30 BULLETIN 218, U. S. DEPARTMENT OF AGRICULTURE. 
When the value of the average crop is studied in connection with 
the cost of its production, as in the last part of Table XIV, less differ- 
ence is perhaps found in the resulting profits or losses than in the 
yields themselves. To this statement should be excepted green 
manuring, which has not been productive of increases in yields at 
all commensurate with their cost. The use of this method has been 
responsible for an average loss of $8.39 per acre. 
Profits and losses by all other methods come within a range of 
about $2 per acre. These differences are not sufficient to warrant 
strong recommendation of any particular method as essentially better 
than others. The indications of the evidence at hand are that the 
growth of oats will about pay for the use of land and for labor and 
other expenses incurred in their growth. 
HAYS FIELD STATION. 
The soil on which the experimental work has been conducted at 
the station at Hays, Kans., is a heavy silt loam. It carries a large 
supply of water available to a crop. Penetration to the lower depth, 
however, is slow. The very compact zone in the third foot offers 
marked resistance both to the downward passage of water and to 
the development of roots. While the evidence is not as complete 
as might be desired, it appears that the proportion of water that can 
be stored in this soil is somewhat above the average. 
The work at Hays was started in 1906. The crop that year was 
raised on land uniform for all plats. The crop of 1907 was largely 
destroyed by the green bug (spring-grain aphis) ; hence, it is not 
included in the table. The crop of 1909 was entirely destroyed by 
hail and is not included in computing average yields. Its inclusion 
would only serve to reduce the averages, and reduce the differences 
obtained from cultural conditions in other years. The crop of 1911 
is included in computing the averages as its failure was due to drought. 
Oats after wheat on both fall-plowed and spring-plowed land have 
been better than where oats followed oats. 
Fall plowing of both wheat and oat stubble has been better for the 
production of oats than spring plowing of similar stubble. 
The yields given for oats following sod land, both brcme-grass and 
alfalfa, are comparatively high. They are, however, misleading and 
should not be given weight as a measure of the producing value of sod 
at this station, as there never has been in this work a heavy or well- 
established sod to break up. 
The plat subsoiled and the one listed have both been continuously 
cropped to oats. They should be compared directly with the oats 
following oats on fall-plowed land. While there is little difference 
between the results of either subsoiling or listing, both have produced 
higher yields than plowing in either the fall or spring. 
