532 



EXPERIMENT STATION EECORD 



Soil— Continued. 



acidity— continued . 



as affected by organic matter, (37) 718. 

 affected by sulphur, (31) 727. 



blast-furnace slag for, (36) 728. 



cause, (37) 623, 624. 



cause and detection, (34) 419. 



cause and nature, (35) 722. 



correcting, (26) 723; (35) 727; (36) 429, 519; 

 (38) 819. 



determination, (30) 715; (31) 112; (32) 30, 

 610; (33) 206; (34) 609; (35) 23, 503; (36) 

 117, 210, 505; (38) 419, 720; (40) 213. 

 acidity, effect on — 



availability of ammonium sulphate, (37) 

 521. 



grasses, (37) 446; (40) 125. 



nitrogen-assimilating bacteria, (39) 722, 723. 



vetch and oats, (40) 134. 

 acidity- 

 experiments, (35) 324. 



limestone action on, (40) 423. 



litmus-paper test, (39) 515. 



measuring by sugar inversion, (40) 123. 



nature, (40) 123. 



neutralizing, (32) 812; (37) 815; (40) 125, 815. 



notes, (29) 623, 816; (31) 322; (35) 120; (38) 

 298. 

 acidity, relation to — 



green manuring, (38) 20; (39) 216, 326, 424. 



growth of orchids, (40) 812. 



lime and potash content, (40) 812. 



mold action, (40) 319. 



plant cover, (27) 29. 



plant growth, (39) 513; (40) 324. 

 acidity, studies, (26) 813; (28) 708; (29) 815; (31) 

 618; (32) 29, 212; (36) 813; (37) 24, 118; (38) 20, 

 511; (39) 514, 620; (40) 319, 620. 

 air- 

 carbon dioxid content, (28) 320; (39) 516. 



composition, (40) 619. 



notes, (33) 618; (34) 514. 



movement, (26) 619. 

 aldehydes, studies, (40) 22. 

 alkalinity, relation to plant chlorosis, (31) 50. 

 amendments, effect on soil acidity, (37) 23. 



as guide to fertilizer needs, (31) 217; (35) 215. 

 by means of the plant, (32) 121. 

 clod method, (28) 717. 

 error in, (29) 316; (30) 505. 

 mechanical, (26) 219, 221; (27) U9; (28) 515, 

 620; (30) 213; (31) 418; (32) 120. 

 analysis, mechanical — 



methods, (26) 29; (28) 318; (35) 721; (36) 114, 



720; (38) 313. 

 relation to moisture equivalent, (39) 214. 

 shaker for, (32) 611. 

 value, (27) 120. 

 analysis, methods of, (27) 514, 515; (28) 111; (29) 

 308; (30) 12, 215, 624; (31) 312, 417, 514, 719. 

 806; (32) 295, 311; (33) 204, 205; (34) 806; (36) 

 204, 299, 318, 612; (39) 204. 

 antiseptics, tests, (28) 538. 

 bacteria — 



action of microorganisms on, (39) 332. 

 action of toluene and chloroform on, (36) 



815. 

 activity, (29) 20, 123, 817; (30) 217, 718; (31) 

 126. 

 bacteria, activity as affected by — 

 osmotic pressure, (40) 722. 

 plants ,(40) 299, 513. 

 various woods, (39) 325. 

 bacteria- 

 activity, relation to lime requirement, (39) 



325. 

 and fungi, ammonifying power, (32) 29. 

 fungi, associative action, (36) 215. 

 fungi, relative importance, (36) 434. 

 protozoa, relation, (36) 322. 

 soil productiveness, relation, (32) 124. 

 bacteria, as affected by- 

 acids and alkalis, (37) 213. 

 alkali salts, (26) 322; (27) 124; (28) 519, 719; 



(32) 320; (33) 323. 

 antiseptics, (31) 516. 

 arsenic, (38) 322. 

 calcium, (32) 33. 

 continuous croppings, (35) 813. 



Soil — Continued. 



bacteria, as affected by — continued, 

 crops, (37) 421. 



cyanamid and dicyanodiamid, (40) 724. 

 humus-forming materials, (37) 120. 

 irrigation, (31) 24. 

 lime, (27) 720; (30) 127. 

 limestone, (26) 428. 



magnesium and calcium salts, (38) 818. 

 manure, (26) 31; (27) 518; (32) 216; (35) 814; 



(37) 23. 

 mineral fertilizers, (31) 821. 

 phosphates and sulphates, (33) 515. 

 protozoa, (28) 330; (30) 322; (32) 321; (33) 



515; (34) 326; (36) 422, 518, 622. 

 salts, (36) 515. 

 seasons, (36) 21; (37) 421. 

 seed bed preparation, (36) 215. 

 sulphur, (30) 532. 



toluol and carbon bisulphid, (28) 824. 

 volatile conifer products, (32) 618. 

 water, (35) 814; (37) 421. 

 bacteria — 



at different depths, (36) 21. 



coli-like, studies, (38) 19. 



counting, culture media for, (32) 625. 



decomposition of silicates by, (31) 121. 



determination, (28) 727; (29) 824; (31) 731; 



(36) 31. 



distribution and activities, (27) 822. 

 bacteria, effect on— 



plant growth, (31) 827. 



rock phosphate, (35) 723. 



solubility of phosphoric acid, (36) 515. 

 bacteria — 



functions of, (31) 127. 



growth in muck, (36) 516. 



growth of, (31) 620. 



in acid soils, studies, (40) 620. 



migration of, (29) 21. 



nitrifying, effect on tricalcium phosphate, 

 (39) 23. 



nitrogen-assimilating, (39) 722. 



nitrogen-cycle, as affected by auximones, 



(37) 517. 



nitrogen fixation by, (26) 123; (28) 628; (30) 

 217. 



nitrogen-flxing, in Iowa soils, (37) 517. 



nitrogen-fixing, studies, (38) 428. 



nonsymbiotic nitrogen-fixing, (34) 813. 



notes, (31) 818; (37) 298. 



nutrition of, (35) 814. 



of frozen soils in Quebec, (40) 513. 



oxygen requirements, (37) 221. 



potash-fi.xing power, (34) 815. 

 bacteria, relation to — 



angleworms, (29) 316. 



evaporation, (27) 516. 



fertilizers, (34) 326. 



humus, (32) 721. 



hydrogen-ion exponent, (39) 723. 



irrigation, (37) 86. 



soil fertility, (34) 619; (35) 215. 

 bacteria — 



respiratory intensity, (31) 313. 



role in relation to phosphates, (40) 620. 



spore-forming, (35) 523. 



studies, (29) 221; (31) 818; (35) 626; (37) 19, 

 516, 517; (40) 739. 



toxins, (40) 23. 



vanillin-destroying, (40) 24. 



variations in, (31) 26. 

 bacteriology, (32) 216. 

 bacteriology — 



course in, (28) 332. 



digest of data, (28) 826. 



discussion, (26) 718. 



laboratory manual, (27) 728; (33) 791; (36) 

 692. 



methods in, (30) 218; (31) 420. 



notes, (27) 516. 



review of investigations, (33) 513. 



studies, (27) 517, 720; (28) 120, 121; (29) 21, 

 422; (30) 624; (31) 121; (33) 120, 823; (39) 

 324; (40) 125. 



treatise, (28) 34. 

 biology— 



and physics, ancient ideas on, (30) 212. 



field and laboratory experiments, (36) 213. 



review of investigations, (30) 119. 



studies, nitrogen determination in, (40) 711. 



