10 
BULLETIX 705, U. S. DEPARTMENT OF AGRICULTURE. 
From Table IV it will be seen that farm income was 6.6 per cent of 
the capital invested in the group of clay farms having an income of 
$77 per productive animal unit as compared with 2.87 per cent in 
the group of farms having but $29 income per productive animal 
unit. Likewise the group of silt loam farms having an average 
income of $82 per productive animal unit made 8.92 per cent as 
compared with 4.41 per cent for the group having but $29 income 
per productive animal unit. Evidently, farm efficiency on both the 
clay and silt loam soils was greater where the income per productive 
animal unit was greater. 
Securing a high income per productive animal unit in the main 
involves (1) the use of farm animals as scavengers to consume all 
feed that would otherwise go to waste; (2) economical and efficient 
feeding; (3) the breeding up of animals which will sell well and use 
feed economically; and (4) the use of good business judgment in 
marketing. 
The variation in the percentage farm income is of capital in the 
different groups of farms in Table IV was partly due to a variation 
in crop yields, for it will be seen that the groups of farms having the 
highest income per productive animal unit also had the highest crop in- 
dex. Especially is this true with the groups of silt loam farms where the 
crop index varies from 89 in the group of farms receiving $29 per 
productive animal unit to 110 in the group receiving $82 per pro- 
ductive animal unit. On the clay soil the influence of crop yields 
was not so prominent, since the variation in crop index only ranged 
from 96 in the group of farms receiving $29 per productive animal 
unit to 102 in the group receiving $77 per productive animal unit. 
CROP YIELDS. 
In Table V the farms are divided into groups according to crop 
index. The crop index of the clay farms is based entirely upon the 
68 clay farm records. Likewise, the crop index of the silt loam 
farms is based only upon the 144 silt loam farm records. 
Table V. — Relation of crop yields to percentage farm income is of capital on 212 farms 
in Marion and Polk Counties, Oreg. {1912). 
Salem clay. 
Silt loam. 
Item. 
Crop 
index 91 
and less. 
Crop 
index 92 
to 106. 
Crop 
index 107 
and over. 
Crop 
index 89 
and less. 
Crop 
index 90 
to 109. 
Crop 
index 110 
and over. 
23 
79 
S40 
824.764 
S653 
2.64 
23 
99 
S55 
S22.021 
S1,0S5 
4.93 
22 
118 
S59 
$28,472 
SI, 596 
5.61 
43 
76 
S43 
S21,630 
$746 
3.44 
50 
101 
S55 
S21,798 
81,485 
6.81 
51 
124 
Income per productive animal unit 
, 866 
820,975 
81,940 
Percentage farm income is of capital 
9.25 
