INDEX 



393 



Peat soil, grain on peat, 300, 305 

 home projects on, 308 

 how wrongly advertised, 72 

 least desirable, 294 

 Ume for, 245. 301 

 manure for, 300 

 mild alkali on, 236 

 most desirable, 294 

 nitrogen f ertihzer for, 299 



problem on, 301 

 origin of, 16, 17 

 phosphates for, 299, 300 

 plowing, 295, 296 

 potash fertilizer for, 204, 299 

 problems m farming, 294 

 rape for, 306 

 rock phosphate on, 200, 201, 299, 



300 

 roller for, 155, 302 

 seed-bed preparation, 297, 302 

 types of farming on, 306, 307 

 value of, 16, 294, 307 

 when acid, 236 



non-acid, 236 

 why deficient m K and P, 40 

 wood ashes for, 301 

 Percolation, defined, 94 



aided by roots and worms, 95 

 importance of, 95 

 Phosphate fertilizers, 197 

 acid vs. rock, 202 

 availability of, 197 

 choice of, 201 

 cost of, 207 



determining equivalents, 198 

 expressing equivalents, 198 

 fertility relations, 222 

 for acid soils, 202 

 for clay soils, 324' 

 for marsh soils 201, 299 

 for reinforcing manure, 221, 222 

 for sandy soils, 312 

 for* soil improvement, 326 

 home projects on, 253 

 results from, 188, 189, 199-201 

 rock vs. acid phosphate, 202 

 soils needing, 199 

 testing value of, 189, 364, 365 

 rock. (See Rock phosphate) 

 "Phosphoric acid," defined, 30, 34 

 Phosphorus, defined, 30, 32 



amount removed by crops, 62, 63 



by fruit, 69 

 analysis, value of, 359 

 available rather than total, 199 

 contained in feeds, 383 

 distribution of, in plants, 63 

 fertility relations, 85, 187 

 function of, in plants, 55 

 lost in growing tobacco, 267 

 purchased in feeds, 199 

 supply of, in soils, 70, 72 

 Phosphorus-nitrogen balance sheet, 347 

 illustrated, 352, 353 

 in grain farming, 348 

 on a dairy farm, 348 

 Planker, 154 

 Plant, a factory, 50 



growth of, affected by soil, 34, 51 

 by temperature, 51 

 in nutrient solutions, 58 

 laboratory exercises on, 59 

 relation to^ soil and air, 34, 36 

 to animals, 36 

 Plants, conditions for growth of, 47 



Plants, feeding power of, 66 

 great work of, 37 

 growth of in darkness, 59 

 subjects for study, 67 

 Plant-food elements, defined, 54 



account with m farming, 347-353 

 amount regained in manure, 350 

 available vs. total, 356 

 crops feed on, 61 

 exchange of, in farming, 350-353 

 gam and loss of, in farming, 349 

 gain of, how determined, 351-353 

 gained from purchased feeds, 350- 



352 

 in soils, 71 

 in subsoils, 72 

 laboratory exercises on, 58 

 loss and gain of, illustrated, 349, 350 

 losses of, how determined, 351-353 

 lost by pasturing, 351 

 by soil erosion, 283 



leaching, 349 

 in feeding transaction, 349, 350 

 materials supplying, '190 

 total vs. available amount, 356 

 Planting and seeding, 156 

 Plow, 138-150 



best time to, 144 

 disk, 142 



equipment for the, 138 

 gang, 149, 150 

 general purpose, 141 

 hillside, 147 

 its work, 138-140 

 left-hand, 148 

 parts of a, 140 

 prairie breaker, 144 

 right-hand, 148 

 sod, 141 

 stubble, 141 

 subsoil, 145 

 walking, 140, 141 

 Plowing, 138-150 



chain for turning weeds, 194 

 clay soils, 325 

 fall, 144, 146 

 hillside, 147, 149 

 moderately deep best, 146 

 no substitute for liming, 248 

 retarded nitrification, 357 

 sands, 315 

 sod, 140, 143 

 spring, 146 

 stubble land, 138 

 tractor, 149, 150 

 vs. disking, 159 

 when green manuring, 193 

 with subsoil plow, 145 

 Plow sole, defined, 147 

 Pot tests for soil needs, 204, 223, 298, 360 



not fully reliable, 204, 360 

 Potash, defined, 30, 34 



true meaning of, 34 

 Potash fertilizers, 202 



absorlied by soils, 213 



availability of, 202 



cost of, 207 



determining equivalents, 202 



expressing equivalents, 202 



for clay soils, 324 



for marsh lands, 203, 204, 297 



for peat soils, 203, 208, 297 



for sands, 312, 313 



soils needing, 360 



sources of, 202 



