CHAPTER HI 

 PROPAGATION BT CUTTINGS 



A CUTTING is a detached portion of a stem which, when 

 inserted in sand, soil,, water, or some other favorable 

 medium,, will produce roots. It is not a natural means of 

 multiplication, but is used to propagate plants that do not 

 come true to seed, or those that do not propagate more 

 readily in some other manner. Nearly all plants may be 

 propagated by cuttings, but some species and even some 

 varieties of the same species may be multiplied more 

 readily than others by this means. 



That a cutting may develop a new plant, it must possess 

 the following essentials: (i) a certain amount of healthy 

 tissue, (2) stored food, and (3) a growing point. The 

 portions of the plant selected for cuttings are, therefore, 

 the younger matured growths of the roots or steins con- 

 taining one or more buds. 



External Requirements. In order that cuttings may 

 callus and send out roots readily, certain external condi- 

 tions must be supplied and maintained. The principal 

 conditions are temperature, moisture, and soil- 

 Temperature - It is important that the temperature 

 be carefully controlled. Heat stimulates plant growth, 

 hence in the propagation of plants by cuttings, it is es- 

 pecially desirable to supply bottom heat that the soil may 

 be warmer than the air. This tends to stimulate the forma- 

 tion of roots, and checks the growth of the foliage until 



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