270 DRY-FARMING 
soil containing 70 per cent of water, it was only 5.2 
per cent. Carleton, in a study of analyses of the 
Fig. 64. Dry-farm Brome-grass. Montana, 1908. Yield, 1.4 tons per acre, 
same varieties of wheat grown in humid and semi- 
arid districts of the United States, found that the 
percentage of protein in wheat from the semiarid 
area was 14.4 per cent as against 11.94 per cent in the 
