Index 



501 



Time as a unit for division of water, 

 242. 



Transpiration, greatest during sun- 

 shine, 45, 46 ; need of water, 50 ; 

 mechanism, 46; method, 46 ; control' 

 53. 



Tulare Exp. Station, 276. 



Tull, Jethro, system of intertillage,157. 



Turbine wheel, 308. 



Underdraining, practical details, 467 ; 

 cost, 489; peat lands, 491. 



Underflow, intercepting, 459. 

 Underground water, diverting for irri- 

 gation, 304. 

 Units of water measurement, 239. 



Vegetables, garden irrigation, 385. 

 Ventilation of soil, 419. See soil venti- 

 lation. 

 Vir weir, 78. 

 Vosges, water-meadows, 219. 



Warping, 94, 261. 



Washing of soil, principles governing, 

 337. 



Washington, dry farming, 100; rainfall, 

 101, 204. 



Water, apparent greater service in arid 

 climates, 5, 104; need for nitrifica- 

 tion, 12; fertilizing value, 14, 93, 251' 

 259; only one of the necessary plant" 

 foods, 15; amount used by crops, 16 

 21, 24, 30, 36, 37, 38, 39, 41, 46, 60, 97, 122, 

 160, 174, 177, 215; variations in amount 

 used by crops, 39; used in transpira- 

 tion, 50; action in plant feeding, 58; 

 amount needed for given crop, 87; 

 least amount for paying crop, 95 ; least 

 amount in soil which permits growth, 

 111, 225; retained by sand, 114, 224; 

 insufficiency for irrigation, 117; in 

 subsoiled ground, 136; lost through 

 mulches, 142, 201 ; lost from wet soil, 

 148; in fallow ground, 155, 225; capil- 

 lary spreading, 161, 330, 377; conserved 



by tillage, 164, 353 ; importance of 

 amount and distribution in potato 

 culture, 172; duty, 196 (see Duty of 

 water) ; amount for single irrigation, 

 222, 223, 225, 227, 234 ; capacity of soils, 

 224, 353; best amount for crops, 227; 

 measurement, 239; cold, for irriga- 

 tion, 249; value of turbid, for irriga- 

 tion, 259; alkali waters, 267, 268, 284, 

 285, 287; -supplying, for irrigation, 290; 

 methods of applying, 329; loss by per- 

 colation, 330; rate of application, 331, 

 332, 337; depth in flooding, 346; 

 amount needed for lawns and parks, 

 392 ; amount needed for sub-irriga- 

 tion, 397, 401. 



Water level, 416. 



Water-logged soil, 11, 334. 



Water-meadows, 16, 92, 219, 251, 359 ; 

 English, 76, 360; use of sewage, 220, 

 254, 403, 409 ; frequency of irrigation, 

 237; Belgian, 362; Italian, 362; moun- 

 tain, 74, 365. 



Water supply, for irrigation wells, 78, 

 84, 85, 86, 251, 393 ; from rivers, 290; 

 underground waters, 304; lifting by 

 water-power, 306; storm water, 311; 

 by wind power, 312; by engines, 324, 

 326; cost, 324; by animal power, 325, 

 328; for cranberries, 367. 



Water wheels, 75, 306, 308. 



Weiss, number of breathing pores, 51. 



Wells, for irrigation, 78, 84, 251, 393; in 

 Algeria, 85; in Hawaii, 86; for lawns 

 and gardens, 393. 



Wheat, ratio of grain to straw, 96; 

 water used, 97, 101, 215; intertillage, 

 158; frequency of irrigation, 235. 



Willcocks, W., Egyptian irrigation, 84, 

 211 ; cost of pumping, 326. 



Wilson, H. M., area of land irrigated, 

 88; duty of water, 211; lifting water, 

 309, 311, 325, 327. 



Winds, lessening destructive effects, 

 168. 



Windbreaks, 169. 



