582 



INDEX OF SUBJECT MATTER 



Plants, response of to lime, 372. 



soil organisms injurious to, 396. 



tolerance of to soil acidity, 353. 



used for green manures, 546. 



utilization of ammonia by, 415, 450. 



utilization of organic carbon by, 402. 



utilization of organic nitrogen by, 

 411, 447. 



water requirements of, 187. 

 Plants and animals, relation to soil 

 % formation, 23. 



Plant diseases, control of in soil, 397. 

 Plant food, denned, 8. 

 Plant growth, factors for, 8. 



influence of nitrogen on, 472. 



optimum moisture for, 200. 



temperature for, 224. 

 Plant nutrients, amounts in soil, 12. 



contained in minerals, 5. 



defined, 8. 



derived from air, 9. 



derived from soil, 9. 



listed, 9. 



primary, 10. 

 Plant roots, production of carbon dioxide 

 by, 252. 



prying effect on rocks, 23. 

 Plant tissue, composition of, 100. 



method of analysis, 102. 

 Plasmolysis, defined, 290. 

 Plowing, influence of on the soil, 146. 

 Pore space of soils, calculation of, 94, 

 178. 



data on, 95. 



importance of, 95. 



nature of, 93. 

 Potash, amount in soils, 12. 



fertilizers carrying, 463. 



forms of in soil, 11. 



in farm manure, 501. 



influence on plant growth, 475. 



in liquid and solid manure, 503. 



in minerals, 6. 



loss of from soil, 555. 



loss of from farm manure, 519. 



losses from Cornell soils, 307. 



miscellaneous fertilizers of, 464. 



of food recovered in farm manure, 

 516. 

 Potash fertilizers, alunite, 465. 



feldspar, 465. 



flue dust, 465. 



Potash fertilizer, kelp, 465. 



lake salines, 465. 



leucite, 465. 



Stassfurt salts, 463. 



wood ashes, 464. 

 Potassium, see potash. 

 Potassium chloride as a fertilizer, 463. 

 Potassium nitrate, use of in litmus test, 



358. 

 Potassium sulfate as a fertilizer, 464. 

 Poultry manure, character and composi- 

 tion of, 503. 

 Potatoes, influence of manure on, 534. 

 Practical soil management, factors of, 



560. 

 Precipitation, addition of sulfur by, 469. 

 Pressure, effect on gravity water, 175. 



effect on movement of soil air, 260. 

 Process fertilizers, nature of, 446. 

 Productivity, as influenced by soil solu- 

 tion, 287. 



equation of, 327. 

 Protection, influence of on farm manure, 



525. 

 Proteid compounds, changes of in de- 

 caying manure, 510. 

 Protozoa, importance of in soil, 387. 



number of in soil, 387. 



relation of to ammonification, 387. 



types of in soil, 387. 

 Puddling of soils, 141. 

 Purchase of commercial fertilizers, 483. 

 Purchase of unmixed fertilizers, 484. 

 Putrefaction, defined, 103, 410. 



of farm manure, 508. 



products of, 411. 



Qualitative composition of drainage 

 water, 304. 

 of the soil solution, 280. 

 Quantitative composition of drainage 

 water, 304. 

 of soil solution, 282. 

 Qualitative tests for soil acidity, 358. 



compared and criticized, 359. 

 Quantitative tests for soil acidity, nature 

 of, 355. 

 value of, 357. 



Radiation, loss of heat from soil by, 240. 

 Rain-water, analysis of, 429. 

 sulfur in, 404. 



