6 BULLETIN 625, U. S. DEPARTMENT OF AGRICULTURE. 
The groups of farms which devoted less than 20 per cent of their 
field-crop area to clover made an average of $171 after deducting 
6 per cent interest on capital invested, and the group which devoted 
more than 20 per cent of their field-crop area to clover made an aver- 
age of $560 each. The increase in profits was due (1) to the increase 
in yields and (2) to the profitableness of clover-seed production in 
comparison with other farm crops for the year in which these records 
were taken (1912). It will also be seen from the interest made on 
investment that those farms devoting more than 20 per cent of their 
field crop area to clover used the capital invested in land and equip- 
ment 54.2 per cent more efficiently than the farms growing no clover. 
The beneficial effect of clover in the rotation is quite generally 
recognized among the farmers of the moister sections of eastern 
Washington, eastern Oregon, and northern Idaho. The importance 
of this crop, however, as a means of maintaining a profitable system 
of farming and of improving the soil fertility is very much under- 
estimated. The roots and stubble of a good clover crop are said to 
contain fertilizing elements equivalent per acre to from 3 to 5 tons of 
barnyard manure. Its value to the soil in supplying organic matter 
and thus improving the physical condition can not be estimated. A 
study of Tables III, IV, and V should convince the most skeptical 
farmers that clover is one of the biggest factors in building up a 
profitable farm business. The maintenance of soil fertility in the 
section above described is as much dependent on legumes, especially 
clover, as are the silt loam soil farms in the Willamette Valley, Oreg. 
A recent stud} 7 by the author of a few farms in different parts of this 
region on which clover is being used in the rotation showed that they 
were returning from 15 to 25 per cent larger yields than farms not 
growing this crop. 
SEEDING CLOVER WITH A NURSE CROP. 
The small acreage devoted to clover in the moister section of 
eastern Washington, eastern Oregon, and northern Idaho is due in 
large measure to the prevailing idea that in order to secure a stand 
this crop must be seeded alone. The labor of preparing the soil and 
of seeding the crop by this method is practically the same as for small 
grain. The use of the land is also lost for one year except for the 
small amount of pasture that can sometimes be obtained. A few 
farmers in different localities, however, have broken away from 
this practice and are seeding clover with a grain crop. This method 
of seeding requires but little more labor than is necessary for seeding 
grain alone, and the nurse crop returns a profit while the clover is 
becoming established. The methods used by a number of farmers 
and their success in seeding clover with a nurse crop was studied 
during the past four years with the view of determining the feasi- 
bilitj' of this method of seeding in this region. 
