14 BULLETIN 705 ; U. S. DEPARTMENT OF AGRICULTURE. 
It will be seen that the average yield of wheat on the clay farms 
was 526 pounds per acre greater than the yield of oats; also that the 
wheat crop was worth SS.90 per acre more than the oat crop. Differ- 
ently stated, the wheat crop was worth 1.68 times as much per acre 
as the oat crop. On the silt loam farms, according to Table X, the 
yield of oats per acre was 114 pounds and 551 pounds, respectively, 
below the yield of wheat and barley. Likewise, the cash value of 
the oat crop per acre was $3.18 and $6.01, respectively, below the 
value of the wheat and barley crops. 
If Tables IX and X represent even approximately the comparative 
values and yields per acre of oats, wheat, barley, and corn, the profit- 
ableness of general farming in the Willamette Valley may be increased 
greatly by a readjustment of the acreage devoted to these crops. 
Since oats occupied 43 per cent and wheat but 19.8 per cent of the 
rotation area on the clay farms, it would appear from a study of 
Table X that oats should largely be replaced by wheat or some other 
more profitable crop. It should be remembered, however, that most 
of the wheat crop of the clay farms was grown upon land that had 
been summer fallowed the previous year, while little or none of the 
oat crop was grown on summer-fallowed land. 
On the silt loam farms studied in 1912 oats occupied 38.8 per cent 
of the rotation area. This was nearly twice the area occupied by any 
other crop. A study of Tables IX and X seems to indicate also that 
much of the oat crop on the silt loam farms can be replaced profitably 
by other crops. While Table IX shows that corn is the most profit- 
able of the cereal crops, the moist fall and winter climatic conditions 
of the Willamette Valley practically limit its production to what can 
be used on the farm. Owing to its superior yield corn should be 
grown much more extensively, especially for silage and fall and early 
winter feeding. It will be claimed by some that much of the oat 
crop is produced on land that will not raise good b parley. While there 
may be some merit to this claim, most Willamette Valley soils pro- 
duce good yields of barley. Since barley is the equal of oats, pound 
for pound, as a general stock feed, and since our present knowledge 
indicates that there is a marked difference in the yield of the two 
crops, it appears that the acreage of oats should be cut down and that 
barley should be grown more extensively. 
SOME FACTORS WHICH INFLUENCE CROP YIELDS. 
Table V shows that the percentage farm income of capital was 
highest in the group of farms having the highest average crop yields. 
Any means whereby crop yields may be increased, therefore, should 
be highly important. The following discussion deals with a few of 
the more practical ways of increasing crop yields. 
