TILLAGE AXD ROTATION EXPERIMENTS, NORTH DAKOTA 
Xos. 10 and 12 beginning with 1915. The yields of bromegrass 
for the second and third years were 1,134 and 2.246 pounds at 
Dickinson. 664 and 1,218 pounds at Hettinger, and 580 and 650 
pounds at Williston. 
Alfalfa is sown in the spring on fall-plowed wheat stubble and 
stands two years in addition to the year of seeding. A crop is sel- 
dom obtained the first year. At Dickinson first-year alfalfa during 
16 years averaged 339 pounds: second-year, 1,749 pounds; and third- 
year, 1.804 pounds. At Hettinger alfalfa averaged 169 pounds the 
year of seeding, the second year 757 pounds, and the third year 
1,067 pounds. The lighter average yield of the second year in 
comparison with the third is largely owing to the fact that a stand 
is not always obtained the first year. In such cases the second year 
is actually a first-year crop. To this extent the average yields may 
be somewhat lighter than should be expected from an established 
sod in this district. 
The plan of rotation No. 11 was to sow red clover in the spring 
on fall-plowed wheat stubble. Eed clover, however, winterkilled 
so frequently that it was replaced by sweet clover in recent years: 
but they were dry years in which it was particularly difficult to 
obtain stands, and the results were not conclusive. 
The yields of oats, corn, wheat, and flax in rotations containing 
sod crops are assembled in Table 9. 
Table 9. — Average yields of oats, corn, wheat, and flax in sod rotations at 
Dickinson, Hettinger, and Williston, N. Dak., for the periods specified 
Station and sod crop 
Rota- 
tion 
num- 
ber 
Oats 
Corn » 
Wheat 
Flax- 
Grain 
Straw 
Grain 
Stover 
Grain 
Straw 
Grain 
Straw 
Dickinson, 1908 to 1923: 
10 
12 
Bushels 
39.4 
33.3 
Pounds 
1,648 
1,355 
Bushels 
16.5 
15.3 
Pounds 
2,581 
2,353 
Bushels 
20.6 
18.1 
Pounds 
2,316 
1,912 
Bushels 
Pounds 
Do 
7.9 
1,167 
Average .._ 
36.4 
1,501 
15.9 
2,467 
19.4 
2,114 
7.9 
1,167 
42 
11 
12 
41 
Alfalfa 
34.9 
34.3 
1,534 
1, 541 
14.0 
13.1 
2,614 
2.254 
17.9 
17.4 
1,952 
1,827 
Clover 
Hettinger, 1912 to 1922: 
24.8 
27.4 
1,583 
1,716 
6,038 
5,954 
14.9 
15.9 
2,125 
2,253 
5.3 
1,154 
Do 
Average __. .. 
26.1 
1,650 
5,996 
15.4 
2,189 
5.3 
1,154 
42 
11 
10 
12 
Alfalfa 
28.4 
22.4 
1,916 ' 
1,523 
5,164 
6,586 
20.2 
14.4 
2,991 
2,371 
Clover .. 
Williston, 1910 to 1920: 
29.3 
22.1 
1,591 
1,035 
11.1 
11.3 
2,894 
2,889 
13.8 
14.7 
1,360 
1,224 
Do 
4.4 
500 
Average 
25.7 
1,313 
11.2 
2,892 
14.3 
1,292 
4.4 
500 
1 Yields of corn at Hettinger are total wet weights as harvested for silage. 
At Dickinson oats on fall-plowed bromegrass sod in rotation 
No. 10 averaged 39.4 bushels. This rotation is favored to some ex- 
tent by its location, and the yields of all grain crops are higher in 
it than in rotation Xo. 12. In rotation Xo. 12 flax follows the 
bromegrass, and the oats are on fall-plowed flax stubble. Oats 
in this rotation averaged 33.3 bushels, or 6.1 bushels less than in 
rotation Xo. 10. The average of the oats in the two rotations was 
36.4 bushels. Two plats of oats on fall-plowed wheat stubble in 
