228 MAIZE 



CHAP. 70 yards by 70 yards (an English acre), at one corner of the 

 v - field where the bulk of the same breed is grown. This should 

 be, preferably, on the side nearest the homestead or road, so 

 that the plot may be watched. This is called the breeding 

 plot (f 183). The rest of the field is planted with the best of 

 the seed which is not considered suitable for the breeding 

 plot. 



Second Years Selection. — The three outer rows of the breed- 

 ing plot (which have been most exposed to crossing with the 

 plants in the bulk field) are harvested with the bulk crop. 

 The rest of the breeding plot is harvested separately, and any 

 nubbins or undesirable ears are rigidly discarded. From the 

 remainder the twenty best ears are again selected and planted 

 in the breeding plot. The remainder are used for what is 

 known as the propagation plot, which may vary in size from 

 five to ten acres or more, according to the amount of seed 

 available. The propagation plot is planted around the breed- 

 ing plot, and forms a buffer between it and the bulk plot. 

 The best ears selected (Fig. 89) from the bulk plot are used 

 to plant the current season's bulk plot. 



Third Year's Selection. — -At harvest time the three outer 

 rows of the breeding plot are harvested with the propagation 

 plot, and the three outer rows of the propagation plot are thrown 

 in with the bulk crop. The remainder of the breeding plot is 

 harvested separately, and any nubbins and undesirable ears are 

 discarded ; from the balance the twenty best ears are again 

 selected for the next season's breeding plot, and the remainder 

 are used to plant the propagation plot. 



The remainder of the propagation plot is harvested sepa- 

 rately ; nubbins and objectionable ears are discarded, and the 

 best of the balance is used to plant the bulk fields. 



Thus in the third and subsequent years the bulk fields are 

 supplied entirely from twice selected seed from the propagation 

 plot, while the propagation plot is itself supplied from the 

 breeding plot. 



In the fourth and subsequent years the work is continued 

 as in the third year; it must always be maintained, for though 

 there is a maximum beyond which " selection " alone cannot 

 carry one, deterioration takes place with remarkable rapidity 

 when selection ceases. 



