586 Reading-Course for Farmers. 



forty hills of each selection being planted. The row from each unit 

 should be plainly labeled or othen\'ise marked to avoid mixing the 

 pedigree. Treat this breeding-plot as described for the breeding-plot 

 in the second 3'ear, weigh up the product of each four-hill tuber-unit in 

 the same way to determine which unit of the second year's selections 

 has transmitted in greatest degree the tendency to yield heavily. Finally, 

 select again the best fifty tuber-units to continue the breeding, and 

 retain the good tubers of discarded units to plant a multiplication-plot 

 in the fourth year. 



In the third year, a multiplication-plot should be planted with the 

 good tubers from the discarded tuber-units of the breeding-plot of the 

 second year. In planting this plot, the grower can use any method of 

 cutting and planting the tubers which he thinks most desirable. This plot 

 should give enough seed to plant a fairly large plot in the fourth year. 



Continuing Selections in Fourth and Succeeding Years. 



In the fourth and succeeding years the selection should be conducted 

 by the same plan as outlined above. When this system is well under 

 way, it will be seen that each year the breeder is growing a small breed- 

 ing-plot, a larger multiplication-plot for seed and a general crop. 



Further considerations. As the selection progresses many of the 

 strains from the original fifty tuber-units will be entirely discarded. The 

 breeder must be continually watching for the appearance of a hea\y 

 yielding strain and if such a strain is discovered all of the further selec- 

 tions should be made from this strain. 



In advocating the selection of but fifty tuber-units and the planting 

 of ten tubers only from each select unit the writer has had in mind the 

 reduction of the work to a comparatively simple plan which would be 

 possible of execution by many growers. It would unquestionably be 

 better to handle larger numbers if the grower is so situated that he can 

 take the time for it. It is, however, better to use comparatively small 

 numbers carefully than to attempt to handle large numbers and find the 

 work too extensive, 



SECOND METHOD OF POTATO SELECTION 



Selection of seed tubers. The seed tubers to use in beginning the 

 selection should be selected as in the case of the first method, care being 

 taken to select nearly uniform sized tubers which would be considered 

 nearest to the ideal shape. Special attention should be given to getting 

 the correct shape, size, shallowness of eye, etc, and these tubers should 

 then be properly preserved, a factor which will be emphasized later. 



