ROTATIONS AND SOIL FERTILITY 299 
Rosen states that rotation is very commonly prac- 
ticed in the dry sections of southern Russia, usually 
including an occasional summer fallow. As a type 
of an eight-year rotation practiced at the Poltava 
Fig. 71. Dry-farm corn. Rosebud Co., Montana, 1909. Cut for for- 
age. Yield, 9.4 tons well-cured fodder. 
Station, the following is given: (1) Summer tilled 
and manured; (2) winter wheat; (3) hoed crop; 
(4) spring wheat; (5) summer fallow; (6) winter 
rye; (7) buckwheat or an annual legume; (8) oats. 
This rotation, it may be observed, includes the grain 
crop, hoed crop, legume, and fallow every four years. 
As has been stated elsewhere, any rotation in dry- 
farming which does not include the summer fallow 
