schedules
	Bibliography
21: Irrigation Scheduling Using Plant- and Soil-Based Methods
	21.1	 Introduction
	21.2	 Plant-Based Methods
		21.2.1	 Water Potential
		21.2.2	 Leaf Turgor Pressure
		21.2.3	 Canopy Temperature
		21.2.4	 Expansion Rate
		21.2.5	 Stem Diameter Variations
		21.2.6	 Stomatal Conductance
		21.2.7	 Sap Flow
		21.2.8	 Water Content of Plant Tissues
		21.2.9	 Qualitative Evaluation of Plant Water Status
	21.3	 Soil-Based Methods
		21.3.1	 Gravimetric Sampling of Soil Moisture
		21.3.2	 Neutron Probe
		21.3.3	 Measurements of the Dielectric Constant of the Soil
		21.3.4	 Tensiometers
		21.3.5	 Equitensiometers
		21.3.6	 Basic Criteria for Sensor Deployment
	Bibliography
22: Deficit Irrigation
	22.1	 Introduction
	22.2	 The Yield Response Function to Water
	22.3	 Deficit Irrigation in Annual Crops
		22.3.1	 Maize
		22.3.2	 Wheat
		22.3.3	 Rice
		22.3.4	 Soybean
		22.3.5	 Potato
		22.3.6	 Sorghum
		22.3.7	 Tomato
		22.3.8	 Sugarcane
		22.3.9	 Cotton
		22.3.10	 Sunflower
	22.4	 Deficit Irrigation of Fruit Trees and Vines
		22.4.1	 Regulated Deficit Irrigation
	22.5	 Deficit Irrigation at Farm Level
	Bibliography
23: Optimizing Irrigation
	23.1	 Introduction
	23.2	 Irrigation Uniformity and Efficiency
	23.3	 Quantitative Optimization of Irrigation at the Field Level
	23.4	 Irrigation Uniformity and Efficient Use of N
	23.5	 Peak and Seasonal Irrigation Demand
		23.5.1	 Seasonal Irrigation
		23.5.2	 Maximum System Capacity
	23.6	 Irrigation Duration and Interval
	Bibliography
24: Control of Salinity
	24.1	 Introduction
	24.2	 Effects of Salinity on Crops
		24.2.1	 Impacts of Salinity on Crop Productivity
		24.2.2	 Specific Toxicity
	24.3	 Irrigation Systems and Distribution of Salts
	24.4	 Salt Balance and Leaching Fraction
	24.5	 Salinity Profiles and Crop Yields
	24.6	 Required Leaching Fraction
	24.7	 Leaching for Maximum Crop Water Productivity
	24.8	 Leaching Required for Maximum Profit
	24.9	 Nonsteady Salinity
	24.10	 Sodicity and Soil Structure
	Appendix (Table 24.5)
	Bibliography
25: Fertilizers
	25.1	 Introduction
	25.2	 Fertilizers and Food Security
	25.3	 Toward More Sustainable Fertilizer Sources and Use
	25.4	 Classification
	25.5	 Fertilizer Properties
		25.5.1	 Physical Properties
		25.5.2	 Chemical Properties
		25.5.3	 Nutrient Concentration in Fertilizers
	25.6	 Straight N Fertilizers
		25.6.1	 Fertilizers with Nitrate
		25.6.2	 Fertilizers with Ammonium
		25.6.3	 Fertilizers with Nitrate and Ammonium
		25.6.4	 Urea and Related Products
	25.7	 Straight P Fertilizers
	25.8	 Straight K Fertilizers
	25.9	 Compound Fertilizers
	25.10	 Fertilizers and Products with Secondary Nutrients
	25.11	 Fertilizers and Products with Micronutrients
	25.12	 Slow-Release Fertilizers
	25.13	 Organic Fertilizers
	Bibliography
26: Nitrogen Fertilization I: The Nitrogen Balance
	26.1	 Introduction
	26.2	 N Forms in the Soil
	26.3	 N Forms Absorbed by Plants
	26.4	 Symbiotic N Fixation
	26.5	 Quantifying N Fixation
	26.6	 Transformations of N in the Soil
		26.6.1	 Mineralization and Immobilization
		26.6.2	 Nitrification
		26.6.3	 Denitrification
		26.6.4	 Ammonia Volatilization
	26.7	 Crop N Uptake
	26.8	 Nitrate Leaching
	26.9	 Soil Acidification Induced by N Fertilization
	Appendix
	Bibliography
27: Nitrogen Fertilization II: Fertilizer Requirements
	27.1	 Calculation of N Fertilizer Doses Using the Nmin Method
	27.2	 Calculation of N Fertilizer Dose Using the N Balance
		27.2.1	 Crop N Uptake (Nc)
		27.2.2	 Initial and Final Soil N and Mineralization
		27.2.3	 Fertilizer Requirement Calculation According to the N Balance
	27.3	 Within-Season Methods for Improved N Management
	27.4	 Fertilization of Fruit Trees
		27.4.1	 Mature Orchards
		27.4.2	 Young Trees
	Bibliography
28: Fertilization with Phosphorus, Potassium, and Other Nutrients
	28.1	 Introduction: Phosphorus and Potassium as Essential Nutrients
	28.2	 P in the Soil
		28.2.1	 Plant Available P in the Soil: The Soil P Test
	28.3	 Estimating the Threshold Values for the Olsen P Test
	28.4	 Potassium in the Soil
		28.4.1	 Plant Available Potassium in the Soil
	28.5	 Response of Crops to P or K Fertilizer
	28.6	 P and K Fertilization Strategies
		28.6.1	 Buildup and Maintenance Approach
		28.6.2	 Sufficiency Approach
	28.7	 Calcium and Magnesium
	28.8	 Sulfur
	28.9	 Micronutrients
	28.10	 Increasing the Efficiency of P and K Fertilizer Applications
	Appendix
	Bibliography
29: Fertigation
	29.1	 Introduction
	29.2	 Dosing Systems
	29.3	 Alternatives of Fertigation
	29.4	 Fertilizers for Fertigation
	29.5	 Quality of Water for Fertigation
	29.6	 Calculation of Stock Solutions
	29.7	 Fertigation Control
	29.8	 Calculation of Complete Nutrient Solutions
	29.9	 Examples of Fertigation Programs
	Bibliography
30: Soil Improvement and Reclamation
	30.1	 Introduction
	30.2	 Soil Health
	30.3	 Soil Organic Matter
		30.3.1	 Soil Organic Matter Losses
		30.3.2	 Improving Soil Organic Matter
	30.4	 Improving Soil Physical Properties
		30.4.1	 Soil Compaction
		30.4.2	 Stones
		30.4.3	 Other Techniques
	30.5	 Reclamation of Saline Soils
	30.6	 Reclamation of Sodic Soils
	30.7	 Reclamation of Acidic Soils
	30.8	 Regenerative Agriculture
	Bibliography
31: Manipulating the Crop Environment
	31.1	 Introduction
	31.2	 Effects of Wind on Crops
	31.3	 Wind Forces on Plants, Lodging, and Windthrow
	31.4	 Windbreaks
	31.5	 Wind and Turbulence in the Sheltered Zone
	31.6	 Establishment and Maintenance of Windbreaks
	31.7	 Microclimate Changes in the Protected Area
	31.8	 Scattered Windbreaks
	31.9	 The Importance of Soil, Air, and Crop Temperatures
	31.10	 Slope and Aspect
	31.11	 Mulching
	31.12	 Artificial Soil Heating
	31.13	 Modifying Canopy Temperature
	31.14	 Greenhouses
	Bibliography
32: Frost Protection
	32.1	 Introduction
	32.2	 Effects of Frost on Crop Production
	32.3	 Minimum Canopy Temperature
	32.4	 Frost Types
	32.5	 Climatology of Frosts
	32.6	 Risk of Extreme Cold Temperatures
	32.7	 Frost Protection
		32.7.1	 Passive Protection Methods
			32.7.1.1	 Site Selection
			32.7.1.2	 Selection of Species, Cultivars, and Cultural Techniques
			32.7.1.3	 Soil Management
		32.7.2	 Active Protection Methods
			32.7.2.1	 Increasing Radiation Interception
			32.7.2.2	 Air Mixing
			32.7.2.3	 Heating the Air or the Canopy
			32.7.2.4	 Irrigation
			32.7.2.5	 Avoiding Failure of Active Methods
	Bibliography
33: Control of Weeds and Other Biotic Factors
	33.1	 Introduction
	33.2	 Characteristics of Weeds
		33.2.1	 Dispersal of Weeds
		33.2.2	 Persistence of Weeds
	33.3	 Classification of Weeds
	33.4	 Crop-Weed Interactions
	33.5	 Economic Threshold
	33.6	 Pest Control
		33.6.1	 Mechanical Control
		33.6.2	 Other Control Techniques
	33.7	 Using Pest-Resistant Cultivars
	33.8	 Weed Management
	Bibliography
34: Application of Herbicides and Other Biotic Control Agents
	34.1	 Introduction
	34.2	 Pesticides
	34.3	 Application of Pesticides
	34.4	 Drift
	34.5	 Persistence of Pesticides
	34.6	 Herbicides
		34.6.1	 General Characteristics
		34.6.2	 Selectivity of Herbicides
	34.7	 Insecticides
	34.8	 Fungicides and Control of Diseases
	34.9	 Calculation of the Volume Application Rate of Pesticides
	34.10	 Calculation of Spray Volumes for Fruit Tree Orchards
	Bibliography
35: Harvest and Conservation
	35.1	 Introduction
	35.2	 Harvest Operations
	35.3	 Yield Losses During Harvest
	35.4	 Agricultural Operations Affected by Harvest
	35.5	 Harvest of Grains and Seeds
	35.6	 Harvest of Forage Crops
	35.7	 Harvest of Underground Organs
	35.8	 Harvest of Fruits and Vegetables
	Appendix
	Bibliography
36: Cropping and Farming Systems
	36.1	 Introduction
	36.2	 Types of Cropping Systems
	36.3	 Intercropping
	36.4	 Agroforestry Systems
	36.5	 Crop Rotations
	36.6	 Farming Systems
	36.7	 Agricultural Ecosystem Services
	Bibliography
37: Energy Consumption in Agriculture
	37.1	 Introduction
	37.2	 Energy Requirements of Farming
	37.3	 Energy Requirements of Tillage
	37.4	 Energy Requirements of Irrigation
	37.5	 Energy Requirements of Fertilization
	37.6	 Energy Requirements of Human Labor
	37.7	 Farm Energy Outputs and Efficiency
	37.8	 CropEBal
	Bibliography
38: Remote Sensing
	38.1	 Introduction
	38.2	 Basic Principles of Remote Sensing
	38.3	 Reflectance and Spectral Signatures
	38.4	 Remote Sensing Resolution
	38.5	 Sensors and Platforms for Remote Sensing
	38.6	 Applications: Reflectance and Vegetation Indices
	38.7	 Applications: Thermal and Active Sensors
		38.7.1	 LiDAR (Light Detection And Ranging)
		38.7.2	 RADAR (RAdio Detection And Ranging) or SAR (Synthetic Aperture Radar)
	38.8	 Phenomics
	Bibliography
39: Site-Specific Agriculture
	39.1	 Introduction
		39.1.1	 Assessing Variability
		39.1.2	 Managing Variability
		39.1.3	 Output Evaluation
	39.2	 Positioning and Automation
	39.3	 Definition of Management Zones
		39.3.1	 Yield Maps
	39.4	 Site-Specific Irrigation
		39.4.1	 Precision Irrigation Technology
		39.4.2	 Opportunities Provided by Site-Specific Irrigation
	39.5	 Site-Specific Nutrient Management
		39.5.1	 Nitrogen
		39.5.2	 Other Nutrients
	39.6	 Site-Specific Crop Protection
		39.6.1	 Site-Specific Weed Management
			39.6.1.1	 Map-Based Approach
			39.6.1.2	 Real-Time Approaches
		39.6.2	 Site-Specific Pest and Disease Management
		39.6.3	 Weed, Pest, and Disease Control Operations in SSCP
	Bibliography
40: Crop Models
	40.1	 Introduction
	40.2	 Basic Concepts
		40.2.1	 Model Formulation
		40.2.2	 Calibration and Validation
		40.2.3	 The Need for Models in Agriculture
	40.3	 Classification of Crop Models
		40.3.1	 Empirical Models
		40.3.2	 Mechanistic Crop Models
	40.4	 Machine Learning
	40.5	 Decision Support Systems in Agriculture
	Bibliography
41: Climate Change Adaptation and Mitigation
	41.1	 Introduction
	41.2	 The Carbon Cycle
	41.3	 Main Effects of Climate Change on Crop Production
	41.4	 GHG Emissions from Food Production
	41.5	 Crop Adaptation to Climate Change
		41.5.1	 Annual Crops
		41.5.2	 Tree Crops and Vines
	41.6	 Mitigation
		41.6.1	 The Role of Conservation Agriculture
		41.6.2	 Permanent Crops and Forests
	Bibliography
42: Agronomy and the Sustainability of Crop Production
	42.1	 Introduction
	42.2	 Climate, Soil, and Water
		42.2.1	 Soil Degradation
		42.2.2	 Water Scarcity
	42.3	 The Role of Plant Breeding
	42.4	 Alternative Agricultural Systems: Organic Farming
	42.5	 Agriculture as an Energy Source
	42.6	 The Role of Research, Extension, and Information/Communication Technologies
	42.7	 Food Security and Food Safety
	Bibliography
43: Quantitative Analysis of Crop Production in an Irrigated Farm (Part I)
	43.1	 Introduction
	43.2	 Practical Project Statement
	43.3	 Analysis of Agrometeorological Data
	43.4	 Productivity
		43.4.1	 Leek Sown 1 October
		43.4.2	 Pepper Sown 1 May
	43.5	 Seed Rates
		43.5.1	 Leek
		43.5.2	 Pepper
	43.6	 Irrigation Schedules
		43.6.1	 Leek
		43.6.2	 Pepper
	43.7	 Leaching Fraction Required
		43.7.1	 Leek
		43.7.2	 Pepper
		43.7.3	 Farm
	43.8	 Fertilizer Program
		43.8.1	 N Fertilization
		43.8.2	 P and K Fertilization
		43.8.3	 Cost of the Fertilization Program
		43.8.4	 Comparison with FertiliCalc Outputs
	43.9	 Crops Calendars and Energy Requirements
		43.9.1	 Crop Calendars
		43.9.2	 Energy Requirements
		43.9.3	 Comparison with CropEBal Outputs
	Bibliography
44: Quantitative Analysis of Crop Production in an Irrigated Farm (Part II)
	44.1	 Introduction
	44.2	 Probability of Frost
		44.2.1	 Probability of Frost After March 1
		44.2.2	 Probability of Frost Before December 1
	44.3	 Certainty of Not Exceeding a Minimum Temperature
	44.4	 Date of First Autumn Frost
	44.5	 Transpiration of an Isolated Tree
	44.6	 Calculation of ET for Designing an Irrigation System
	44.7	 Calculation of ET Inside an Unheated Greenhouse
	44.8	 Optimum Seasonal Irrigation
	44.9	 Comparison of Alternative Water Qualities and Prices
	44.10	 Leaching Fraction to Maximize Crop Water Productivity
		44.10.1	 Leek
		44.10.2	 Pepper
	44.11	 Sulfur Exports in a Rotation
	44.12	 Selection of the Best Fertilizers
	44.13	 Leaching Index
	44.14	 Calculation of Soil Erosion
	44.15	 Calculation of Runoff
		44.15.1	 Leek Plot
		44.15.2	 Pepper Plot
	44.16	 Calculation of the Maximum Temperature Inside an Unheated Greenhouse
	44.17	 Shading by a Windbreak
	44.18	 Frequency of Days Suitable for Pesticide Applications
	Bibliography
Index