INDEX. 43 



Page. 



Water, factors affecting quantity used by plants 14-15, 16, 17-19, 26 



irrigation, in the semiarid region 17-18 



needs for plant growth in the semiarid region 26 



Wlieat, durum, cultivation in the semiarid region 23, 32, 33 



Kharkof , cultivation in the semiarid region 32 



macaroni. See Wheat, durum. 



spring, cultivation in the semiarid region. 31, 32 



Turkey Red, cultivation in the semiarid region 23, 32 



winter, cultivation in the semiarid region 23, 31, 32, 35, 36, 37 



Wind, effect on agriculture in the semiarid region 15-16 



Windbreaks, uses in the semiarid region 38 



Wisconsin, moisture conditions relati^"e to plant growth 14 



215 



o 



