M 



BULLETIN 430, U. S. DEPARTMENT OP AGRlCULTtJRE. 



from the May 1 seeding. The results to date indicate that fairly 

 early spring sowing is to be preferred. 



COMPARISON OF WINTER AND SPRING WHEATS. 



In comparing the results from winter wheats, durum wheats, and 

 spring common wheats it is observed that (1) better yields were 

 obtained in 1913 from winter wheats, yet the difference in yield of the 

 leading varieties of winter and spring wheat was not very great. (2) 

 Better yields were obtained in 1914 from the spring wheats, the 

 winter wheats being severely winterkilled. (3) In 1915 winter-wheat 

 yields were much higher than those of spring wheat. (4) The 

 .average yields of the winter wheats in the years 1913, 1914, and 1915 

 are higher than those of any of the spring-wheat groups. (5) Durum 

 wheats stand next to winter wheat when ranked according to yield, 

 (6) Winter wheats undoubtedly will give higher yields than spring 

 wheats if winterkilling is not too severe. 



The annual and average yields of some of the leading varieties of 

 winter and spring wheats for the three years, 1913 to 191 5, are shown 

 in Table XV. 



Table XV. — Annuau and average yields of the leading varieties of winter, durum, and 

 spring common wheats grown on the Cheyenne Experiment Farm, 1913 to 1915, 

 inclusive. 



Group and variety. 



WINTER "WHEAT. 



Ghirka: 



Ghirka Winter. 

 Crimean: 



Kharkof 



Durum: 



Beloturka. 

 Common: 



Erivan 



Galgalos... 



Marquis . . . 



SPRING WHEAT. 



CI. 

 No. 



1438 

 1442 



1520 



2397 

 2398 

 3641 



Yield per acre (bushels). 



9.3 



9.4 



o7.9 



9.0 



7.8 

 4.7 



9.5 

 blO.3 



8.4 



1915 



37.6 

 37.1 



22.0 

 21.2 

 20.9 



3-year 



18.2 

 17.2 



16.2 



13.6 

 13.1 

 12.8 



a- Average of 2 tenth-acre plats. 



b Average of 3 tenth-acre plats. 



The average yields of winter and spring wheat are not strictly 

 comparable, since the winter wheats were grown on fallow in 1915, 

 while the spring wheats were grown on disked corn ground. 



It appears that it may be more profitable to grow spring wheat, 

 especially the durums, after corn if the corn crop is profitable for 

 forage. It may be possible also to grow winter wheat after corn, 

 but data are not available at present. More data must be obtained 

 before it wiU be possible to say whether winter or spring wheat is the 

 more profitable. The average yields of the leading varieties of each 

 group of wheats are shown graphically in figure 9. 



