40 BULLETIN 218, U. S. DEPARTMENT OF AGRICULTURE. 
With the exception of a sharp decrease from subsoiling at -Akron 
and a similar increase from listing at Garden City, the yields from 
each of these practices have not departed far from the yields of 
ordinary plowing. Some of the details of departure or lack of it 
have been discussed in dealing with separate stations where closer 
comparisons could be drawn with exactly similar stubble. 
Green manuring averaged as a group was productive of higher 
yields than either fall or spring plowing or disking corn ground at 
9 of the 13 stations for which results with this method are reported. 
At Dickinson this method was exceeded by disking corn ground. At 
Hettinger, Akron, and Dalhart green manuring gave poorer yields 
than any of the three other methods mentioned. At Amarillo this 
method gave yields exceeding those by fall plowing. 
Of all the methods under trial, as grouped in Table XIX, summer 
tillage produced the highest yields at every station except Hettinger, 
where is was exceeded only by yields on disked corn ground. Aver- 
aged for all the stations, its increase of yield over fall plowing lacked 
one-tenth of a bushel of being 10 bushels per acre. The greatest 
departure from this general average was at ScottsblufT, where the 
increase was 20 bushels per acre. 
Sod breaking as a preparation for oats has very generally stood 
at or near the bottom of the list, as is discussed in some detail under 
each station where it has been on trial. 
As values and cost of production are here figured, it is seen in Table 
XIX that oats have been produced at a profit by at least one method 
at all stations except Garden City and Dalhart. At two stations, 
Judith Basin and Huntle}^, a profit has been realized by all methods. 
Generally speaking, good yields have combined with low cost of 
production to make disked land which has been chiefly corn ground 
show the greatest profit at all stations where a profit has been realized 
from any method. 
At all stations where it has been tried, listing either has been more 
profitable or has resulted in less loss than fall plowing. 
Subsoiling has yielded a profit at two stations and a loss at six. 
It can not be said, however, that it was a profitable practice at any 
station, as its profits were less and its losses greater than those of fall 
plowing. It should be compared with fall plowing, as it is a modifi- 
cation of that method. 
At all the ten stations north of Hays, except Belle Fourche and 
North Platte (where the losses were 44 cents and 29 cents, respec- 
tively), spring plowing was productive of profitable crops. At Hays 
the average loss from it was only 56 cents per acre. At Amarillo the 
loss increased to $1.31. At Garden City and Dalhart spring plowing, 
in common with all other methods, shows a loss. 
