WINTER-WHEAT PRODUCTION AT FORT HAYS STATION, 



19 



the other fallow plats are plowed or replowed. Its treatment for 

 the remainder of the season is the same as that of the others. The 

 same method is followed in the pair R-S except that some time after 

 listing in the fall a subsoiler is run in the lister furrows. Un- 

 fortunately it was necessary to locate this pair of plats in a block 

 in another part of the field. The yielding power of the land is 

 about the same, but results can not be compared too closely. The 

 yields of these plats are also given in Table 7. For the 6-year period 

 from 1915 to 1920, inclusive, the yield of P-Q has averaged 19.8 

 bushels and of R-S 22.2 bushels. In the same years H-I has aver- 

 aged 20.1 bushels, J-K 21.0 bushels, L-M 21.3 bushels, and N-0 

 22.9 bushels. 



The results of the whole experiment in methods of fallow show 

 clearly that the essential period of the fallow is the summer months 

 immediately preceding seeding. This conclusion was indicated in 

 the continuous-cropping series by the close approach of the yields 

 on early plowing to those on fallow. They also show, in connection 

 with other experiments, that the essential part of the fallow is the 

 maintenance of a bare surface (prevention of the growth of vege- 

 tation) during the active growing season and that the cultural methods 

 by which this is accomplished are of minor importance from the stand- 

 point of resultant yield. 



Table 7. — Yields of wheat from different methods of fallow at the Fort Hays branch 

 station for the 7-year period from 1914 to 1920, inclusive. 





Yields per acre by the several methods (bushels). 



Year. 



Plats 

 HI. 

 Early- 

 fall 

 plowed. 



Plats 



J-K. 



Late- 



faU 



plowed. 



Plats 



April 

 plowed. 



Plats 



N-O. 



June 



plowed. 



Plats 



P-Q. 



Fall 



listed. 



Plats 



Fall listed 

 and sub- 

 soiled. 



Rotation 



570. 

 Fallow 

 3 years. 



1914 



26.8 

 17.3 

 33.6 



6.8 

 15.3 



9.0 

 38.8 



25.6 

 20.4 

 37.3 



6.3 

 14.1 



9.8 

 37.8 



25.4 

 16.8 

 38.2 

 7.5 

 14.5 

 10.2 

 40.3 



27.3 

 16.3 

 41.2 

 1.0 

 18.3 

 22.4 

 38.4 









1915 



19.3 

 37.2 

 8.1 

 11.8 

 13.7 

 28.9 



17.8 

 38.0 

 11.8 

 17.2 

 13.3 

 35.0 



18.8 



1916 



33.1 



1917 



10.4 



1918 



28.8 



1919 



9.0 



1920 



33.8 







Average, 1914 to 1920 . 



21.1 



20.1 



21.6 

 21.0 



21.8 

 21.3 



23.6 

 22.9 



... .1 





Average, 1915 to 1920 



19.8 



22.2 



22.3 



An experiment started in 1913 to provide material for the study 

 of certain water relations of the soil is interesting in its evidence on 

 the effect of the length of fallow. On the four plats known as 

 rotation No. 570 the land is fallowed for three years and then cropped 

 to winter wheat. These plats adjoin the pair R-S in the field. The 

 yields from 1915 to 1920 are given in Table 7. The average yield 

 for this period is 22.3 bushels per acre, which is less than the highest 

 yielding plats with a single year of fallow. The only year when it 



