750 



INDEX 



Air-slaked lime, 539. 

 Alga?, aid to nitrogen fixation, 464. 

 Alinit, nitro-culture, 463. 

 Alkali in soils, 392. 



accumulation of, 397. 



and irrigation, 397. 



and the mulch, 282. 



block alkali, 392. 



composition, 393. 



correction, 399. 



control, 402. 



effect on plants, 394. 



effect of method of irrigation, 706. 



formation of, 724. 



outfit for testing, 728. 



salts in soil, 391. 

 Alkali land, drainage of, 659. 

 Alkali lands, management of, 399. 

 Alkali lands of foreign countries, 398. 

 Alkali spots, 402. 

 Alluvial soils, described, 39. 



distribution of, 41. 



humus and nitrogen in, 148. 

 Alternaria, disease organism, 426. 

 Alternate cropping, 714. 

 Aluminum, 6. 

 Aluminum phosphate, 337. 

 Aluminum in soil separates, 102. 

 Amendments of the soil, 534. 



calcium sulfate, 542. 



calcium carbonate, 540. 



caustic lime, 539. 



common salt, 543. 



effect on nitrification, 536. 



effect on tilth and bacteria, 534. 



effect on toxic materials, 537. 



liberation of plant-food, 535. 



lime and granulation, 193. 



muck, 545. 

 Amid nitrogen, plant-food, 497. 

 Ammonia, absorption of, 353, 366. 



as plant-food, 494. 



from plant decay, 139. 



salts and acidity, 381. 



test for acidity, 387. 

 Ammonification in soil, 446. 

 Ammonification, effect of partial ster- 

 ilization, 470. 

 Ammonium sulfate, as fertilizer, 499. 

 Amount of water to use in irrigation, 710. 

 Anaerobic bacteria, 433. 

 Anaerobic bacteria and putrefaction, 



444. 

 Anaerobic fermentation of manure, 593. 

 Analysis, mechanical, of soil, 97, 104, 

 107. 



Analysis, mineralogical, 100. 



of adobe. I 



of air, 139. 478. 



of alkali, 393. 



of arid and humid soils, 72, 147. 



of coastal plain soils, 70, 66. 



of crops, 419. 



of cumulose soil, 37. 



of cyanamid, 503. 



of drainage water, 351, 371, 374, 500 



of gases from manure, 594. 



of glacial soils, 68, 70. 



of granite and residual soil, 27. 



of humus, 149. 



of humus ash, 145. 



<>f limestone and residual clay, 27, 33, 

 68. 



of litter, 580. 



of loess, 60. 



of manure, 581, 582, 583, 584, 588. 

 595. 



of marl, 38. 



of residual soils, 66, 68, 70. 



of soils, humus, 147, 148. 



of soil, organic matter, 146. 



of soil separates, 101, 102. 



of water extract, 348. 

 Animals, capacity to produce manure, 

 587. 



effect on granulation, 192. 



effect on composition of manure, 

 581, 582, 584. 



soil-forming agent, 18. 

 Antiseptics, treatment of soil with, 465. 

 Apatite, mineral, 9. 



as a fertilizer, 512. 

 Apophyllite, solubility, 339. 

 Apparent specific gravity, 113. 

 Application of water, time, 709. 

 Arginine, plant-food, 497. 

 Arid and humid soils, 71. 



composition of, 72. 



properties of, 72, 82. 



soil particles, composition of, 100, 

 101. 

 Arrangement of soil particles, 108. 

 Artificial mulch, 273. 

 Ash composition of humus, 145. 

 Ash constituents of plants, 416. 

 Aspergillus niger in soil, 427. 

 Atmospheric pressure affects soil air, 



484. 

 Attraction of soil particles, 206. 

 Auger, for soil examination, 727, 732. 

 Augite, 9. 

 Availability of organic fertilizer, 510. 



