CROPPING SYSTEMS WASHINGTON, OREGON, IDAHO. 9 
ROTATION FOR INCREASING PROFITS. 
The major! ty of farmers in those sections of eastern Washington, 
eastern Oregon, and northern Idaho having an annual precipitation 
in excess of 20 inches follow a three-year rotation of wheat, oats, or 
barley, and summer fallow. Many are to be found, however, who 
have broken away from this type of farming on at least part of the 
farm and are eliminating the summer fallow on small areas by the 
use of clover in the rotation. In Nez Perce, Lewis, and Idaho 
Counties, Idaho, clover is used to quite an extent. A study of the 
cropping systems of this region shows that clover may be used with 
as much success there as in the Willamette Valley, Oreg. 
The usual method of establishing a crop rotation is to divide the 
farm into equal parts and change the crop on each field from year 
to year. For example, a three-year rotation of winter wheat, oats, 
and clover would be planned as follows : 
Table VII, — Usual form of three-field, three-year rotation of winter wheat, oats, and clover. 
Year. 
Field A. 
Field B. 
Field C 
First year 
Oats 
Winter wheat 
Clover 
Vv 
J Clover. 
Second year 
Clover 
Oats. 
Third year 
Oats 
. Winter wheat. 
On account of the hilly nature of the farm land in the section 
under discussion fields must be laid out in such a manner as to facili- 
tate the operation of farm machinery. For this reason it is not 
always easy for the farmer to divide the farm so that an equal area 
may be devoted to each crop of the rotation. The rotation may be 
carried out, however, on each field during three successive seasons. 
The crops to be grown on each field should be so selected that approxi- 
mately one-third of the farm area is devoted each year to one crop 
of the rotation. 
THREE-YEAR CROPPING SYSTEMS. 
The farmers of this section who do not wish to grow intertilled 
crops may introduce clover by using one of the following cropping 
systems : 
First year. Second year. Third year. 
Spring wheat, oats, barley, Clover for hay, seed, or pas- Spring wheat, oats, barley, 
or field peas. (The grain ture. or field peas, 
is seeded as a nurse crop 
with clover.) 
Clover is seeded with spring wheat, oats, barley, or field peas during 
the first year. In the second year the clover which was seeded the 
