2 BULLETIN 1157, U. S. DEPARTMENT OF AGRICULTURE. 
acteriof one ear per stalk has become more or less stabilized, whereas 
the character of weight of ear has remained in a more variable condi- 
tion. In the prolific type the number of ears per plant doubtless 
would be a more variable character than weight of ear. 
Although both the size of ear and the number of ears per stalk are 
limitedjby heredity, their expression will be determined largely by 
Fig. 1.— Typical single-ear plant of corn. 
Height, 11 feet. 
Fig. 2.— Typical single-ear plant of corn. Height, 6 feet : 
inches. Although not so tall, this plant was later i: 
maturing and produced a larger ear and apparently a 
much foliage as the plant shown in Figure 1. 
their environment. Other things being equal, the productiveness of 
the plants will be determined by their spacing. On land of uniform 
fertilitv the productiveness of the plant will tend to be in direct pro- 
portion to the area of land it occupies. In these experiments the 
spacings have provided a range of approximately 3 to 30 square feet 
per plant. The reaction of the varieties, as revealed in total yields. 
