PROPAGATION. 



230 



PROPAGATION. 



offsets are, in like manner, separated 

 from the parent plants and planted 

 by themselves. The artificial modes 

 of propagation are by layers, cuttings, 

 budding, and grafting; and all these 

 modes are founded on the principle, 

 that a bud is equivalent to a seed, 

 and, with certain exceptions, will, 

 when suitably treated, send down roots 

 from one extremity, and send up 

 shoots from the other. Sometimes 

 the bud can be separated from the 

 plant without any portion of its stem 

 or root, as in the case of bulb-bearing 

 stems ; but most generally, it is ne- 

 cessary to have a portion of the wood 

 or stem taken off along with the bud, 

 as in the case of propagating by cut- 

 tings, layers, grafting, &c. In the 

 case of budding, a smaller portion of 

 the wood or bark of the parent is re- 

 quired than in any other case, ex- 

 cepting that of propagating by bulbs, 

 which are nothing more than de- 

 tached self-supporting buds. As plants 

 have sometimes what are called ad- 

 ventitious or dormant buds, which 

 are called into activity by particular 

 circumstances, some plants may be 

 propagated by portions of the roots, 

 leaves, or branches, on which no bud 

 is apparent, as in the case of the roots 

 of the Rosacea? ; the leaves of some 

 species of Cardamine, Gloxinia, &c. 

 and the branches of the Willow. 

 In general those roots which abound 

 in milky juices, as Ailantus, Rhus, 

 C3talpa, Euphorbia, Nuttalia, Pa- 

 paver, Morus, Maclura, &c, will pro- 

 duce buds much readier than dry 

 roots, such as those of the Oak, of 

 which only one species, the Quercus 

 Tauzin, grows by cuttings of the roots. 

 In propagating by eyes or buds, some 

 florists strike their Pinks by redu- 

 cing the cutting, or piping as it is 

 called, to the topmost joint, and 

 cutting away all the leaves close 

 above the central bud ; the cuttings 

 are afterwards planted in a layer of 



sand on the top of a bed of rich com- 

 post, and covered with a hand-glass. 

 Any species of Dianthus, or any kind 

 of grass or reed, may be struck in the 

 same manner. Success is most cer- 

 tain in fine sunny weather, as it de- 

 pends on the excitement of the vital 

 energies of the bud ; and though it 

 has no leaves to nourish it, yet in 

 dry sunny weather it will strike 

 sooner than a piping with the leaves 

 left on, which grows best in dull 

 cloudy weather. In propagating by 

 leaves there is little that can be de- 

 pended on in a practical point of view ; 

 and therefore this mode of increasing 

 plants must be looked on more as a 

 curiosity than as any useful mode. 

 The propagating by cuttings much de- 

 pends on the manner in which they 

 are formed, and the state of the 

 weather : if this should be dull and 

 cloudy, cuttings with the leaves on 

 will succeed best ; but if it should be 

 dry and sunny, cuttings with few 

 leaves covered wdth a hand-glass so as 

 to exclude the air are to be preferred. 

 A cutting with only two or three 

 leaves, and these perhaps mutilated, 

 is similar to an eye or bud, and re- 

 quires to be excited ; while a cutting 

 with all its leaves on will perish from 

 excessive transpiration, if much ex- 

 cited. A great deal of the success of 

 cuttings depends on their being well 

 pressed by the medium in which they 

 are inserted ; they will grow squeezed 

 to the sides of the pot, and are found 

 to succeed best when pressed against 

 it. When planted in the open ground, 

 they should be firmly pressed at their 

 lower extremity ; as when pressed 

 towards their middle they will in 

 some cases strike root at that part of 

 the cutting, while all below it will 

 decay ; and in other cases the whole 

 cutting will rot. The depth to which 

 cuttings are inserted, depends upon 

 whether they are of the old or young 

 wood. If the former, tbey should 



