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Table I. Plan for Planting the Breeding Plot to Avoid Inbreeding. 



The numbers given in the " Guides '' designate the field rows from which the seed ears 

 are talcen. (AH even-numbered rows are detasseled. ) 



In this plan, the breeding plot is considered by- 

 quarters. Each quarter contains twenty-four rows 

 and each row is planted with corn from a separate 

 seed ear. All even-numbered rows are detasseled 

 and seed for the next year's breeding plot is taken 

 from the six best-yielding detasseled rows in each 

 quarter, four ears being taken from each selected 

 row, making ninety-six ears in all. 



For convenience we use the term " sire seed," or 

 " sire ears," to designate the ears that are to be 



planted in odd-numbered 

 rows to produce tassel? 

 (the male flowers) and to 

 furnish pollen ; and we 

 use the term "dam seed,"" 

 or "dam ears," to desig- 

 nate the ears to be 

 planted in the even-num- 

 bered rows to produce 

 future seed ears. Of the 

 four seed ears taken 

 from each selected field 

 row, two are used for 

 sire seed and two for 

 dam seed. 



In the column headed, 

 " Guide system for even 

 years," is given a key or 

 guide by which to work 

 out the actual plan for 

 planting in all even- 

 numbered years ; and 

 under the heading, 

 " Model example for an 

 even year," is given an 

 actual plan which has 

 been worked out, using 

 four seed ears from six 

 selected rows from each 

 quarter of the breeding 

 plot. 



In the guide system, 

 for the sake of simplic- 

 ity, we use four seed 

 ears from each of the 

 first six even-numbered 

 rows in each quarter, 

 a selection which would 

 probably never occur in 

 actual practice. It will 

 be observed thatthe dam 

 seed ears for each quar- 

 ter are ears which grew 

 in the same quarter, 

 while the sire seed is 

 always brought from an- 

 other quarter. For the 

 first quarter (rows 1 to 

 24), sire ears are 

 brought from the fourth 

 quarter. For the second 

 quarter, sire seed is 

 brought from the third. 

 In each of these cases' 

 sire seed is carried diag- 

 onally across the breeding plot. For the third 

 quarter sire seed is brought from the first quarter, 

 and for the fourth, from the second, the sire seed 

 being carried lengthwise of the breeding plot in 

 these cases. 



It will also be observed that there is a definite 

 order of planting for "even years" and another 

 definite order for "odd years." Thus, in the first- 

 quarter, the even-numbered rows are planted in 

 ascending order with dam seed selected from rows 



