38 
BULLETIN 174, U. S. DEPARTMENT OF AGRICULTURE. 
is less than two years, which shows that for the most part they are 
very modern outfits. The tractor did not entirely displace the horses 
on any farm. 
Table XXII. — Displacement of horses by tractors on farms. 
Item of comparison. 
Farms on which 
horses were — 
Dis- Not dis- 
placed, placed. 
Vll farms 
acres. . 
do.... 
Number of farms 
Average size of farm 
Average area tilled p?r farm 
Average number of horses per farm: 
Before purchase of tractor 
After purchase of tractor 
Average number of horses displaced per farm 
Value of horses displaced per farm dollars- 
Average value per horse do. . . 
Average drawbar rating per farm horsepower. 
Average cost of tractor dollars. 
Total present rating per farm horsepower. 
Average area tilled per drawbar horsepower of tractor acres. 
Average area tilled per horse: 
Before purchase of tractor do. . . 
After purchase of tractor do... 
Average area tilled per total horsepower after purchase of tractor. . .do. . . 
Average age of tractors years. 
Average use of tractor per year days. 
Cost of maintaining a horse per year (estimated) dollars. 
Average price of fuel per gallon do. . . 
Average price of oil per gallon do... 
39 
924 
844 
25.3 
8.8 
10.5 
,115.86 
188. 84 
26.1 
,635.00 
34.9 
32.3 
33.4 
95.9 
24.2 
1.8 
94.5 
84. 09 
.147 
.423 
43 
875 
661 
13.2 
13.2 
176.10 
24.3 
,775.00 
37.5 
27.2 
50.0 
50.0 
17.7 
1.9 
120.2 
105.56 
.185 
.388 
82 
896 
748 
18.9 
11.1 
7.8 
,423.89 
182.55 
25.1 
702. 00 
36.2 
29.8 
39.5 
67.3 
20.5 
1.9 
101.6 
96. 81 
.167 
.405 
While the value of special equipment which would be required with 
the tractor is not shown here, from previous tables it is evident that the 
value of such equipment would not be less than $700 per farm; there- 
fore, en more than 50 per cent of the included farms the purchase 
of the tractor increased the invested capital approximately $3,500 
and on the remainder the horses displaced would lack about $300 of 
equaling the value of the tractor and its necessary equipment. 
On the farms where horses were displaced, the tilled acreage per 
horse before the purchase of a tractor was 33.5, which is believed to be 
about the normal area. Although the acreage per drawbar horse- 
power of the tractor on these farms was only 32.3, yet an average of 
8.7 horses per farm was retained, making the tilled acreage per unit 
of power 24.2 acres. On the other hand, the tilled acreage per horse 
on the farms where horses were not displaced was 50 acres, and the 
tilled acreage per drawbar horsepower of the tractor purchased was 
27.2 acres, or an average of 17.7 tilled acres per unit of total horse- 
power. The tilled acreage per total horsepower for both of these 
groups would appear to be too small for the most economical 
operation. 
In Table XXIII are shown some further data relative to the dis- 
placement of horses by tractors. This table was prepared from 
figures furnished by tractor owners in North Dakota who had used 
their tractors for two seasons. 
