6 BULLETIN 1198, U. S. DEPARTMENT OF AGRICULTURE. 
man-labor requirement of less than four hours per acre the wheat was 
drilled in on disk-harrowed stubble land (see fig. 3), while on the 
other farm the crop was seeded on listed land without additional 
preparation. Yields were very low on both farms, with the result 
that the time required for threshing and marketing was relatively 
low. The acreage in wheat on the farms with man-labor require- 
ments of 20 hours and over per acre averaged less than 50 acres per 
farm; the land was given a thorough preparation and the yield of 
wheat was high, requiring a relatively long time to thresh and market. 
In Missouri and in Gage County, Nebr., the majority of the farms 
are represented in the groups having man-hour requirements of from 
10 to 18 hours per acre, while in all other counties the majority of the 
farms fall within the 4 to 12 hour group. For all farms 60 per cent 
had man-hour requirements of from 4 to 12 hours per acre, while 32 
_per cent had man-hour requirements ranging from 12 to 18 hours per 
acre. 
Fic. 3—Disking stubble land prior to drilling wheat without further preparation. This is a com- 
mon method of preparing the seed bed for wheat in Cheyenne County, Nebr. 
The average man-hour requirement for all districts was 8.8 per 
acre, with a corresponding horsepower requirement of 23.6 hours per 
acre. Variation by groups of these requirements was from 3 to 22.6 
ee nour per acre and from 8.1 to 50.2 horse hours per acre. (See 
able 4. . : 
EFFECT OF USE OF TRACTOR ON TOTAL MAN AND HORSE HOUR REQUIREMENTS. 
A comparison of the man and horse hours required to grow an 
acre of wheat on farms where no tractors were owned. with the man, 
horse, and tractor requirements per acre on farms where tractors 
were owned, is shown for three counties in Table 5. Although in 
each county the crop area per farm was larger on the tractor-owned 
farms than on those operated by horses, the tillable acreage per farm 
in each group is large enough to make the data comparable. The 
part of the total acreage covered by different operations varied con- 
siderably and these variations had a direct effect on the relative 
amount of work required. per acre. 
