TESTS IN TEXAS. 37 



Sherman and more moisture was available for the growing crop; 

 higher yields were made, but Chisholm seems to be less suited to the 

 conditions than most of the other varieties. The female parents 

 made an increase of 223 per cent in average production per stalk over 

 their average production per stalk at Sherman; the same increase for 

 Chisholm is 186 per cent. The results at Corsicana were similar and 

 as pronounced, although actual yields were lower than at Waco. 



As has been stated, Chisholm at Sherman, to which conditions it 

 has been thoroughly adapted, outyielded the cross in 9 out of 15 

 comparisons. At Waco, planted in the deep, sandy soil of the Brazos 

 Valley, conditions to which the variety is apparently not adapted, it 

 is outyielded by the cross in 10 out of 12 comparisons. At Corsicana, 

 under conditions to which it was apparently also not adapted, it is 

 outyielded by the cross in 10 out of 14 comparisons. 



In the Waco and Corsicana tests the crosses in the majority of 

 comparisons outyielded the parent varieties. None of the varieties 

 used in the tests had been bred for any length of time for the environ- 

 mental conditions encountered at either place. At Sherman the 

 Chisholm variety, wdiich has been grown for many years in that 

 locality, outyielded the crosses in most of the comparisons. This 

 would indicate that in general a variety well adapted to its environ- 

 ment is not improved nor its productiveness increased by crossing 

 with other varieties possibly less adapted to the environment. Wliat 

 results would be obtained by crossing varieties that have been bred 

 in the same locality and under the same conditions for a long period 

 will have to be determined by further experimental work. Although 

 m this connection attention should be called to the fact that crosses 

 with such varieties as McCullough, Ferguson Yellow, and Singleton 

 (all established northern Texas varieties that have been bred 

 under very smiilar conditions to Chisholm) are less productive than 

 Chisholm. 



THE PRODUCTIVITY OF THE PARENT VARIETIES AND ITS INFLUENCE UPON THE 



PRODUCTIVITY OF THE CROSSES. 



In Table XII an attempt has been made to trace as far as the fifth 

 or sixth rank in yield the factors showing to what extent the highest 

 yielding crosses are progeny of the highest yielding varieties ; also to 

 what extent the highest yieldmg crosses may be identical with the 

 crosses showing highest percentage of gain over better parent. 



Table XIII is a similar enumeration of the poorest yielding varie- 

 ties, poorest yielding crosses, and crosses showmg the greatest per- 

 centage of decrease as compared with the better parent. 



In the Sherman test the six highest yieldmg crosses are identical 

 with the crosses of the six highest yielding female parents, but they 



218 



