196 Principles of Plant Culture. 



Layering is a very reliable and expeditions method of 

 propagating many woody and herbaceous plants. 



350. Propagation by Division of the Crown of the 

 plant, which is practicable with many perennial herbs, 



as the rhubarb, dahlia, globe artichoke, etc., 

 though not strictly analogous to propagation 

 by stolons or layers, 

 may be considered 

 here. It consists in 

 taking up the plant, 

 preferably while dor- 

 mant, and cutting the 

 crown into two or 

 more parts, according 

 to its size or the num- 



FIG. 85. Layered branch of cur- her of plants desired, 

 rant, split to encourage the forma- 



tion of roots. an( j planting the divi- 



sions as separate plants. This method is applicable to 

 propagation for private use, rather than for sale pur- 

 poses. 



Propagation by approach grafting, although in order 

 here, is more readily treated with the other methods of 

 grafting (399). 



B PROPAGATION BY DETACHED PARTS. 



This comprises two different modes of propagation, 

 viz., by specialized buds and by sections of the plant. 



a Propagation by Specialized Buds. 



351. This includes propagation by bulbs, bulblets, 

 corms and tubers. It is in a sense intermediate be- 

 tween propagation by parts intact (346) and by cut- 



