MODES AND PRINCIPLES OP PROPAGATION. 47 



ing does not break the shoot and the cell injury starts the 

 process of healing sooner than by slitting. 



Fig. 17.— Layered brancli split to favor root formation. 

 (After Gofl.) 



Fig. 18. — Summer layering of shrubs. (After Bailey.) 



Summer layered shoots of a shrub are shown in Fig. 18. 

 The figure does not show the pegging down. If not 



