48 AGRICULTURE 



really good enough to suit us in all qualities except one. 

 Suppose it is desired to increase the number of ears on 

 one stalk. Rapid increase, in this case, would come 

 from selecting our seed ears only from plants bearing sev- 

 eral ears. Among these several-eared plants preference 

 would be given to those that have the other desirable 

 qualities in the greatest degree. 



Mixture of pollen from inferior plants. This improve- 

 ment by selection could not be made if the ear selected 

 were planted where the pollen from a field of poor, unim- 

 proved corn would reach the silks (Fig. 37). If some of 

 the stalks in the field are poor or barren, as shown by 

 having no ear-shoot, the tassels of such plants should be 

 pulled off before the pollen has begun to fall. 



The improvement by selection goes on more rapidly if 

 the offspring of each of the best plants is planted sepa- 

 rately. It is best to plant each set of seeds in a separate 

 row. Selection should be made for planting the seed- 

 patch the next year by choosing the ears from the most 

 productive plants on the best row, or the choice cotton 

 plants in the best row of cotton. Unfortunately the plants 

 of field corn, of cotton, and of most cultivated plants do 

 not show resemblance to the pollen-bearing parent the 

 first season. The crop of common field corn does not 

 suffer in yield the first season from a cross with inferior 

 pollen. The next season, however, the corn from such 

 crosses is poor, and even the best ears thus produced will 

 not bear uniform offspring. Popcorn and sweet corn 

 may show the change the first year. 



Temporary and permanent improvement It is difficult 



