10 BULLETIN 625, U. S. DEPARTMENT OF AGRICULTURE. 
previous season is used for hay, seed, or pasture, on ground which 
will be planted to spring crops the following year. The third year of 
the rotation is devoted to the growing of winter wheat, spring wheat, 
oats, or barley. Winter wheat, as already stated, is usually seeded 
on land which grew clover until about May 1 and was then sunnner- 
f allowed, although spring crops may be used. Spring wheat, oats, 
barley, or field peas give best results on ground from which the clover 
was used for hay, seed, or pasture. 
Farmers who wish to grow intertilled crops instead of summer 
f allowing their land may use one of the following systems : 
First year. Second year. Third year. 
Corn, beans, potatoes, or Winter wheat, spring Clover for hay, seed, or 
field peas planted in rows wheat, oats, barley, or pasture, 
and intertilled, field peas. (Grain is 
seeded as a nurse crop 
with clover.) 
The first year of these cropping systems is devoted to the growing 
of corn, beans, potatoes, or field peas planted in rows and inter- 
tilled. In those sections where the climatic conditions are unfavor- 
able for growing corn or beans the farmers must depend on potatoes 
or field peas for an intertilled crop. During the second year of this 
cropping system the ground from which the crop can be harvested 
in time for fall seeding may be used for winter wheat. The pea 
and bean crops may always be harvested in time to permit fall 
seeding, but unless the corn crop is cut for ensilage or for fodder and 
hauled from the field, spring grain must be sown. Winter grain is 
sometimes seeded, however, in the standing corn with a one-horse, 
five-hoe grain drill, and the corn crop husked from the standing stalk 
in the usual manner. As a rule, potatoes may be dug early enough 
to permit fall seeding unless they are very late in maturing. Spring 
wheat, oats, barley, or field peas all do exceptionally weU on land 
which was devoted to intertilled crops the previous season. In 
using any of the above crops it must be remembered that they are 
to be sown as a nurse crop with clover. The third year of the rota- 
tion the clover is used for hay, seed, or pasture. It is very important 
that clover land be plowed in the fall when possible to do so. 
FOUR-YEAR CROPPING SYSTEMS. 
Many farmers in the above-described territory wish to summer 
fallow or grow a cultivated crop on the land once in four years. In 
