56 



CUTTAGE. 



upon the lower end, and it is commonly supposed that 

 this process must be well progressed before roots can form. 



But roots do not arise 

 from the callus itself, but 

 from the internal tissue, 

 and in many plants they 

 appear to bear no relation 

 to the callus in position. 

 In willows, for instance, 

 roots arise from the bark 

 at some distance from the 

 callus. Yet, as a matter 

 of practice, best results 

 are obtained from cal- 

 lused cuttings, particu- 

 larly if the cuttings are 

 made from mature wood, 

 but this is probably due 

 ■■to the fact that consider- 

 able time is required for 

 the formation of the ad- 

 ventitious buds which 

 give rise to the roots, 

 not to any connection 

 between the callusing 

 and rooting processes 

 themselves. 



Hard-wood cuttings 

 give better results when 

 kept dormant for some 

 time after they are cut. 

 They are usually made in 

 the fall, and stored dur- 

 ing the winter in sand, 

 sawdust or moss in a cool cellar, or buried in a sandy and 

 well-drained place. This, at least, is the practice with 

 hard-wood cuttings of deciduous plants, like currants, 



60. Heel cutting of cornus (xj^). 



