LITMIR.BIZ

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Conditions necessary for leaf work 109 How the work of leaves is interfered with 115 XIV. Stems 120 What are stems for? 120 How the work of the stem may be interfered with 126 XV. Flowers 128 Function of flowers 128 Parts of flowers 129 Functions of the parts: Cross pollination 130 Value of a knowledge of the flowers 134 Fruit 136

PART II

       Table of Contents

      Soil Fertility As Affected By Farm Operations And Farm Practices

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Chapter		Page
XVI.	A Fertile Soil	141
	Physical properties:
	Power to absorb and hold water
	Power of ventilation
	Power to absorb and hold heat	142
	Biological properties	143
	Nitrogen-fixing germs	144
	Nitrifying germs	145
	Denitrifying germs	147
	Chemical properties:
	Nitrogen in the soil
	Phosphoric acid in the soil
	Potash in the soil
	Lime in the soil
	Great importance of physical properties	147
	Maintenance of fertility	150
XVII.	Soil Water	151
	Importance of soil water	151
	Necessity of soil water	151
	Sources and forms of soil water	153
	Too much water	154
	Not enough water	154
	Loss of soil water	155
	How some farm operations influence soil water	156
	Hoeing, raking, harrowing and cultivating	158
	Manures and soil water	159
	Methods of cropping and soil water	159
	Selection of crops with reference to soil water	160
XVIII.	The After-cultivation of Crops	164
	Loss of water by evaporation	164
	Loss of water through weeds	165
	Saving the water	165
	Time to cultivate	166
	Tools for after-cultivation	167
	Hilling and ridging	169
XIX.	Farm Manures	171
	The functions of manures and fertilizers	171