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



The best average yield of any spring common wheat is slightly 

 lower than the lowest average yield of any durum wheat in the same 

 period of years. Among the common varieties, Glyndon has the best 

 5-year average, 19.4 bushels per acre, while for the same period the 

 average yield of Arnautka is 26.4 bushels per acre. All three of the 

 standard spring common varieties are in close agreement in average 

 yield during the 4-year and 5-year periods. 



At Langdon there is more difference between the yields of the 

 different durum wheats than is usually the case. All four of the 

 varieties in the Kubanka group distinctly outyield Velvet Don. 

 Within the Kubanka group, Arnautka (C. I. No. 1494) leads, out- 

 yielding Kubanka (C. I. No. 1349) by nearly 3 bushels per acre. 

 These results substantiate further the results obtained at other 

 stations in the Red River and Big Sioux valleys and territory adjacent 

 thereto, showing the Arnautka variety to be best adapted to that 

 section. 



RESULTS AT DICKINSON, N. DAK. 



The Dickinson substation of the North Dakota Agricultural Experi- 

 ment Station is located on the border of the Heart River valley on a 

 soil varying from sandy loam to clay loam. The elevation is 2,453 

 feet, and the average annual precipitation has been 15.7 inches in a 

 24-year period. The experiments were conducted cooperatively by 

 the North Dakota Agricultural Experiment Station and the Office of 

 Cereal Investigations. 



The results will be found in Table XXII, and the principal data in 

 graphic form in figure 12. Experiments have been in progress for 11 

 years, but the wheat crop of 1912 was destroyed by hail. Here, as 

 elsewhere in the State, the durum varieties have outyielded .all 

 varieties of spring common wheat by quantities that are significant. 

 Kubanka and Arnautka are the only durums grown throughout the 

 10-year period. Here Kubanka has proved a slightly better yielder 

 than Arnautka. In a 5-year period the two excel all other durums. 

 During a 7-year period they in turn have been outyielded by a pure- 

 line selection of Kubanka (C. I. No. 1440). This selection, first known 

 as Kubanka No. 8, is now known as Cereal Investigations No. 4063. 

 In this period it had an average yield of 3.3 bushels greater than the 

 parent Kubanka. In the last 4 years of the test all the varieties were 

 exceeded in yield by the new and more rust-resistant variety, dis- 

 tributed as "Dl" but now named Monad. 1 



Among the spring common wheats, Fife leads in yield, with Preston 

 next and Bluestem last. Only Rysting and Haynes have been grown 

 throughout the period. In the last four years Marquis has produced 



1 This name is derived from mona, the Greek word for one, plus d, which stands for durum. This variety 

 was obtained in Russia by Prof. H. L. Bolley, of the North Dakota Agricultural Experiment Station, 

 and was further selected by him at Fargo. 



