22 BULLETIN 1202, U. S. DEPARTMENT OF AGRICULTURE. 
being kept than was needed in addition to the tractor to carry on the 
work properly and this accounts in part for the low utilization of the 
work stock. 
Taste 23.—Labor by horses owned on farms of different sizes. 
Southern area. Western area. Northern area. 
Size of farm (crop acres). 5 Horse labor. Horse labor. Horse labor. 
Num- Num- Num- 
ber of ber of ber of 
farms. Per Per | farms. Per Per | farms. Per Per 
farm. | head. farm. | head. farm’. | head. 
Hours. | Hours. Hours. | Hours. Hours. | Hours. 
Messthan 60:2. 5.0. <2 20 | 1,328 SLOT eceebesee eee leee eee 105) 977, 468 
ce ee ee a a ee 36 | 2,680 405 5 | 1,544 273 27 | 3,081 560 
VAIL OLS LOS ae tise co sericea toca 34 4,141 546 17 2, 892 373 46 3, 808 560 
37) TOYS) ae eae a a 18 | 4,952 508 18 | 3,061 440 29} 5,058 583 
MUNEONTO.  o oe os vee tt Sees oe #f 5, 945 612 19 2, 957 449 i 5, 877 575 
C2 TONGS 1 eee ee ee 5 | 6,822 749 22) 4,103 346 8 | 8,401 680 
AU RON LU! Ny ee eee IM | Mec seerrieme| [aD GLO) Lk 14 | 5,402 AGB! |e eios.dc alle noe 
POMBO OVOl. <%-..05.279 5... bool ee nee Eee eeelhe eee 12 |* 5, 753 LST sec cias oil craters oal| oe 
127 | 4,198 566 
Total and average.....| 120| 3,572 472 1 3, 767 | 398 | 
| 
Number of Farms 
50:0 25 _50 0 25 50 
800 and over... : 
f Ly: 4 
&) SOUTHERN AREA WESTERN AREA NORTHERN AREA 
Less than 200.. 
200 =399 2 
400-599.....- 
Fig. 10.—Variation in number of hours per head work stock was used 
HORSE LABOR EQUIVALENT OF TRACTOR WORK. 
Table 24 shows the horse labor equivalent of the drawbar work 
done by the average tractor in each area; that is, the number of 
hours of horse labor which would have been required to do the same 
work. For example, the average tractor in the southern area did 
110.5 acres of fall plowing durmg the year. For the fall plowing 
done with horses in this area an average of 10.1 hours of horse labor 
per acre was required, and thus the work of fall plowing done by the 
average tractor was the equivalent of 1,116 hours of horse labor in 
this area. 
Comparison of the horse labor equivalent of the total drawbar work 
done by the tractors in the different areas with the number of hours 
required by the tractors to do this work (see Table 11) shows that 
while actually in use the average tractor did the equivalent of the 
work of 8.3 head of work stock in the southern area, 9.9 head in the 
western area, 8.2 head in the northern area, and 8.7 head for all 
farms. 
The work stock on these farms were used on the average for 482 
hours per head during the year (see p. 21). Thus the average tractor 
did as much work during the year as was done by 5.5 horses (2,638 
