12 DRY-LAXD GRAIXS FOE NORTH AND SOUTH DAKOTA. 



1908 (Table III), a dry 3"ear, but in 1909, a season of abundant 

 precipitation, it was slightly exceeded in yield by other yarieties. 

 At Highmore in 1904, the driest year during which tests haye been 

 conducted, three strains of the Kubanka, G. I. Nos. 1440, 1516, and 

 1541, ranked in yield first, second, and third, respectiyely (Table 

 IV). Likewise at Dickinson in 1909, with a rainfall considerably 

 aboye the normal, the Kubanka was outyielded by other yarieties, 

 but in 1907, the driest year, it yielded the highest. While such 

 comparisons do not liold true for each year at each experiment farm, 

 it appears tliat the Kubanka is better adapted than other yarieties 

 of durum wheat to dry climates and dry seasons. It is yery prob- 

 able that for a period of years during which the precipitation 

 approaches more nearly tlie normal than has been the case during 

 the past few seasons, or when the precipitation is below normal, 

 the superiority of the Kubanka yariety will be more clearly shown. 



COMPARISON' OF DURUM AND COMMOX SPRING WHEAT. 



An important result of the yariety tests is definite information 

 concerning the comparatiye yields of durum and common spring 

 wheat. It has been pointed out that the superiority in ayerage 

 yield of the best durum oyer the best common spring wheat has 

 amounted to from 18 to 48 per cent of the yield of the common 

 wheat, the smallest difference being at Dickinson. As preyiously 

 noted, the ayerage precipitation at each experiment farm for the 

 period during which these comparisons are made is from 1 to 5 

 inches aboye normal. This has undoubtedly resulted in a diiTer- 

 ence less than would otherwise be the case, since it is only in dry 

 years that the full yalue of the durum wheat becomes apparent. For 

 example, at Highmore in 1906, with a seasonal precipitation of about 

 1 inch aboye normal, the difference in yield between the Pedigreed 

 Bluestem yariety and the Kubanka was 12.2 bushels. The increase 

 from growing the Kubanka in this case amounted to about 75 per 

 cent. In 1904, with a precipitation of about 4 inches below normal, 

 the difference in yield in fayor of the Kubanka amounted to nearly 

 100 per cent of the yield of the Pedigreed Bluestem. 



At Dickinson the driest year since the yariety tests were begun 

 was 1907. The difference in yield that season })etween the Kubanka 

 and the Ghirka Spring yarieties was 9 bushels per acre, and between 

 the Kubanka and the Bluestem 12.9 bushels, or a gain for the 

 Kubanka in the latter case of nearly 69 per cent. As the seasonal 

 precipitation in 1907 was just about normal, it seems yery probable 



[Cir. 59] 



