TESTS IN MARYLAND. 9 



reliable methods and tlie losses that may result from following 

 erroneous methods along these lines are tremendous because of the 

 great extent to which corn is grown. 



As acclimatization, crossbreeding, and selection have proved effi- 

 cient in increasing the productiveness of corn, the question of practi- 

 cal importance is a determination of the best combination of these 

 influencing factors. All these factors necessaril}' have a strong bear- 

 ing upon the results presented in this j)aper. These results are pre- 

 sented here, however, with especial reference to the comparative 

 I)roductiveness of first-generation crosses and their parent varieties. 

 In a future bulletin the results in these tests attributable to the 

 efi'ects of acclimatization and adaptation will be combined with 

 results of other work and treated with especial reference to these 

 factors and their mfluence upon yield. 



TESTS IN MARYLAND. 



WORK OF 1909. 



CHOICE OF VARIETIES. 



In order to make the tests of as much practical value as possible, 

 varieties grown by successful corn growers in Maryland and adjoining 

 States were chosen. Composite samples shelled from a hundred or 

 more ears were used in order to equalize results of mdividual ear 

 variations. 



Detailed information regarding the history and description of 

 these varieties is given in Table I, together with the germinating 

 power of each lot of seed, both in the spring of 1909 and of 1910. 

 12305°— Bui. 218—12 2 



