348 THE SMALL GRAINS 



more, South Dakota, substation in the very dry year 1904. 

 Four wheats, 1 emmer, 2 oat varieties, and 2 barleys 

 were sown in tenth-acre strips directly across 3 pieces 

 of land, separated only by roads, one of which pieces 

 had been in wheat, one in corn, and one in fallow 

 the year before. All plats yielded from nothing to 3.3 

 bushels to the acre on the wheat ground. On fallow 

 they yielded from 8.3 bushels to 54.4 bushels, and after 

 corn from 11.8 bushels to 48.1 bushels to the acre. All 

 except the 2 oat varieties yielded considerably better 

 after corn than on fallow, and from 1 1 to 50 times as much 

 as after wheat (Cole, 1906, pp. 56-59). 



Corn appears to be the best general 'crop for preceding 

 a small cereal in the rotation, but it will not do well in 

 all parts of the Great Plains. In the extreme northern 

 portion, field peas may precede the cereal, or potatoes, 

 where practicable from other standpoints. If field peas 

 are used, humus will also be added to the soil. In the 

 southern and extreme western portions, where the drought 

 is too severe for corn, the sorghums or cowpeas may be 

 used, the latter serving also as a green-manure. Well 

 adapted cultivated crops are yet needed in this area, 

 though even in North Dakota corn is demonstrated to 

 be superior as a forage to the hay crops. In 6 to 8 years' 

 experiments at Edgeley, Dickinson, Williston, and Het- 

 tinger, corn furnished an average weight of forage from 

 3760 to 7657 pounds, brome-grass the next highest from 

 810 to 2670 pounds, alfalfa from 1950 to 2040 pounds, 

 and clover from 625 to 1660 pounds (Thysell, McKinstry, 

 Towle, and Ogaard, 1915, pp. 179-180). 



375. A winter wheat following corn must often replace 

 a spring cereal in the middle Great Plains, which, how- 

 ever, is not a difficult arrangement. Where oats follows 



