EXPERIMENTS WITH DURUM WHEAT. 



43 



. The most striking fact in Table XX is the very close agreement 

 of average yields for long periods. The average yields of the five 

 durum varieties in the 11-year period range only from 20.1 bushels 

 to 21.5 bushels per acre. The yield of Haynes is 15 bushels and of 

 Bysting 14.9 bushels in the same period. In the 6-year period, 

 1908-1913, inclusive, Preston, Rysting, and Haynes vary only 0.2 

 bushel in average yield. 



In the Edgeley district a durum wheat is decidedly the best wheat 

 to grow. This conclusion is borne out also by the fact that the 

 greatest density of durum production is in that section of the State. 

 Among the five varieties tested, Arnautka has proved slightly the 

 best adapted, outyielding Kubanka by 1.4 bushels in all 11 years. 

 This result is in accord with those obtained at Brookings, S. Dak., 

 and Crookston, Minn., discussed in the subhumid prairie section. 



RESULTS AT LAXGDON, N. DAK. 



The Langdon substation of the North Dakota Agricultural Experi- 

 ment Station is located on a black clay-loam soil at an altitude of 

 1,615 feet. The average annual rainfall in a 4-year period has been 

 17.9 inches. The substation is operated independently by the North 

 Dakota Agricultural Experiment Station, and the results obtained 

 have been published in annual reports, from which source they are 

 presented here (Stewart, 1910-1914). 



Data are available for only the five years, 1909 to 1913, inclusive. 

 These are found in Table XXI, and the principal ones in figure 12. 

 The results are all definitely and significantly in favor of the durum 

 wheats. 



Table XXI. — Annual and average yields of six varieties of durum wheat and three varieties 

 of common wheat grown at the Langdon (N. Dak.) substation during periods of varying 

 length in the five years from 1909 to 1913, inclusive. 





C.I. 



No. 



Yield per acre (bushels). 



Class, group, and variety. 



1909 



1910 



1911 



1912 



1913 



Average. 





4 years, 

 1909 to 

 1912. 



4 years, 

 1910 to 

 1913. 



■5 vears, 



1909 to 



1913. 



Durum: 



Kubanka— 



1494 

 1443 

 1350 

 1349 

 1444 

 1445 



30.8 

 25.2 

 29.8 

 25.0 



24.2 

 16.8 



15.3 

 13.6 

 12.0 

 11.2 

 9.6 

 9.7 



7.5 

 10.7 



8.0 



29.4 

 29.6 

 25.5 

 27.0 



24.2 

 27.6 



19.2 

 17.1 

 17.5 



34.7 

 35.7 

 32.7 

 31.3 

 30.7 

 24.1 



32.3 

 27.2 

 27.5 



21.6 

 24.3 

 21.7 

 23.1 



18.7 

 21.5 

 22.8 



27.6 

 26.0 

 25.0 

 23.6 

 22.2 

 19.6 



18.9 

 18.1 



25.2 

 25.6 

 23.0 

 23.2 



26.4 





25.7 





24.3 

 23.5 













Common: 



Preston— "Velvet Chaff, " No. 13. . 



19.4 

 19.1 

 19.0 





Fife— Glyndon (Minn. No. 163) 



Bluestem— Haynes (Minn. No. 169) . . 



2873 

 2874 



20.5 



19.4 



19.4 

 19.0 



