36 CROSSBREEDING CORN. 



outyields the cross in but 2 and the female in 5 out of 12 comparisons. 

 At Corsicana it outyields the cross m 4 and the female parent in 5 out 

 of 14 comparisons. The results at Waco and Corsicana are prac- 

 tically a reversal of the results with Chisholm at Sherman. 



The 5 varieties that outyield Chisholm at Sherman are Surcropper, 

 Dan Patch, Selection 137, Lily of the Valley, and Ferguson Yellow 

 Dent. The first three varieties are earlier maturing than Chishohii; 

 their increase in yield over Chisholm is considerably greater than the 

 increase of Lily of the Valley and Ferguson Yellow Dent over Chis- 

 hohn. Tliis would indicate that the superiority of the first three 

 varieties has been due cliiefly to their earliness, wliich made them 

 particularly suited to the drought conditions that prevailed at 

 Sherman in 1910. From previous experience there is reason to 

 believe that durmg a normal season Chisholm would be considerably 

 more productive than an}^ of these three varieties. The fourth 

 variety (Lily of the Valley) is another strain of the same variety as 

 Chisholm, its increase over Cliisholm is not especially significant, 

 although perhaps indicating a slight superiority, as Lily of the Valley 

 outyielded Chisholm also at Corsicana. The increase of Ferguson 

 Yellow over Chisholm is slight, and can not be regarded as indicating 

 very much, if any, superiority. Taking into consideration the aver- 

 age behavior of Chisholm in all the rows m which it was planted, it 

 perhaps should be considered as superior to any of the varieties for 

 practical growing at Sherman. 



The relativel}^ greater productiveness of Chisholm in the Sherman 

 test than at Waco and at Corsicana is due probably to the fact that 

 Chisholm is a northern Texas variety, and the particular strain used 

 in these experunents has been grown for many years on fertile black 

 lands near Sherman. This doubtless has caused the variety to be 

 better adapted to its en\aronment at Sherman than it was at Waco 

 or at Corsicana. Its yields also indicate that it was better adapted 

 to the Sherman environment than were the other varieties in the 

 test. The higher yields of the three early maturing varieties does not 

 seem to have been due to better adaptation, but rather that the 

 abnormal conditions of the season were less disastrous to them than 

 to the later maturing varieties. The increase of Ferguson Yellow 

 Dent, itself a northern Texas variety, is so slight that no generalization 

 is warranted that it is better adapted to the Sherman environment 

 than is Chisholm. 



Of the varieties used as female parents none has been bred for any 

 length of time for the conditions encountered at any of the three 

 places. At Sherman the conditions were very adverse and the yields 

 very poor. At Waco, in the Brazos Valley, conditions were more 

 favorable. The soil retained the moisture better than the soil at 



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