16 BULLETIN 297, U. S. DEPARTMENT OF AGRICULTURE. 



ence in yield between the durum and common varieties that appears 

 plausible is that the durum wheats bloomed during a hot, dry period, 

 about June 20, while most of the common varieties bloomed about a 

 week later, when weather conditions were more favorable. Low 

 yields of durum wheat were obtained at several stations in the Great 

 Plains in 1910 and 1911, and in every case it was noted that the durum 

 varieties bloomed during a hot, dry period. This matter has been 

 discussed more at length by the writer in another publication. 1 



The crop season of 1911 was so dry that spring grain sown at the 

 usual time did not germinate till August. Table II shows that the 

 total precipitation from March to July, inclusive, was only 2.01 

 inches and that, with one exception, this precipitation came in such 

 small showers that it was of no value in promoting crop growth. No 

 yields of any of the cereals were produced that year. 



The soil was so dry in the spring of 1912 that only small yields were 

 produced that year, even though the precipitation was nearly normal. 

 The rainfall during May and June was light, and this factor con- 

 tributed further toward the partial failure of the crops. In that year 

 all the replicated plats of only two varieties of spring wheat, the 

 Ghirka and Manchuria, were harvested. Only single plats of the 

 Changli and Marquis were grown; these produced the yields shown in 

 Table IX. None of the other varieties produced enough grain to har- 

 vest. All four of the varieties which matured grain in 1912 are early 

 and so in a measure escaped the effect of the drought. 



In 1913 five fiftieth-acre plats of each variety were sown, but on a 

 portion of the area the germination and growth were not at all uni- 

 form, probably due to the replowing of the land the previous summer 

 to eradicate gumbo weed. ' Two plats of each variety were sown on 

 land which received uniform treatment, so the results from these plats 

 only are included in Table IX. 



Two plats of the Galgalos wheat, C. I. No. 2398, a beardless variety 

 with short, stiff straw and a rather large, soft, white kernel, were 

 grown on land not entirely comparable with that on which the varie- 

 ties shown in Table IX were sown. Plats of the Kubanka and Power 

 were grown, however, on the same area. The Galgalos produced an 

 average yield of 17.5 bushels, the Kubanka 18.1 bushels, and the 

 Power 14.3 bushels. 



SUMMARY OF YIELDS OF SPRING WHEAT. 



Of the numerous varieties of spring wheat grown at Newell, only 10 

 have been included in the test for the entire period of six years. Of 

 these 10 varieties, 5 are durum and 5 are common wheats. Of the 

 col mi wheats, 3 belong to the Fife group, 1 to the bluestem, and 1, 



1 Salmon, Cecil, sterile llorets in wheat and other cereals. In Jour. Amcr. Soc. Agron., v. 6, no. l, 

 p. 24-30, 2 pi., mil. 



