MACHINERY COST OF FARM OPERATIONS. 



11 



at all. The total cost of repairs during the life of the spike-tooth 

 harrow in this section amounts to only 20 per cent of the first cost 

 of the implement. 



THE DISK HARROW. 



The disk harrows used in western New York (Table VI) show an 

 average of 13 years, 457 acres, and 54 days of actual work. The 

 9-foot disk harrow, working 99 acres annually, as compared with a 

 5^-foot disk harrow, covering 16.7 acres annually, or one-sixth as 

 much, lasts only two years less, covers five times as much land before 

 wearing out, and works four times as many days. The cost of the 

 larger implement exceeds that of the smaller by only 25 to 30 per 

 cent. The farmer who has the greatest use for a disk harrow obtains 

 the greatest return per day and per acre on his investment. 



The depreciation charge against the disk harrow averages $0,059 

 per acre and the interest charge $0,025 per acre. The disk harrow 

 is a much more expensive implement per acre than is the spike-tooth 

 harrow or the spring-tooth harrow. Farmers who can use the larger 

 disk harrows drawn by larger teams working over large acreages 

 annually are seen to have a very great advantage economically in the 

 matter of overhead charges. 



Table VI. — Disk harrows — relation of work done annually to service and cost per acre 

 and per- day used on 73S farms. 



Range of area covered annually acres 



Number of records included 



Average area covered annually acres 



Years of service rendered 



Acres covered during life .' 



Days actually used during life 



Average width of harrow feet 



Cost when new 



Total cost of repairs during life 



Total interest during life, at 6 per cent 



Total of depreciation, interest, and repairs during life 



Cost of disk harrow: 



Per day used 



Per acre disked 



1 to 25. 



26 to 50. 



51 and 

 over. 



Average. 



374 

 16.7 

 13.8 

 230.5 

 30 

 5.5 



$25. 00 

 5.80 

 11.18 



$1.40 

 .182 



271 



38.8 



12.4 



481.1 



55 



6.8 



93 



99.0 



11.7 



1, 158. 3 



121 



9.0 



$28. 00 

 5.83 

 11.28 



$32. 00 

 10.30 

 12.17 



3.82 

 .094 



3.45 



.047 



35.2 



13.0 



457.6 



54 



6.4 



527. 00 

 6.50 

 11.31 



44.81 



3.83 

 .098 



Disk harrows are operated in this section at an average cost of 

 $0,014 per acre for repairs. From Table VI it appears the total 

 amount of repairs during the life of the average 6-foot disk harrow 

 is $6.50, or about 24 per cent of the first cost of the machine. 



THE LAND ROLLER. 



The land roller is an implement which is subjected to a minimum 

 of wear in use. From Table VII it is seen that a roller that covers 

 2,100 acres lasts nearly as long as one that covers less than 500 acres. 



