AGRICULTURAL BOTANY 153 



fication before being planted. Alternate layers of 

 seeds and sand are placed in a shallow box and the box 

 is buried or set in a sheltered place covered with straw 

 or leaves to the depth of a foot. The object of this 

 is to soften the hard covering without stimulating 

 germination. Many nuts, like those of the walnut, 

 hickory, and peach, are allowed to freeze in order to crack 

 their hard shells. Such seeds are sometimes stratified 

 in boxes placed on the ground in sheltered places, or 

 they may be merely placed in a pile on the ground with 

 a light covering. Alternate freezing and thawing must 

 be prevented in stratification or the life of the seed will 

 become extinct. When once frozen, the seeds should 

 remain so until settled weather. Upon being removed 

 from stratification, they must be planted at once. 



Seed Planting. GofT gives four general rules for 

 planting seed : 



1. The soil in which seeds are to be planted should be 

 thoroughly crumbled, because the seeds must have access 

 to the oxygen of the air in order to germinate. 



2. Well-crumbled soil should be compactly pressed 

 about the seeds so that the seed case may come in contact 

 with the moist soil particles at many points and thus 

 absorb moisture. 



3. The soil should be moist, but not muddy, because 

 excess of water retards germination by restricting the 

 supply of oxygen and reducing the temperature of the 

 soil. 



4. Seeds should be planted no deeper than is necessary 

 to insure the proper degree of moisture, otherwise the 

 young plant may expend too much energy in reaching 

 the surface. 



Propagation by Rootstocks, Stolons, Suckers, Bulbs, 



