4 BULLETIN 1014, U. S. DEPARTMENT OF AGRICULTURE. 



directed more to a study of the effects upon growth and development 

 than to determining the most desirable date of seeding from the 

 standpoint of yield. Data have been obtained upon the rapidity of 

 germination, the number of days from seeding to emergence, emer- 

 gence to first silks, and emergence to ripening, the height of stalks, 

 the number of ears per plant, the average weight of ears, the average 

 yield per plant, and the number of suckers. 



The varieties of corn used in the experiments cover a wide range 

 in the length of the growing season required. No consistent effects 

 have been observed upon the number of ears per plant, the size of 

 ears, or the number of suckers. The data presented in the tables are 

 limited to the characters that seem to have been consistently affected. 



In 1915 24 varieties of corn were grown. The dates of seeding 

 were April 20, May 20, June 21, and July 22. The varieties in each 

 of the different seedings were sown in single rows 132 feet long and 

 3.3 feet apart on fairly uniform upland that had been in a mixed 

 clover and grass sod the previous year. The rate of seeding was four 

 kernels every 15 inches in the row for the first seedings and three 

 kernels for the later seedings. The stands were thinned to one plant 

 every 15 inches. The data obtained from this and succeeding ex- 

 periments are shown in Table 2. 



In 1916 22 varieties were grown. The dates of seeding were 

 April 20, May 20, and July 7. It was planned to make a third seeding 

 about June 20 and a fourth about July 20. The wet condition of 

 the land, however, made it necessary to delay the third seeding until 

 July 7, and because of this late date a fourth seeding was not made. 

 The different seedings were made in single rows 132 feet long and 3.3 

 feet apart on uniform reclaimed river land that had not been pre- 

 viously cropped. The rate of seeding was three kernels every 15 

 inches in the row. The stands were thinned to one plant every 

 15 inches. 



In 1917 19 varieties were grown. The dates of seeding were April 

 12, May 19, June 21, and July 16. The different seedings were made 

 in single rows 82.5 feet long and 3.3 feet apart on fairly uniform 

 upland where a crop of rye had been plowed under. The rye had 

 been preceded by soy beans. The seedings were made in hills 3.3 

 feet apart and the stands were thinned to two plants per hill. 



In 1918 14 varieties were grown. The dates of seeding were May 7, 

 May 24, June 20, and July 19. Owing to unfavorable weather the 

 earliest seeding was delayed beyond the date intended. The different 

 seedings were made in single rows 66 feet long and 3.3 feet apart on 

 well-drained, fertile, uniform upland that had been cropped to corn 

 the previous year. The stand of the smaller varieties was one plant 

 every 12 to 14 inches in the row and of the later, larger growing 

 varieties one plant every 16 to 18 inches. 



