8 BULLETIN 218, U. S. DEPARTMENT OF AGEICULTUEE. 
overshadowed by the effects of the cropping and cultivation of a 
single year. This is due to the fact that the controllable factors are 
water supply, physical condition of the seed bed, and a certain 
recognized, if not understood, effect of the crop immediately preceding. 
Uniformity in these factors is largely restored by the cultivation or 
cropping of a single season. After a careful study of the data, it 
seems advisable at the present time to prepare a series of bulletins 
discussing in each the results relating to but one crop as determined 
by the treatment of the land in only the one year immediately pre- 
ceding the growth of the crop. 
COMPARISON OF CULTURAL METHODS. 
The methods under study vary a great deal in the labor involved 
and in the consequent cost of production by each method. Table 
IV has therefore been compiled hi order to show the average cost by 
each of the methods under study. These data have been prepared 
from the records of eight representative stations. An average of 
the records for 5} years at each station has been used in preparing it. 
This is equivalent to a record of 44 years at one station. An accu- 
rate record has been kept of all the farm operations performed in 
the various methods under trial. These have been averaged for the 
eight stations. The amount of work required for some methods of 
treatment varies with the season and with the soil, and the expense 
of some operations varies with the soil. The amount of labor per- 
formed under each of the methods was neither more nor less than 
that which the man in charge believed to be necessary to bring about 
the results sought. 
In computing the cost of the various operations a fixed wage of $2 
a day for a man and $1 a day for a horse was adopted. This may 
be above or below the actual labor cost in any particular locality, 
but it is believed to be a fair average and one that will afford a profit- 
able market to the farmer for his labor. The time required of men 
and teams to cover a given acreage in each of the several farm opera- 
tions obviously varies with soils and other conditions. The average 
shown in Table II has been determined from the actual experience 
of a large number of men connected with these investigations, ex- 
perience that has extended over a wide range of conditions and 
many years of time. 
The factors included in the cost of production are calculated on an 
acre basis for each of the separate operations performed, beginning 
with the preparation of the land and ending with the harvesting and 
shocking of the grain. To these items are added the cost of seed 
at 60 cents per acre, interest and taxes on the land investment 
calculated at 8 per cent on a valuation of $20 per acre, and the 
deterioration and repairs of the binder at 15 cents per acre. No 
