QUANTITY 123 



say in 1910 — several are seriously depressed when the 

 winter has been severe. This having been observed, 

 it was determined that crosses should be made between 

 some of the " winter soft " varieties which yielded well 

 ordinarily and others which were " winter hard " in the 

 hope that the desirable qualities in both parents might be 

 combined in some of their progeny. 



Crosses were made before 1900, but, since the appoint- 

 ment at that time of Dr. Nilsson-Ehle to take charge 

 of the experiments in wheat and oats, crossing and the 

 selection of new varieties from the descendants has 

 been adopted as the chief means of improvement. The 

 details of what has been accomplished, so far as we 

 are now concerned, are to be found in his paper " Berat- 

 telse ofver foratlingsarbetena med hosthvete vid Svalof, 

 1910-1912." 



Two varieties mentioned in the foregoing table, Extra 

 Squarehead and Grenadier II, were crossed in the hope 

 of combining the power of the former to resist rust and 

 winter with the higher yield and power of the latter 

 to resist lodging ; and, when the progeny had been 

 produced, the pure-breeding individuals identified, a 

 stock of their descendants accumulated, and the best 

 yielder determined by the necessary measuring and 

 weighing, there resulted the new variety Extra Square- 

 head II, which was sent out to the farmers in the year 

 1909. The following table gives the average yield of 

 this variety as compared with those of its parents and 

 the standard native variety, Sammets wheat, over the 

 years 1907 to 1912, excepting that the average for 

 Extra Squarehead covers the years 1907 to 1910 

 only: 



