COST AND UTILIZATION OF POWER ON FARMS. 
21 
practice being to pull one or more of these implements behind the 
disk. In all, 207 men did at least part of this work with tractors. 
One hundred and sixty-four of them used these implements behind 
their disk harrows, and 43 used them alone. (See fig. 6.) 
The number of men on the various-sized farms who used these 
implements and the kind of power employed are given in Table 18. 
Fig. 6.— Tractor preparing corn ground for winter wheat with a double disk and packer. 
Table 18. — Kind of power used for harroiving, rolling, planking, and packing on farms 
of different sizes. 
Size of farms (crop acres). 
Number 
of 
farmers. 
Farmers 
using 
tractors 
only. 
Farmers 
using 
tractors 
and 
horses. 
Farmers 
using 
horses 
only. 
Less than 80 
7 
28 
70 
53 
3 
11 
20 
12 
7 
7 
4 
2 
3 
14 
33 
26 
26 
19 
9 
1 
H) to 119 
3 
120 to 159. . 
17 
160 to 199 
15 
200to239.- 
47 
35 
18 
22 
14 
240 to 279 
9 
280to319 
5 
11 
9 
Total 
Per cent 
280 
100 
66 1 141 73 
24 50 1 
Here again the size of the farm had some influence on the portion 
of this work done with tractors. On 32 per cent of the farms with 
less than 160 crop acres, and on only 18 per cent of those with 160 or 
more crop acres, all this work was done with tractors. The implements 
used for this work are normally of light draft, and where the tractor 
and horses were used simultaneously for fitting the ground, the 
former was often used on the plow or disk and the latter for harrow- 
ing, etc. 
In all, 72 per cent of the harrowing, planking, rolling, and packing 
done with tractors was done with one or more of these implements 
