INDEX. 



A. 



PAOB 



Absorption and movements of water in soils 221 



of solids from solutions 267 



of gases by soils 272, 275 



Acacias, tolerance of alkali 480 



Accessory minerals 50 



Acid, strength used in soil analysis 341 



Acidic and basic eruptive and metamorphic rocks 49 



Acidity, neutrality, alkalinity of soils 322 



Acids of different strengths, analysis with ; table 326, 341 



Action of plants in soil formation, mechanical and chemical 19 



Aeration and reduction as influencing nitrification 147 



effects of insufficient, in soils 2.So 



excessive, injury in arid regions 2 So 



^robic and anerobic bacteria 144 



Air, functions in soils 279 



" of soils, composition of 2 So 



Air-space in soils ; figure 108 



Alabama, vegetation and soil-characters 511 



Alaska current, effects on California climate 296 



Alinit 149 



Alkali carbonates and snlfates, inverse ratio J5I, 452 



carbonates, effects on clay 62 



effects on culture- plants ; figure 426, 427 



Alkali-heath, range, tolerance of alkali, figure 544, 545 



Alkali lands, crops for strong jf>S 



effects of irrigation on jrS 



efficacy of shading 157 



exceptionally productive when reclaimed jS^ 



fertilization not needed in }S^ 



formation from leachings of slopes 15,; 



geographical distribution of 423 



high and lasting production when reclaimed }Sj 



inducements toward reclamation of 4Si 



in the San Joaquin valley, Cal., figure , 425 



possible injury to, from excessive leaching 462 



565 



