96 THE NURSERY-MANUAL 



grape cuttings are sometimes packed between layers of sand 

 in . a barrel, and the barrel is set under a forcing-house bench 

 where the temperature is about 50. Eight or ten inches of 

 sand is usually placed over the top layer. In this way, cut- 

 tings taken in winter or early spring may be callused before 

 planting time. 



It is a singular fact that the lower end of the cutting, as it 

 stood on the parent plant, produces roots, and the upper end 

 produces leaves and shoots, even if the cutting is inverted. 

 And if the cutting is divided into several parts, each part will 

 still exhibit this differentiation of function. This is true even 

 of root-cuttings, and of other cuttings that bear no buds. The 

 reasons for this localization of function are not clearly under- 

 stood, although the phenomenon has often been the subject 

 of study. On this fact probably depends the hastening of 

 the rooting process in inverted cuttings by the direct applica- 

 tion of heat to the bottoms (page 87), and it likewise indicates 

 that care must be taken to plant cuttings in approximately 

 their natural direction if straight and handsome plants 

 are desired. This remark applies particularly to horse- 

 radish "sets," for if these are placed wrong end up (even 

 though they are root-cuttings), the resulting root will be very 

 crooked. 



The particular method of making the cutting, and the treat- 

 ment to which it should be subjected, to cause it to strike 

 readily, must be determined for each species or genus. Some 

 plants, as many maples, can be propagated from wood two or 

 three years old, but in most cases the wood of the previous or 

 present season's growth is required. Nearly all soft and loose- 

 wooded plants grow readily from hardwood cuttings, while 

 those with dense wood are generally multiplied more easily 

 from soft or growing wood. Some plants, as oaks and nut- 

 trees, are propagated from cuttings of any description only 

 with difficulty, although the hickories grow rather freely from 



