Front Cover; Advances in Agronomy, Volume X; Copyright Page; Contents; Contributors to Volume X; Preface; Chapter 1. Agronomic Trends and Problems in the Great Plains; I. The Great Plains Area; II. Field Crops; III. Pasture and Range Crops; IV. Soil Moisture Conservation; V. Soil Fertility Problems; VI. Irrigation; VII. Wind Erosion Problems; References; Chapter 2. Changing Concepts of Plant Nutrient Behavior and Fertilizer Use; I. Introduction; II. Diagnostic Techniques as a Guide; III. Sources of Nutrients; IV. Fertilizer Placement; V. Time of Application and Residual Value of Fertilizers.

VI. Lime Level and Response to FertilizersVII. Moisture and Fertility; VIII. Grower Demands; IX. Economics of Fertilizer Use; X. In the Future; References; Chapter 3. Race 15B of Wheat Stem Rust-What It is and What It Means; I. Why Race 15B Is Notorious; II. The History of Race 15; III. The Early History of 15B; IV. The Prevalence of Race 15 and 15B, 1918-1949; V. The Explosive Spread and Establishment of Race 15B in 1950-1951; VI. The Percentage Prevalence of 15B in the United States, 1950-1956; VII. The Scientific and Practical Importance of 15B.

VIII. Vicissitudes in Breeding Rust Resistant Wheats in the PastIX. The Stem-Rust-Free Era in Spring Wheat, 1938-1949; X. The Virulence of 15B for Previously Resistant Varieties; XI. Problems in Breeding for Resistance to 15B; XII. Increased Complexity in Physiologic Races of Wheat Stem Rust Since 1950; XIII. Race 7 of Oat Stem Rust Also Explodes in 1950; XIV. Shifting Populations of Physiologic Races of Other Pathogens, Especially Crown Rust of Oats; XV. A Three-Pronged Attack on 15B and Other Virulent Races of Cereal Rust; XVI. Conclusion; References.

Chapter 4. Australian Soils and Their Responses to FertilizersI. Introduction; II. The Climate and Land Use of Australia; III. The Australian Soil Landscape; IV. History of Fertilizer Use in Australia; V. Phosphorus and Nitrogen Deficiencies; VI. Deficiencies of Other Major Elements; VII. Trace Element Deficiencies; VIII. Conclusion; Acknowledgments; Appendix; References; Chapter 5. Castorbeans: A New Oil Crop for Mechanized Production; I. Introduction; II. Botany; III. Breeding; IV. Production; V. Future for Castorbeans; References; Chapter 6. Safflower; I. Introduction; II. Distribution.

III. AdaptationIV. Botany and Inheritance; V. Cyto-taxonomy; VI. Utilization; VII. Improvement; VIII. Conclusions; References; Chapter 7. Reactions of Ammonia in Soils; I. Introduction; II. Mechanisms of Ammonia Sorption; III. Reactions of Ammonia with Soil Constituents; IV. Nonbiological Oxidation of Ammonia; V. Factors Affecting Sorption and Loss in the Soil; VI. Effects of Ammonia on Soil Properties and Organisms; VII. Summary; References; Chapter 8. New Grasses and Legumes for Soil and Water Conservation; I. Introduction; II. The Northeastern Region; III. The Southeastern Region.