32 BULLETIN 757, U. S. DEPARTMENT OF AGRICULTURE. 
Ground previously planted to potatoes, corn, or flax appears to 
give best returns if grain is sown without previous plowing for the 
crop. 
In general, it would seem that the practice of stubbling-in is not 
to be advocated except possibly in the case of winter rye. Many 
farmers in the eastern part of the State believe that stubbling-in rye 
is entirely justified. 
ROTATION. 
Hitherto very little consideration has been given to the subject of 
crop rotations by the farmers of North Dakota. Of 40 farmers 
interviewed on this subject, only 12 gave any information as to 
order of planting crops, the greater number stating that they gave 
little or no attention to the matter. A few said that they changed 
from one crop to another as often as possible. Only seven farmers, 
and these in widely separated counties, were found who followed a 
fairly uniform system of rotation. These men adhered as closely 
as possible to this order: Barley, 1 year; wheat, 1 year; oats, 1 year; 
summer fallow or intertilled crops, 1 year. 
The greatest difficulty in establishing a system of rotation is the 
fact that the type of farm is based on a one-crop system, wheat, pro- 
duction occupying such a large part of the farm area. However, 
the increase of stock production is materially remedying the situa- 
tion, and tame hay and other feed crops are occupying larger and 
larger percentages of farm areas. Alfalfa, timothy, and clover, and 
corn are now of some importance, though 10 years ago these crops 
were scarcely known in the State. 
Thus far no serious decrease in yields, due to depletion of the soil, 
has been noted in North Dakota. New land, that is, land that has 
never produced anything but prarie grass, is being brought into cul- 
tivation every year in all parts of the State, with the possible ex- 
ception of some of the Red River Valley counties. As long as this 
condition prevails and wheat occupies so large a proportion of the 
crop land, rotations will hardly be given serious consideration by 
the farmers. 
MANURE. 
A decade ago scarcely any manure was applied to the land, because 
there was little to apply. Practically the only stock on the farms 
were work animals. At present, however, from 5 to 50 animal 
units? of productive stock or even more, besides the work animals, 
are found on every farm, so that the amount of manure now pro- 
duced annually is worthy of consideration. In general, on the aver- 
age farm of 640 acres, manure is applied to 30 acres or more every 
1 An animal unit is a mature horse or cow or as many smaller animals as require the 
feed of a horse or cow, approximately 2 young cattle, 5 hogs, 7 sheep, or 100 hens. 
