232 ILLINOIS DAIRYMEN'S ASSOCIATION. 



is as nearly as possible of the same breeding as that planted in the breed- 

 ing plot itself. The stock seed for this field should always be selected 

 from the previous year's breeding plot and it may well include as many 

 of the 160 rejected ears as are known to be above the average of the 

 200. Or, if the breeding plot can be well isolated from all other corn 

 fields and still occupy good soil, this also makes a very suitable location 

 for it. 



The very best ears of seed corn are planted in the center rows of the 

 breeding plot, the remainder of the ears being planted in approximately 

 uniform gradation to either side, so that the least desirable ears among 

 the 40 are planted in the outside rows; and in the final selection of the 

 best field rows from which the next year's seed ears are to be taken, some 

 preference is given to the rows near the center of the plot. 



While we are not yet ready to make absolute statements regarding 

 the matter, never the less, from the data which we have secured, and are 

 securing upon the subject, we now recommend that every alternate row 

 of corn in fhe breeding plot be completely detasseled before the pollen 

 matures and that all of the seed corn to be taken from the plot be selected 

 from these 20 detasseled rows. This method absolutely prohibits self- 

 pollenation or close-pollenation of the future seed. By self-pollenation is 

 meant the transfer of pollen from the mail flower of a given plant to the 

 female flower of the same plant; and by close-pollenation Is meant the 

 transfer of pollen from the male flower of one plant to the female flower 

 of another plant in the same row, both of which grew from kernels from 

 the same seed ear. 



The transfer of pollen from one plant to another plant which which 

 grew from kernels from a different seed ear, we term cross-pollenation. 

 We have been for several years accumulating data which show that arti- 

 ficial self-pollenation is very injurious to the vitality and vigor of the 

 seed produced, and we have also secured data pointing toward an injurious 

 effect of close-pollenation even by natural methods, so that we feel justi- 

 fied in recommending, at least tentatively, the use of cross-pollenation in 

 seed corn breeding. 



It is also recommended that in the 20 rows of corn which are not 

 detasseled no plants which appear imperfect, dwarfted, immature, barren, 



