INDEX 



491 



Oats, yield due to rainfall, 234. 



under irrigation, 253. 



duty of water for, 253. 



early yield, 457. 

 Ocean water, 91. 



composition, 92. 



Office of Experiment Stations, 464. 

 Olin, 484, 285. 



Olive, duty of water for, 322. 

 Omaha, 408. 

 Onions under irrigation, 310. 



in humid climates, 410. 

 Orange, 314. 



spacing, 317. 

 Orchard. See also Fruit-growing. 



time of fall irrigation, 177. 



time to irrigate, 187. 



furrowing, 210. 



under irrigation, 314. 



method of irrigation, 315. 



care of young, 315. 



furrows for young trees, 317. 



time of irrigation, 319. 



effect of irrigation on buds, 320. 



quantity of water for, 322. 



danger of over-irrigation, 323. 



inter-culture, 323. 



growth without irrigation, 324. 



duty of water in Africa, 339. 

 Orchard-grass, 278. 

 Organization, for distribution, 365. 

 Ornamental Plants under irrigation 



328. 



Oshkosb, Wis., 407. 

 Overfalls, 351. 



Over-irrigation, 371. See also Seepage, 

 Alkali. 



delays ripening, 251. 



danger in orchards, 323. 



water-loss from, 373. 



Packard, 312, 329. 



Packing, natural, of soil, 70. 



Paddock, 329. 



Palestine, 446. 



Palmer, 224. 



Pastures under irrigation, 281. 



Patten, 71, 106. 



Peach, protein in, 221. 



sugar in, 225. 



spacing, 317. 

 Peanuts, 310. 

 Pears, protein in, 221. 



spacing, 317. 



duty of water for, 322. 

 Peas, protein in, 221. 



under irrigation, 301. 



Pecos River, 96. 

 Pennsylvania, 409. 



Permanence of irrigation agriculture, 

 472. 



of irrigation assured by history, 474. 

 Persia, 446. 

 Peru, 447. 



duty of water in, 342. 

 Peterson, 390. 

 Phelps, 411, 418. 

 Phoenix, 408. 

 Pinckney, 403. 

 Plant. See also Crop. 



use of soil moisture by, 108. 



absorption of water by plant-roots, 



. 109. 



initial percentage and water use, 111. 



effect of water distribution on water 

 use, 114. 



effect of time on water-use, 115. 



effect of soil depth on water use, 116. 



effect of soil composition on water 

 use, 117, 118. 



effect of, on water use, 120. 



rigor of, and water use, 121. 



effect of cultivation on water use, 121. 



effect of age on water use, 122. 



effect of roots on water use, 122. 



effect of kind on water use, 123. 



effect of seasons on water use, 123. 



water-cost of dry matter, 127. 



carbon assimilation, 128. 



age of, and carbon assimilation, 129. 



conditions of growth, 130. 



water-cost of several plants in differ- 

 ent countries, 133, 134. 



range of water-cost, 134. 



effect of soil on water-cost, 137. 



effect of plant-food on water cost, 139. 



effect of cultural operations on water- 

 cost, 141. 



vigor of, and water-cost, 143. 



water-cost and varying quantities 

 of water, 144. 



nature of, and water-cost, 154. 



development under irrigation, 158. 



response to irrigation, 159. 



proportion of roots, 160. 



proportion of leaves and stems, 163. 



proportion of heads and grain, 166. 



proportion of parts, 169. 



composition, 216. 



water in, 217. 



constituents, 217. 



ash constituents in, 219. 



protein in various, 220, 



fat in, 223. 



