OATS IN THE GEE AT PLAINS AREA. II 



RESULTS AT THE SEVERAL STATIONS. 



Accompanying the discussion of each station is a very brief descrip- 

 tion of the soil, with particular reference to its depth and its water- 

 holding capacity. Only such information is given as is necessary to 

 understand fully the interpretation of the results. 



JUDITH BASIN FIELD STATION. 



The field station at Moccasin, Mont., in the Judith Basin, is located 

 on a heavy clay soil of limestone origin. The soil is apparently very 

 rich in available fertility. It is underlain at a depth of approxi- 

 mately 3 feet by a limestone gravel that is closely cemented with lime 

 materials. The gravel subsoil, which extends to a depth of about 30 

 feet, is practically free from soil. While it is so closely cemented that 

 it does not unduly drain the soil, it is not of a character that allows 

 the storage of available water or the development of roots within it. 

 The presence of gravel in the surface soil does not permit the taking 

 of samples satisfactory for the study of soil moisture. Enough has 

 been done, however, to make it certain that the supply of water that 

 can be stored in this soil is limited. This shallowness of the soil and 

 consequent limitation of the quantity of water that can be stored 

 in it and recovered by the crop makes the crop dependent in large 

 part upon the rains that fall while it is growing. 



While the oat crop is not at present the most important commercial 

 crop in the Judith Basin, good yields have been obtained at this field 

 station and a profit realized by all methods under trial. In 1912 the 

 crop was destroyed by a local hail storm. Yields have therefore 

 been calculated on the basis of five years. In the experiments in 

 crop rotation and cultivation methods, 33 plats of oats have been 

 grown each year. This number was increased by the addition of 

 new work in 1913, but only work started in 1908 is here reported. 

 As here presented, the results are arranged to study only the effect 

 of cropping and cultivation in the one year preceding the growth of 

 oats. No attempt is made to study rotations as units. 



Table V shows that while there may be great seasonal variations 

 in yields the differences resulting from cultural conditions are gener- 

 ally small. With the exception of the comparatively high yield by 

 summer tillage and the low yield on both brome-grass and alfalfa 

 sods and following flax on brome-grass sod, the differences in yield 

 from different preparations are too small to have meaning. 



The low yields on brome-grass and alfalfa sod and following flax 

 on brome-grass sod are due to the fact that at this station sod crops 

 recover after breaking to such an extent as to choke out the oats. 

 The profitableness of these crops in themselves, together with the 

 poor results which follow their breaking, indicates that the sod crops 

 should remain down for long periods rather than enter into short 

 rotations. 



