PROPAGATION BY MEANS OF CUTTINGS 97 



soft tip-cuttings of roots. It is probable, however, that all 

 plants can be multiplied by cuttings if properly treated. 



It often happens that one or two species of a closely defined 

 genus will propagate readily from cuttings while the other 

 species will not, so that the propagator comes to learn by ex- 

 perience that different treatment is profitable for very closely 

 related plants. For example, most of the viburnums are prop- 

 agated from layers in commercial establishments, but V . 

 tomentosum (often known as V. plicatum) is grown extensively 

 from cuttings. 



2. THE DIVERS KINDS OF CUTTINGS 



Cuttings are made from all parts of the plant. In its lowest 

 terms, cuttage is a division of the plant itself into two or more 

 nearly equal parts, as in the division of crowns of rhubarb, 

 dicentra and most other plants that tend to form broad masses 

 or stools. This species of cuttage is at times indistinguishable 

 from separation, as in the dividing of lily bulbs (page 57), and 

 at other times it is essentially the same as layerage, as in the 

 dividing of stools that have arisen from suckers and layers. 

 This breaking or cutting up of the plants into two or more 

 large parts that are already rooted is technically known as 

 division, and is discussed in Chapter III. It is only necessary, 

 in dividing plants, to see that one or more buds or shoots remain 

 on the portions, and these portions are then treated in the same 

 way as independent mature plants, or sometimes, when the 

 divisions are small and weak, they may be handled for a time 

 in a frame or forcing-house as ordinary cuttings. 



Cuttings proper may be divided into four general classes, 

 with respect to the part of the plant from which they are made : 

 1, of tubers; 2, of roots and rootstocks; 3, of stems; 4, of 

 leaves. All these forms of cuttings reproduce the given variety 

 with the same degree of certainty as do grafts or buds. 



