EARLY DEVELOPMENT OF THE WHEAT PLANT 69 



Method: Follow the directions given for the study of 

 the early development of the corn plant in Exercise 15. 



Discussion: The roots of the wheat plant comprise 

 both a temporary and a permanent set. When the kernel 

 is placed in a warm moist soil it starts to grow, and sends 

 out a whorl of three small roots which supply the temporary 

 connection between the plant and the soil. After the leaves 

 unfold above ground a permanent set of roots develop about 

 an inch below the surface, regardless of the depth at which 

 the grain has been planted. These permanent roots increase 

 rapidly in length and develop into a fibrous root system 

 which serves the plant for the remainder of its life. The 

 greater part of the roots of the mature plant are to be found 

 in the surface fifteen to twenty inches of soil, but in loose 

 mellow soil some of the larger roots may go down five to six 

 feet. 



The depth of seeding for wheat will vary with the kind 

 of soil, amount of moisture and the fineness of the seed- 

 bed. Wheat may be seeded deeper in a sandy than in a 

 clay soil and it is desirable to sow deeper in a dry than in a 

 moist soil. Under average conditions it is desirable that 

 the seed be covered with about one inch of moist soil. 

 On uneven, cloddy ground it is necessary to put some of 

 the grains deeper than is usual in order to be sure that 

 all grains will be covered. 



