PREPARATION AND PLANTING 195 



In November two bushels of seed corn were selected, one 

 bushel being placed in a corn crib and the other in a dry- 

 seed room. Germination was about equally good in both 

 cases, but the plants from the seed kept in the dry house 

 were stronger and the yield averaged five bushels more 

 per acre. 



GRADING SEED 



138. The corn planter cannot be adjusted to uniform 

 dropping of seed unless the kernels are uniform in size. 



Fig. 59. — Three rows on left from single ear of good seed corn. Three 

 rows on right from single ear of poor seed corn. 



Some growers sort the seed ears into two or three lots, 

 according to size of kernel. In some cases " sorters " 

 are used, consisting essentially of a pair of screens that 

 take out both the extra large and the extra small kernels. 



CALIBRATING THE PLANTER 



139. The dropping devices on planters are of three types, 

 known respectively as (1) round hole drop, (2) round hole 



