SPRING WHEAT IN THE GREAT PLAINS AREA. 19 
small grains, the yields have been comparatively low, regardless 
of preparation. 
As between oats and wheat, whether spring or fall plowed, or 
between spring or fall plowing of either wheat or oat stubble, no 
decision is apparently to be made from the data at hand. The 
advantage, if any, seems to be in favor of fall-plowed oat stubble. 
The highest average yield, and it is a very high average, 27.5 
bushels per acre, has been obtained by summer tillage. But spring- 
plowed corn ground has averaged 26.1 bushels; fall-plowed corn 
ground, 24.1 bushels; and nine plats of disked corn ground, well 
distributed over the field, have averaged 23.3 bushels per acre. 
Considering the importance of corn in a general farming system 
and the small advantage shown by summer tillage over corn land in 
producing wheat, it would seem that even here where summer tillage 
has been productive of such high yields, it can have no regular place 
in a permanent farming system. 
The use of manure on corn does not appear to have had as yet 
any appreciable effect upon the wheat that followed the corn. 
The use of winter rye plowed under as green manure has thus 
far been productive of considerably better results than the similar 
use of either peas or sweet clover. This difference in yield is probably 
due to the fact that winter rye may be plowed under considerably 
earlier than either the peas or sweet clover. 
Both high yield and low cost of production have combined to 
give the greatest profit per acre, $11.56, from wheat on disked corn 
ground. The high yield of wheat on summer tillage has been scarcely 
sufficient to overcome the increased cost of this method. t It shows 
a profit of $7.75 per acre, while spring-plowed land that had been 
cropped shows a profit of $7.77 per acre, and fall-plowed land shows 
$7.51. While green manuring shows about the same production as 
land from which a crop was removed, the high cost of the method has 
reduced the profit from it to 93 cents per acre. 
EDGELEY FIELD STATION. 
The field station at Edgeley, N. Dak., is located on a soil that is 
derived from the decomposition of shale. Shale in undecomposed 
particles is found very near the surface. In the third foot the shale, 
while broken and offering fairly free passage to water, is not as yet 
broken down into soil. The depth of feeding of crops is practically 
limited to the first 2 feet. The first foot carries an exceptionally 
large proportion of water available to the crop. The limited depth of 
soil that functions in the storage of water and in the development 
of the crop, however, limits the supply of water that can be carried 
in the soil to about half of that carried by soils of greater depths. 
This makes the crop peculiarly dependent upon rains that fall while 
it is growing. 
