CROP PRODUCTION IN THE GREAT PLAINS AREA. 9 
There is a saving in cultivation during the spring while the green- 
manure crop is growing, hut this is partially offset by the necessity of a 
second plowing to turn this crop under and is not sufficient to make 
up for the cost of seed and seeding. The yields have not been com- 
mensurate with the increase in the cost of producing them. At no 
station have the average yields following any green manure exceeded 
those from summer- tilled land. At all stations except Huntley and 
Dickinson the result has been a monetary loss, both actually and in 
comparison with other methods. These are the two stations that 
have had the highest average yields. 
It is hardly fair to charge the whole expense of green manuring to 
the one crop that immediately follows it, as is here done, as it should 
have a cumulative effect in building up the soil or remedying its defi- 
ciency in organic matter. The available evidence is that on normal 
soils in the Great Plains area, at least in the first years of the work, 
little effect is shown on any other than the first crop. This effect is 
like that of a fallow, in that water is stored during the period after the 
crop is plowed under. 
WINTER WHEAT. 
Cultural methods for winter wheat have been under trial at all sta- 
tions except those in North Dakota. No varieties at present avail- 
able have sufficient hardiness to survive the winters in that State. 
In the rest of the Great Plains winter wheat is more successful. In 
dry falls there is trouble in getting germination and a good stand with 
some methods. At some of the stations there is more or less trouble 
with winterkilling. When winter wheat fails to start in the fall or to 
survive the winter it can often be successfully replaced with spring- 
sown varieties. When it survives the winter, it is quite generally 
more productive than spring wheat. At those stations where it is 
adapted it makes a greater response to cultural methods, particularly 
to summer tillage, than does spring wheat. Table III presents the 
average yields and the average profit or loss from each cultural method 
at each of the stations at which the crop has been under trial. 
At Garden City, Dalhart, and Amarillo there have been so many 
failures and such poor yields when a crop was produced that the 
averages are very low. At these three stations the only material 
difference in the results from different methods has been a small 
increase in yields on summer-tilled land at Amarillo. This increase 
in the crop has not, been proportionally as great, however, as the 
increase in the cost of production by the use of this method. The 
only profit from winter wheat by any method at these three stations 
has been 8 cents per acre on disked corn ground at Amarillo. 
At the Judith Basin and Huntley stations the season is so short that 
it is not possible to make much difference in the time of plowing for 
winter wheat. The difference has been in depth of plowing rather 
