26 



BULLETIN 1039, U. S. DEPARTMENT OF AGRICULTURE. 



of the Crimean group have given satisfactory yields. The x\lton 

 (Ghirka Winter) and Buffum No. 17 varieties were somewhat prom- 

 ising, but were inferior to Turkey in both yield and quality. 



COMPARISON OF SPRING AND WINTER WHEATS. 



A comparison of the annual and average yields of Kharkof winter 

 wheat with Kubanka durum and Power common spring wheats is 

 shown in Table XVII. The average yields also are shown graphi- 

 cally in figure T. No winter wheat was sown in the cereal experi- 

 ments in the fall of 1918, so the yield of winter wheat shown Avas ob- 

 tained from a plat of the Turkey variety on fallow^ed land in the ex- 

 jDeriments of the Office of Dry-Land Agriculture. The Kubanka and 

 Power varieties were grown in the spring- wheat varietal experiments 

 each year. Kubanka spring wheat, C. I. No. 1440, was sown in the 

 same series with the winter wheat varieties from 1913 to 1917, in- 



/O A5" 20 



2S 



SPP/A/0 COMAfOA/' 



Fig. 7. — Diagram showing the average yields, iii bushels per acre, of the best varieties oi 

 winter wheat and of durum and common spring wheat on dry land at the Belle Fourche 

 Experiment Farm for the 12-year period from 1908 to 1919, inclusive. 



elusive. The average yield during this 5-year period was the same as 

 for Kubanka, C. I. No. 1516, in the spring- wheat varietal experiment, 

 so the yields of the latter are shown here. In 1914 the spring wheat 

 was sown on corn ground instead of fallowed land, so the yields are 

 not entirely comparable Avith those of winter wheat, which was 

 grown on fallow every year. Plats of Kharkof Avinter wheat, Ku- 

 banka spring Avheat, and Swedish winter rye are shoAvn in figure 8. 



The crops of both Avinter and spring wheat in 1911 and 1912 Avere 

 destroyed by drought. The 1918 crop of Avinter wheat Avas destroj'ed 

 by fall drought, Avinterkilling, and soil bloAving. 



Kharkof winter wheat has outyielded Kubanka durum, the highest 

 yielding variety of spring wheat, in 7 out of 10 years in which a 

 crop Avas obtained. The aA^erage yield of Kharkof is 20.7 bushels 

 per acre, compared Avith 17.5 bushels of Kubanka and 12.9 bushels 

 of PoAver. The crops of winter wheat in 1916, 1917, and 1918 were 

 damaged by soil blowing and winterkilling, so that spring Avheat 

 Avas more successful during this period. The Kharkof variety was 

 injured by rust in 1916 more than Kubanka, AA'hich is rather resistant. 



