Chapter Ten 

 PROPAGATION 



Seed-plants must be propagated, because they, Hke ani- 

 mals, get old and die. Other plants, which never produce 

 seeds, such as mosses and ferns, may be killed by animals, 

 fire, or cold but do not die of old age. They continually make 

 new growth at one end and die at the other end; however, 

 they too have the power to produce new plants from sexual 

 and asexual methods of reproduction. It is a simple matter 

 to dig the underground stem of a fern, as the bracken, where 

 the growing point is just ahead of the leaf, and several feet 

 back of the leaf the stem is dead, while farther back it is 

 decayed. In fact some of our living moss and fern plants 

 may be much older than our oldest trees. 



Propagation may be sexual, that is by seeds produced 

 through flowers, or asexual by a number of methods which 

 promote the development of new plants from root, stem, or 

 leaf sprouts. Other natural methods will suggest themselves 

 as we discuss artificial propagation. 



Sexual reproduction is the production through the seed of 

 a new plant which began when the male sex cell fused with 

 the female sex cell. Chapter 18 will make clear how a single 

 plant produces many combinations of its characteristics in its 

 sex cells. Furthermore, it is not necessary that the pollen 

 grain come from the same plant that bears the female part of 

 the flower but only from one of the same kind of plant (cross- 

 pollinated). Thus, plants grown from seeds will resemble 

 their parents but will vary widely in smaller details because 

 of the many combinations of their parents' characteristics, 

 just as sisters and brothers are all different. In many cases, 

 where quality is the result of an exact combination of char- 



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