ROTATION AND CULTURAL METHODS AT EDGELEY, N. DAK. 13 
of a bushel more than on the corn ground. There is some evidence 
of a carry-over effect of the fallow, as the oats following wheat in 
the fallow rotation have outyielded the oats in the corn rotation in 8 
of the 13 years. The average increase for the 13 years is 5 bushels per 
acre of grain and nearly 200 pounds of straw. The average yield 
of corn, which occupies in rotation No. 3 the place of the bare fallow 
in rotation No. 8, has been 6.4 bushels of grain and 3,432 pounds 
of stover per acre. 
Rotation No. 8 is fallow, oats, and wheat, and rotation No. 4 is 
corn, oats, and wheat. The heavier yield of oats has been on fallow 
eight years, and on corn five years. The 13-year average increase on 
fallow has been 4.2 bushels of grain, but less than 100 pounds of 
straw per acre. There apparently has been in this case no carry- 
over effect of the fallow, as the yield of wheat in these rotations 
differs only by one-tenth of a bushel. 
The yield of corn has averaged 6.3 bushels of grain and 3,344 
pounds of stover, being practically the same as in rotation No. 3. 
In the same four rotations on section 9 for the three years, 1917 to 
1919, inclusive, the wheat on fallow has outyielded that on corn 
ground each year, the average increase being 1.9 bushels. No carry- 
over effect has been apparent, however, as the average yield of the 
oats following wheat is a fraction of a bushel less in the fallow than 
it is in the corn rotation. The oats on fallow have outyielded the 
oats on corn ground each year, the average increase being 14.3 
bushels. The wheat following the oats on fallow yielded 1.1 bushels 
more than the wheat on oats following corn. 
Summing up the evidence from the four rotations on both the main 
field and section 9, it appears that in a comparison of fallow and 
corn ground there has been a small advantage in favor of the fallow. 
The response of oats to the fallow is apparently somewhat greater 
than that of wheat. Whatever advantage there may be from the fal- 
low is practically exhausted by the first crop. There is some tend- 
ency to show a small carry-over effect of fallow on the second crop, 
but it is so small that the evidence is not very clear. It would appear 
from the direct comparison of these rotations that the difference in 
yielding power between fallow and corn ground is so small that a 
choice between them is really to be determined by the choice between 
either conducting a bare fallow or raising a crop of corn averaging 
for 13 years about 6-J bushels of grain and more than L| tons of stover 
per acre. 
Two other rotations in the main field for the period from 1908 to 
1919 and in section 9 from 1917 to 1919 bear evidence on this subject 
and lead to the same conclusions. Rotation No. 18 is corn on spring 
plowing, oats on disked corn ground, fallow, and wheat on fallow. 
Rotation No. 19 is the same, but with the wheat on disked corn ground 
and the oats on fallow. 
In the main field the average yield for 12 years of oats on fallow 
has been 6.1 bushels more than on disked corn ground, but the yield 
