EXERCISE 11. TO SHOW THE PROPER DEPTH FOR 

 PLANTING 



Equipment: A case consisting of two panes of glass 

 placed about one-half inch apart and held in position by 

 means of a wooden frame. 



Method : Put an inch or two of soil in the bottom of the 

 glass case and then place a kernel of corn on top of the soil 

 close up to the glass. At the other end of the case a bean 

 may be planted in the same manner. Now put in an inch 

 of soil and again plant a kernel of corn and a bean, con- 

 tinuing the operation until the case is full of soil to within 

 an inch of the top. Water the soil thoroughly, cover the glass 

 sides with black cloth or paper to exclude the light and set 

 the case aside until the seeds have germinated. Other seeds 

 than corn and beans may be included in the exercise. 



Discussion : Seeds which are small and fine must not be 

 deeply covered with earth, for, if they are, the weak germ 

 which they contain will not be strong enough to reach the 

 light and air. Large seeds, however, which contain a con- 

 siderable quantity of stored material, as in the case of peas 

 and beans, may be planted quite deeply. In fact, peas, 

 which do not force the seed leaves out of the ground, should, 

 for best results, be planted from three to five inches in depth, 

 while beans, which have a different method of germination, 

 forcing their seed leaves out of the ground, should not be 

 planted too deeply, for, as in the case of soils which are clayey 



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