6 BULLETIN 268, U. S. DEPARTMENT OF AGRICULTURE. 
is considered, without reference to the previous crop. In the tables 
for corn, milo, and kafir, the tables show the effect of the previous 
crop, as well as the effect of the method. Under the headings, "Fall 
plowed," " Spring plowed/' and ''Green manured" in the tables for 
the small grains are shown the average yields obtained from ground 
so prepared following several different crops, usually wheat, oats, 
barley, or corn. The disked land has been chiefly corn land. List- 
ing and subsoiling have been done on land continuously devoted to 
the crop for which results are presented. The second part of the table 
shows the comparative profit or loss resulting from growing each 
crop by the various methods under study. The profits and losses 
are based on the average yields shown in the first part of the table. 
The method of computing the cost of production and of valuing 
the crop has been shown in detail in the publication previously cited. 1 
The cost is based on a land rental of $1.60 per acre and an average 
wage of $2 per day for a man and $1 per day for a horse. With this 
wage as a basis, the labor cost is computed on the average amount of 
work required by each method under trial. The cost of production 
as computed is not offered as. being absolute for any locality, either 
in amount or cost of labor required, but is given as a working basis 
for the comparison of the results from different methods of prepara- 
tion. 
SPRING WHEAT. 
The results with spring wheat are summarized in Table II. In 
the first part of the table are brought together for each station the 
average yields as grouped for this study under different methods of 
preparation. In the second part of the table the profit or loss in 
dollars and cents per acre for the average crop for each method is 
shown. This digest is based on the yield data presented in the 
first part of the same table. 
When fall plowing following corn, oats, and wheat is averaged 
together and compared with spring plowing following the same crops ; 
the average yields from each of the two methods at 11 of the 14 sta- 
tions show no material difference for the years averaged. At only 
three stations — Scottsbluff, Akron, and Hays — are the average dif- 
ferences greater than 1 bushel per acre. At Hays the advantage is 
with fall plowing and at the other two stations with spring plowing. 
At most stations the advantage of one method over the other depends 
chiefly upon the season. The effect of different times of plowing 
small grain stubble has been treated in detail in a separate publica- 
tion. The small difference in the cost of the two methods makes 
relative profits and losses from them follow closely the differences in 
yields. 
1 IT. S. Dept. of Agriculture Bulletin No. 214, entitled "Spring Wheat in the Great Plains area: Relation 
of cultural methods to production," 1915, p. &-11. 
