CEREALS ON THE BELLE FOURCHE EXPERIMENT FARM. 51 



DEPTH-OF-SEEDING EXPERIMENTS. 



Depth-of-seeding experiments with Kharkof winter wheats were 

 conducted on irrigated land in 1917 and 1918. Only one fiftieth-acre 

 plat was sown at each depth in 1917, but in 1918 the experiment was 

 triplicated. The yields are shown in Table XXXVII. 



Table XXXVII. — -Yields of Kharkof tvinter wheat grown in depth-of-seeding 

 experiments on irrigated land in 1917 and 1918. 





Depth of seeding. 



Yields per acre (bushels). 





1917 



1918 



Average. 



1 inch 



24.5 

 30.0 



28.5 



35.9 

 34.2 

 32.3 



30.2 



IJ inches 



32.1 



2 inches 



30.4 







In 1917 the seeding at a depth of 1| inches gave the highest yield, 

 while in 1918 the highest average yield was obtained from seeding 

 at a depth of 1 inch. The 1^-inch depth of seeding gave the highest 

 average yield for the two years and, although the results are not 

 very conclusive, this appears to be the most favorable depth. 



COMPARISON OF SPRING AND WINTER WHEATS. 



In 1916, 1917, and 1918, three plats of Kubanka durum spring 

 wheat were sown in the spring in the same series with the winter- 

 wheat varieties for comparison. During each of these years Ku- 

 banka considerably outyielded all of the winter-wheat varieties. In 

 1915 the winter wheat was sown under very favorable soil conditions 

 and the yield was unusually high. The 4-year average yield of 

 Kharkof, C. I. No. 1583, winter wheat was 32.6 bushels per acre, 

 while Kubanka spring wheat yielded an average of 27.3 "bushels. 

 Because of the conditions in 1915, however, these yields are not quite 

 comparable. 



In the irrigated rotation experiments on the Belle Fourche Ex- 

 periment Farm, conducted by the Office of Western Irrigation Agri- 

 culture, spring and winter wheat have been grown in continuous 

 culture in adjoining plats each year since 1913. Since 1915 this test 

 has been duplicated in another part of the rotation field on better 

 soil. The yields on this good soil have been nearly twice as high as 

 on the poorer soil. The average yields from the good and poor 

 plats are used for comparison from 1915 to 1919, inclusive. The 

 same variety of spring wheat was not used during all seasons. From 

 1913 to 1915, inclusive. Regenerated Defiance, C. I. No. 3703, was 

 the variety used. In 1916 Marquis, C. I. No. 3276, was sown, but 

 since 1917 Kubanka durum spring wheat was used. Because of the 



