172 



RAISING PLANTS FROM CUTTINGS. 



gitudinal incision down the cutting ; we then 

 insert • a wedge, to keep the wound open ; 

 without this precaution the two parts will 

 soon join, and the operation fail. The vipper 

 part of the incision ought to be nearly level 

 with the earth in the pot ; it sometimes hap- 

 pens that the roots issue at one and at the 

 same time from the slit and the base of the 

 cutting. 



Cuttings or Grafts upon Roots. — I 

 have often employed the following method of 

 striking plants which are difficult to multiply 



Fig. 50. 



by cuttings. The process may be slit-graft- 

 ing, as in fig. 50, or crown-grafting, as in fig. 

 51. The ligatures must be of worsted ; care 

 should be taken not to cover the upper part 

 of the roots of these grafts, or at least very 

 little. In such operations the cutting either 

 adheres to the root as an ordinary graft, and 

 pushes in the same way, or the root does no- 

 thing more than nourish and hold the branch 

 fast with which it is in contact, until it forces 

 it to send roots into the soil ; the cutting is 

 then on its own bottom, as we say. Tree 

 Pfeonies, Dahlias, &c., as everybody knows, 

 are multiplied in this manner. The case 

 where the branch joins itself to the root is 

 rare ; I have only observed it upon Grevillea, 

 Morus, Averrhoa ; there is ever; reason to 

 suppose that by the same means we might 

 obtain similar results on several other trees, 

 and I propose to try the experiment on plants 

 which cannot be multiplied by the ordinary 

 means. In this sort of multiplication it is 

 not necessary for the branch to be grafted on 

 the same root from whence we have taken it ; 

 but we may work on individuals of the same 

 kind, if we only take care that the root is in 

 proportion to the size of the plant. 



Fiar. 51. 



Striking Cuttings without Heat. — 

 For some time past I have tried to strike 

 without heat, hot-house 

 cuttings, which do not 

 like to root in tan. Cut- 

 tings of Bugainvillaea 

 spectabilis thus treated 

 have perfectly succeeded. 

 Stephanotis succeeded e- 

 qually well when struck 

 either in cold or heat. I 

 might conclude from this 

 that we may obtain the 

 same results in striking 

 cuttings whether they are 

 placed in heat or not ; rjy [ 

 but this is for time to de- ^\ i 

 termine. Moreover, cut- 

 tings exposed to the high 

 temperature of 36'^ centi- 

 grade (98^ Fahr.,) will 

 shoot with as much cer- 

 tainty as the same plants 

 placed in a green-house, 

 and subjected to a heat of only 7^, 8°, or 

 9° (45° to 50° Fahr.) In the last case, 

 cuttings will only take when the sun raises 

 the temperature to 25° or 30° (80° to 87'' 

 Fahr. ;) but then, as they have to bear a low 

 temperature at night, they will demand more 

 time to root than those which, placed in a 

 hot-house, are in the midst of an atmosphere 

 nearly equal day and night. Attempts of 

 this nature cannot be favorably tried in the 

 autumn or winter, the temperature being then 

 too low ; we shall have more chance of suc- 

 cess if the operation takes place in spring or 

 summer. 



In conclusion, let us observe, that so many 

 circumstances affect the method employed for 

 multiplication by cuttings that we cannot 

 foresee with any certainty whether we can 

 succeed in striking even the less difficult 

 plants. We must be constantly trying ex- 

 periments, for the conditions favorable to ve- 

 getation vary according to the strength of the 

 plant, and according to the temperature ; 

 moreover, the dryness or moisture of the at- 

 mosphere of the house, the earth which we 

 use, the light or shade to which cuttings are 

 exposed, favor or oppose their success. This, 

 however, seems to be shown by practice, that 

 the result is always more satisfactory in a 

 house entirely shaded, than in that in which 



