392 



INDEX 



Muck soU, as soil type, 25 



advantages in farming, 293 



characteristics of, 293 



defined, 16, 25 



fertiUzers for, 199, 203, 297-300 



least desirable, 294 



most desirable, 294 



origin of, 16, 17 



problems in cropping, 294 



value of, 16 



why better than peat, 41 

 Mulches, 104. (See Soil mulch) 

 Muriate of potash, fertilizer, 202 



Natural systems of tihng, 120. 121 

 Nitrate fertilizers. (See Nitrogen fertilizers) 



of soda, 197 

 Nitrates, defined, 174, 175 

 Nitrification, explained, 173, 175 

 destrQys organic matter, 175 

 favored by cultivation, 357 

 laboratory exercises on, 185 

 retarded by fall plowing, 357 

 Nitrifying bacteria, 174, 175 



lacking in some soils, 175 

 Nitrogen, defined, 30, 31 



amount removed by crops, 62, 63 



by fruit, ^ 69 

 an account with, in farming, 347 

 Analyzing soils for, 359 

 balance sheet in farming, 347-353 

 contained in feeds, 383 

 fertilizers, 196 

 function of, in plants, 55 

 gain m farming, 351-353 

 how held in soils, 33 



much fixed by bacteria, 178 

 plants secure, 35, 36 

 in relation to fertility, 187 

 losses by soil leaching, 351 



from manure, 216, 350 

 problem in sand farming, 310 



solved by legumes, 197 

 supply of, in soils, 70, 71 

 Nitrogen fertilizers, 196 = 



availability of, 196 

 for sands, 310 

 leached from soil, 196, 213 

 needs increased, 209 

 fixation, defined, 178 



amount of nitrogen fixed, 178, ISO 

 by molds, 178 

 by soil bacteria, 175-180 

 by use of electricity, 178 

 how accomplished, 179 

 Nitrogen-phosphorus balance sheet, 347-353 

 illustrated, 352-353 

 in grain farming, 348 

 on a dairy farm, 348 

 Nodule bacteria, 172, 175, 180 

 are plants, 178 

 conditions favoring, 184 

 different kinds of, 182 

 discovery of, 176 

 how they work, 179 

 in relation to crop failure, ISl 

 same for different legumes, 182 

 Nodules, defined, 179 

 alfalfa, 178 

 crimson clover, 177 

 garden pea, 183 

 inside of lupine, 179 

 medium red clover, 177 

 soybean, 176 

 JSFutrient solution for plants, 58 



Oats, elements removed by, 62 

 for green manure, 192 

 for sand f aiming, 317 

 response to phosphates, 189 

 rotations for, 275, 276 

 vs. barley to grow, 66 

 where grown, 276 

 Ohio grain-farming trial, 345 

 gram vs. stock farming, 346 

 test plots in field, 361-363 

 One-crop system, defined, 264 



danger m, 264 

 Onions, elements removed by, 62 



root system of, 68 

 Organic matter, defined, 6 



aids decay of soil, 173 

 chemical composition of, 30, 175 

 decomposition of, 175 

 destroyed by nitrification, 175 

 fertility relations, 356 

 improves tilth, 266, 323 

 increases water-holding capacity, 



98, 102 

 increased by rotation, 265 



by fertilization, 266 

 in sand farming, 310 

 laboratory exercises on, 223 

 lessens soil erosion, 287 

 maintained by green manures, 191 

 maintains farming system, 191 

 makes fertilizers more effective, 173 

 rapid reduction of, 206 

 rotations to increase, 274 

 Organisms in soil, 13, 171 

 causing decay, 171, 172 

 in relation to fertility, 171 

 Osmosis, defined, 54 

 Outlet ditch, defined, 115 



of tile drains, 122, 123 

 Oxygen, defined, 0, 30 

 and germination, 48 

 laboratory exercises on, 58 



Parallel system in tiling, 122 

 Pasture on sands, 317 

 Pasturing and soil erosion, 286 



loss of elements in, 351 

 Peaches, elements removed by, 69 

 Peanuts, response to liming, 233 



rotations for, 279 

 Pears, elements removed by, 69 

 Peas, elements removed by, 62, 63 

 injury from blight, 257 

 response to limmg, 233 

 rotations for, 27 G, 278, 280 

 Peat soil, advantages in cropping, 293 



as soil type, 25 



bogs on, 297 



burning of, 295 



characteristics of, 293 



cabbage on, 204, 305 



clover for, 304 



corn on, 187, 201, 236, 296, 298, 

 303, 305 



crop rotation on, 304 



crops for, 303, 305 



deficient in mineral elements, 72 



defined, 16, 25 



drainage for, 294 



extensive farming on, 306, 307 



fertiHzers f or, 187, 201, 297-300, 303 



firm seed bed important, 302 



for blueberries, 234 



for cranberries, 234 



for sand improvement, 315 



