OTHER METHODS OF PROPAGATION 



329 



plant, but until it is established and independent, it must 

 depend upon the food stored up in the old tuber. It is evi- 

 dent, therefore, that the node, with its bud, must be in con- 

 nection with as much of the old tuber as possible, if the new 

 plants are to start rapidly and vigorously. The depth of 

 planting is different for early and late potatoes, being two or 

 three inches in the former case, and nearly twice as deep in 

 the latter. The character 

 of the soil and the nature 

 of the cultivation for this 

 very important crop will 

 be considered in another 

 connection. 



The same general prin- 

 ciples, applied with differ- 

 ent details, appear in prop- 

 agating by root-cuttings, 

 as in the case of raspber- 

 ries, sweet potatoes, etc., 

 or by leaf -cuttings, as in 

 the case of begonias. 



31 a. Layering. Propa- 

 gation by layering is really 

 only a modification of 

 propagation by cuttings, 

 the difference being that 



nodes Of the Stem are made FIG. 13. Layering a plant, as a rose or rasp- 



to strike root before they 



are separated from the parent plant. In case plants can be 

 propagated readily by cuttings, the less convenient method of 

 layering is not used. An outline of the method is as fol- 

 lows : In such plants as certain of the roses and raspberries, 

 a long and flexible young branch is bent down to the ground, 

 fastened in place, and the end carried up and held in an 

 upright position above ground (Fig. 13). The bent portion 



