EXPERIMENTS WITH DtTB-TJM WHEAT. 



21 



merit Station, and the data given in Table V are taken from publi- 

 cations of that station (Lyon, 1903; Lyon and Keyser, 1905). The 

 principal data are shown also graphically in figure 8. 



Table V. — Yields of seven varieties of durum vjheat and three varieties of common 

 wheat grown at the Nebraska Agricultural Experiment Station, Lincoln, Nebr., in 

 1902. 



Class, group, and variety. 



Yield per 



acre 

 (bushels). 



Class, group, and variety. 



Yield per 



acre 

 (bushels). 



Durum: 



16.5 

 14.5 

 14.0 

 12.5 

 10.5 

 7.5 



Durum — Continued. 



7.3 





Common: 



Crimean (•winter) — 



Turkey 





Yellow Gharnovka 











33.2 







29.2 





Kharkof 



22.3 









As shown in Table V, the durum wheats were tested at Lincoln in 

 but a single year, 1902. Lincoln lies in the heart of the hard winter- 

 wheat belt, and spring-sown wheat can not compete with the varie- 

 ties of the Crimean group. The average yield of the seven durum 

 varieties is only 11.8 bushels, whereas the average yield of the three 

 Crimean varieties is 26.2 bushels per acre. The yield of the best 

 durum, Gharnovka, in the Kubanka group, is 16.5 bushels, whereas 

 the yield of the best Crimean, Turkey, is 33.2 bushels per acre, or 

 exactly double the yield of the Gharnovka. On the basis of known 

 facts, there was no economic reason for continuing further a varietal 

 experiment with durum wheat at Lincoln. 



RESULTS AT AMES, IOWA. 



Ames, Iowa, as seen from Table II, is located on the Marshall silt- 

 loam soil at an altitude of 922 feet. The average annual rainfall 

 for a 40-year period is 32.6 inches. The experiments cited were con- 

 ducted cooperatively by the Iowa Agricultural Experiment Station 

 and the Office of Cereal Investigations. 



Experiments including durum wheat cover the 5-year period from 

 1906 to 1910, inclusive. The results are given in Table VI, and the 

 principal ones are shown graphically in figure 8. 



Among the durums only Kubanka was tried, and the results are 

 unfavorable when compared with those from the other varieties. 

 None of the spring wheats does well, but all three of the spring com- 

 mon varieties are better than Kubanka. As might be expected hi 

 central Iowa, whiter wheat is much more productive than any 

 spring wheat. The 5-year average yield of Turkey, of the Crimean 

 group, is nearly 10 bushels higher than that of the best spring com- 

 mon wheat. Durum wheats have no place in so humid a climate as 

 that of central Iowa. 



