XOKMAL DAY S WORK FOR VARIOUS FARM OPERATIONS. 
43 
(S) Since certain sizes and units of equipment are used by the 
majority of farmers, it would be impossible by any method to secure 
sufficient original data for the less common sizes and crews to yield 
averages of value. In the tables, therefore, factors have been de- 
duced for some of the less common units of equipment. These 
deduced factors are based on an analysis of general tabulations for 
each operation. For practical reference purposes the tables are thus 
made complete. 
(9) In arriving at work standards by the method here used it is 
believed that certain biased influences operate to produce averages 
somewhat above normal. In many of the tables, therefore, compen- 
sation has been made for the bias by reducing the adjusted factors 
from 5 to 20 per cent below the original averages. 
(10) The daily duty for nearly all of the major operations in 
American agriculture can be ascertained from the tables in this bul- 
letin. These work factors represent the average of conditions in the 
United States and can not be too strictly applied to every climate, 
topography, «or soil. 
(11) For convenient reference, averages of the data relating to 
field implements referred to in the text have been summarized in 
Table XLVII. 
Table XLVII. — Summary of work factors for operations with field implements. 
Operation or implement. 
Power 
unit 
(number 
of 
horses). 
Daily 
duty 
per 
foot of 
width. 
Range of reported widths. 
Most 
usual 
width 
per 
horse. 
2 
3 
2 
3 
4 
4 
5 
6 
fl5 to 60 
•j horse- 
[ power. 
} 2 
| 3 
Acres. 
1.62 
2.00 
1.61 
2.13 
2.23 
2.08 
2.21 
2.20 
| 2.00 
/ 1.40 
\ 1.60 
/ 1.50 
\ 1.80 
/ 1.70 
\ 2.00 
/ 1.20 
\ 1.40 
/ 1.30 
\ 1.60 
/ 1.50 
\ 1.70 
/ 1.10 
\ 1.20 
/ 1.20 
\ 1.50 
/ 1.60 
\ 1.90 
1.60 
1.65 
1.75 
8 to 14 inches 
Feet. 
0.50 
10 to 16 inches 
10 to 16 inches.. 
.44 
.58 
12 to 16 inches 
.44 
14 to 18 inches 
.33 
18 to 28 inches... 
.58 
24 to 28 inches 
.47 
24 to 32 inches 
.39 
4 to 30 feet 
.33 
Spike-tooth, harrow: 
J6 to 12 feet 
4.00 
}s to 16 feet 
| 4 
> 9 
}l0 to 26 feet. .. 
On fresh plowing 
On well-packed land 
4.25 
\i to 8 feet 
Spring-tooth harrow: 
3.00 
On well-packed land j 
On fresh plowing .\ o 
\o to 10 feet 
2.33 
On well-packed land 
I 4 
I 2 
} 3 
| 4 
/ 
On fresh plowing 
J6 to 12 feet 
2.07 
3.00 
J4 to 8 feet 
Disk harrow: 
On fresh plowing 
On well-packed land 
\& to 10 feet 
2.25 
On well-packed land 
J6to 10 feet 
On fresh plowing 
2.00 
On well-packed land 
2 
3 
4 
5 to 12 feet 
4.00 
5 to 12 feet. . 
2.00 
8 to 16 feet 
2.50 
