CHAPTER XVII.. Relations of Soils and Plant Growth to Heat, 301.—Temperature

RELATIONS OF SOILS AND PLANT GROWTH TO HEAT, 301.—Temperature of Soils, 301.—Water Exerts Controlling Influence, 301.—Cold and Warm Rains, 302.—Solar Radiation, 302.—Penetration of the Sun’s Heat into the Soil, 302.—Change of Temperature with Depth, 303.—Surface Conditions that Influence Soil Temperature, 303.—Heat of High and Low Intensity, 304.—Reflection vs. Dispersion of Heat, 304.—Influence of Vegetation, and of Mulches, 305.—Influence of the Nature of the Soil-Material, 306.—Influence of Evaporation, 307.—Formation of Dew, 307.—Dew rarely adds Moisture, 308.—Dew within the Soil, 308.—Plant Development under Different Temperature-Conditions, 309.—Germination of Seeds; Optimum Temperature for each Kind, 309.—Artificial Heating of Soils; by Steam Pipes or Water, 310.