26 BULLETIN 618, U. S. DEPARTMENT OF AGRICULTURE. 



On the average, the durum varieties are the better at Crookston. 

 Winter wheat can not be grown successfully in this locality, and only 

 the Marquis approaches closely the best durums in yield. Among the 

 three durum varieties under test, the Kubanka and a pure-line selec- 

 tion (Minn. No. 951) closely resembling Arnautka are better adapted 

 than the Velvet Don. The Arnautka selection, which has been 

 named Mindum by the Minnesota Agricultural Experiment Station, 

 outyi elded Kubanka in the 5-year test by 1.3 bushels per acre. Here, 

 as at Brookings, S. Dak., Arnautka has proved to be slightly better 

 adapted than Kubanka. The close agreement in yield between the 

 Glyndon, Haynes, and Preston varieties is remarkable, showing that 

 here all three groups of hard spring common wheat are at home. 

 Farther east only the Bluestem group does well, but farther west it 

 is decidedly inferior to the other two. 



RESULTS AT FARGO, N. DAK. 



Fargo is located on a heavy black clay loam at an altitude of 935 

 feet above sea level. Its normal aimual rainfall is 24.9 inches. These 

 data, in comparison with those from all the other stations, will b3 

 found in Table II (p. 15). The experiments here were conducted 

 cooperatively by the North Dakota Agricultural Experiment Station 

 and the Office of Cereal Investigations. The results obtained are pre- 

 sented in Table XI. The principal data are shown graphically also 

 in figure S. 



The experiments cover seven years, 1901 to 1904, inclusive, and 

 1906 to 1908, inclusive. Eleven varieties of durum wheat are 

 included, of which 10 belong to the Kubanka group. It is striking 

 that among the 7-year average yields of these 10 there is a range 

 of only 2.9 bushels. This difference is scarcely significant when the 

 lowest and highest yields are, respectively, 33 and 35.9 bushels per 

 acre. The difference in yield between the now commonly grown 

 varieties, Arnautka and Kubanka, is not significant, although the 

 slight difference is in favor of Kubanka. Here again the durums all 

 outyield the best representatives of the standard spring common 

 wheats by quantities that usually are significant. Winter wheat can 

 not be grown successfully in this locality. 



The Bluestem slightly excels Fife, and that in turn outyields 

 Preston. In 1904, the year of a severe rust epidemic, the durums 

 yielded better than common wheats. In 1906, however, the Blue- 

 stem outyielded all durums except Arnautka. A summary of the 

 results shows that durum wheat yielded better than common wheat 

 in the Red River Valley in the 7-year period, a conclusion fully in 

 accord with farm yields in that district. Since 1908 the experi- 

 ments have been conducted independently by the North Dakota 

 Agricultural Experiment Station, but the results are not yet avail- 

 able. 



