INDEX 



289 



Clay, formation of 54 



particles 12 



sedimentation of 267 



Clover as manure 127 



nitrogen returned by. 



102, 112, 245 



root nodules 104 



manuring of 226 



Coaf ashes 184 



Color of plants, influenced 



by nitrogen 98 



of soils 41 



and soil temperature . . 265 

 Combination of elements in 



soils 58 



Commercial fertilizers ..196-214 



abuse of 206 



and tillage 206 



and farm manures. ... 214 



composition of 197 



extent of use 196 



field tests with 208 



for special crops 213 



home mixing of 204 



inspection of 200 



judicious use of 207 



mechanical condition 



of 200 



misleading statements. 203 



nitrogen of 200 



phosphoric acid of 201 



plant food in 199 



potash of 202 



preparation of 197 



valuation of 203 



variable composition 197 



Composition of soils 80, 82 



Composting manures 149 



Corn, fertilizers for 213 



food requirements of. .221 

 and manure 155 



Cotton, fertilizers for 224 



Cottonseed meal 125 



Cow manure 141 



Crop residue 232 



Cultivation after rains 32 



and bacterial action.. 252 



shallow surface 30 



and soil moisture .... 265 

 Cumulative fertility 259 



Davy, work of 3 



Deficiency of nitrogen 209 



of phosphoric acid . . 210 



of potash 210 



of two elements 211 



Denitrification 117 



De Saussure, work of 3, 99 



Diseases of soils 256 



Dissolved bone 1 74 



Distribution of soils 50 



Drainage . 28, 40 



Dried blood 121 



Early truck soils 17 



Electricity of soil 43 



Evaporation 27 



Excessive use of fertilizers.. 21 2 



Experiments 261, 274 



Experimental plots 208 



Fallow fields 119 



Fall plowing 34 



Farm manures 131, 159 



and commercial fertil- 

 izers 214 



Feldspar 52, 199 



Fermentation of manures. . 147 

 Fertility, conservation of 241 



importance of p . 260 



removed in crops 216 



