LUTHER BURBANK 



increase in vigor of growth shown at the outset, 

 but it was continued at the same rate season after 

 season, where the plants were raised by division. 



The differences in the growth of the various 

 plants could be detected almost from the moment 

 when their tips appeared above the soil. 



But, of course, the selection involved very close 

 scrutiny, and I sometimes spent hours at a time 

 over a box containing perhaps ten thousand to 

 twenty-five thousand plants, selecting two or three 

 that outgrew all others. Here, as with the other 

 grasses, rapid growers in the boxes were almost 

 invariably rapid growers throughout. The seed 

 of the strongest growers was preserved, and the 

 experiment was carried forward with the expec- 

 tation of developing races of perennial sweet ver- 

 nal grasses that would not only show improved 

 quality of foliage, but an enormously enhanced 

 capacity for growth. 



The practical value of such an experiment as 

 this, from the standpoint of the agriculturist, will 

 be obvious. 



That such variations may occur among plants 

 from the same lot of seed gives a clew to the ob- 

 served differences of neighboring forage fields. 



It is clear that the diversities that are usually 

 ascribed to differences of soil may be due in part 

 to different strains of seed. The value of devel- 



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