UNITED STATES DEPARTMENT OF AGRICULTURE 
BULLETIN No. 997 
yJw Joint Contribution from the Office of Farm Management and ♦« 
4? Farm Economics, H. C. TAYLOR, Chief; Bureau of Public S 
^ZXT^ru 
Roads, THOS. H. MacDONALD, Chief; and Bureau o f 
Animal Industry, JOHN R. MOHLER, Chief. 
Washington, D. C. 
December 21, 1921 
THE COST AND UTILIZATION OF POWER ON FARMS 
WHERE TRACTORS ARE OWNED. 
286 Farms— Ohio, Indiana, Illinois— 1920. 
By H. R. Tolley, Agricultural Engineer, and L. A. Rbynoldson, Junior Farm 
Economist. 
CONTENTS. 
Introduction 1 
Summary 2 
Areas in which investigation was made 5 
Size and age of tractors 9 
Workstock 10 
Size of farm 11 
Size of farm and size of tractor 12 
Workstock on farms of different sizes 12 
Work done by tractors 13 
Drawbar work 15 
Belt work 24 
Custom work 25 
Work done by horses 26 
Horse labor equivalent of tractor work 34 
Proportion of work done by horses and by 
tractors 35 
Number of workstock used on different opera- 
tions 37 
Cost of keeping work stock 39 
Cost of using tractors 45 
Reliability of tractors 53 
Cost of power for different operations as fur- 
nished by horses and by tractors 54 
Annual cost of power for drawbar work 54 
Changes in size of farm and number of work- 
stock after purchase of tractors 56 
Increase in investment due to purchase of 
tractors 59 
| Saving of man labor due to use of tractors 60 
INTRODUCTION. 
During October and November of 1920 the Bureau of Animal 
Industry, the Office of Farm Management and Farm Economics, 
and the Bureau of Public Roads of the United States Department 
of Agriculture made an investigation of the cost and utilization of 
power on representative farms where tractors are owned in Ohio, 
Indiana, and Illinois. Two hundred and eighty-six farmers in these 
States who had been using tractors for a year or more were inter- 
Note.— Special credit is due to W. R. Humphries, Bureau of Public Roads, for valuable assistance in 
collecting and in supervising the tabulation of the data presented in this bulletin. 
Acknowledgement is also due to O. A. Juve, Office of Farm Management and Farm Economics, M. A. 
R. Kelley, Bureau of Public Roads, and G. C. Dignan, Bureau of Animal Industry, for assistance in col- 
lecting the data, and to Prof. J. I. Falconer, University of Ohio, Prof. O. G. Lloyd, Purdue University, 
and Prof. W. F. Handschin, University of Illinois, for assistance in the selection of the areas studied and 
for many courtesies to the investigators while the work was in progress. 
56390°— 21— Bull. 997 1 
