22 BULLET IX 1293, U. S. DEPARTMENT OF AGRICULTURE 
Disked potato ground was as good as corn ground and almost as 
good as fallow as a preparation for small grains. 
Manure applied to fallow before plowing in the spring of the 
fallow year did not increase grain yields during the 11 years of the 
experiment at Hettinger. There Avas a tendency in wet years toward 
an increase and in dry years toward a decrease in the yield of wheat 
and oats. There was no increase in the weight of corn silage the 
second year after manure. In a single three-year rotation at Dickin- 
son manure applied before corn increased the yield of fodder about 
25 per cent, but it did not increase either the Avheat or the oats in the 
second and the third years of the rotation. 
Seeding wheat on disked wheat stubble can not be condemned on 
the basis of these experiments. The yields on both first-year and 
second-year disking exceeded those on fall plowing during a six- 
year test at Hettinger. Sowing wheat on disked stubble frequently 
reduces yields through an increase of weeds and the resulting loss of 
moisture. 
Plowing under green-manure crops did not result in an increase in 
the yields of grain crops immediately following or of other crops 
in the rotations over those in similar rotations containing fallow 
instead of green manure. While the method of handling the green 
manure makes the results more comparable with fallow than with 
other methods, the yields have been slightly less and the expense 
greater by the cost of seed and seeding. There seems to be no cumu- 
lative effect from the green manure, and a legume is of no more 
value than a nonlegume. 
Bromegrass and alfalfa are recognized as the most productive 
perennial hay plants available for the area, but are of doubtful 
utility in short rotations. No measurable benefit to succeeding grain 
yields can be noted as an effect of sod. Difficulty in securing stands 
under the conditions of the experiments reduced the yields of hay 
below a profitable point for the period the land was occupied. 
Where a stand is established it should be allowed to remain for 
several years rather than plowed up with the hope of benefiting suc- 
ceeding grain crops. 
Continuous cropping to wheat, oats, and barley on spring plowing 
and on fall plowing resulted in marked reductions in the yields of 
those crops. This reduction appears to be the result of weeds rather 
than of a decrease in the fertility of the soil. Continuous cropping 
to corn increased the yield of mature grain and of fodder at Wil- 
liston and of silage at Hettinger, but it slightly decreased the quan- 
tity of fodder at Dickinson. 
