DEPTH OF PLANTING 



175 



farmer, then, should be careful not to bury the seeds too 

 deep nor to plant them too near the surface. He should 

 be especially careful also to have the seed bed warm, 

 moist, and mellow, so that the seed may germinate 

 quickly and shoot up rapidly, and so get through its crit- 

 ical stage in as short a 

 time as possible. 



124. Roughly speaking, 

 the depth at which a seed 

 should be planted depends 

 upon its size. Large 

 seeds need deep plant- 

 ing; small seeds require 

 shallow planting. It is 

 a common practice to 

 broadcast clover seeds 

 on the winter wheat in 

 early spring (Chapter 

 XXI), and trust to 

 spring rains or to the 

 freezing and thawing of 



the ground to cover 



. The one on the left was grown in sand ; 



them sufficiently. Let- the other> in waten 



tuce seeds are sown on 



the surface and pressed in slightly with a board. In one 

 series of experiments, wheat planted at the depth of one 

 half inch required eleven days to come up ; that planted 

 three inches deep required twenty days, and that planted 

 six inches, twenty-three days. Moreover, only one third of 

 the seeds planted under six inches of soil grew, while three 

 fourths of those planted under three inches of soil grew 

 and flourished. Such experiments have been made upon 

 many kinds of seeds, and it is worth while for farmers to 

 know the results. 



ROOTS OF WHEAT SEEDLINGS. 



