PKOPAGATION. 



231 



Tig. 296.— Layering by Circumposition. 



soil or compost is carried up, and in various 

 ways made to surround it. Pots as shown in 

 Fig. 296, or boxes made of slate, not being 

 porous like those of earthenware, would be 

 proper for this mode 

 of propagation. An 

 excellent contrivance 

 for this purpose is a 

 piece of thin tin-plate, 

 folded in the shape of 

 a funnel, and fixed 

 with clips round the 

 branch. It is filled 

 with moss or soil, 

 which is kept moist 

 by a drip from a 

 bottle of water fixed 

 above it, with the 

 cork pierced so that 

 the water can drip 

 slowly on to the 

 branch operated upon. 

 The Chinese ring a 

 part of a branch and 



then fasten round it a large ball of clay and 

 cow-dung, well incorporated, and similar to our 

 grafting clay, the whole being maintained in a 

 moist state by means of a vessel placed above it 

 and kept supplied with water, of which enough 

 is allowed to escape by a small hole at the 

 bottom. This method was practised in Britain 

 more than one hundred and fifty years ago. 

 Eeid, in his Scots Gardener, published in 1721, 

 after describing the mode of propagation by 

 circumposition, says : — " I have effected this 

 with clay and cow's dung, well mixed (after part 

 of the bark has been taken off round), and 

 wrapped about with a double or triple swad- 

 dling of straw or hay ropes." 



VII. — Propagation by Cuttings. 



A cutting is any rootless portion of a plant 

 other than the seeds that is removed and utilized 

 for purposes of propagation — whether it be a 

 branch, a portion of a branch, a leaf, or even 

 a fleshy root. When properly selected, duly 

 prepared, and placed under favourable circum- 

 stances, the cutting emits roots and grows, and 

 thus an individual plant may be increased to an 

 extent corresponding to the number of parts 

 eligible for cuttings which the plant can afford 

 at once or in succession. With the exception of 

 seeds this is the commonest of all methods of 

 propagation, and, as a general rule, by far the 

 most expeditious and satisfactory. The special 



advantages of propagation by cuttings as com- 

 pared with that by seeds is that by the former 

 we reproduce exactly all the peculiarities of the 

 parent as completely as if the cutting was still a 

 part of that parent, whereas by the latter, viz. 

 seeds, the special characters of the parent may 

 not, generally will not, be reproduced. 



If a plant be cut off by the surface of the 

 ground, and consequently be deprived of its 

 nourishment from the roots, it will, if kept in a 

 moist condition, notwithstanding, remain alive, 

 for a time at any rate, and its buds will continue 

 to attract the sap from the vessels with which 

 they are connected, and will expand into leaves. 

 These, as well as the others with which the cut- 

 ting may be already furnished, will continue to 

 perform their functions nearly as before the 

 separation of the plants from its roots, that is 

 to say, they will elaborate the sap if there is a 

 constant supply of moisture from below, or if 

 the atmosphere about them is kept saturated so 

 that evaporation is prevented. 



As long as the leaves have a supply of sap 

 they will continue to elaborate and convert it 

 into organic nourishing matter, which is ex- 

 pended in the upward growth of branches and 

 in the formation of new wood in every part of 

 the plant down to the remotest rootlets. If, 

 then, the connection between the roots and the 

 top be severed, that matter which would have 

 gone to the formation of roots is arrested in its 

 course; it therefore accumulates at the lowest 

 point, and, if other conditions be favourable, 

 will in time form a new system of roots. Some 

 plants are so constituted as to be able to do this 

 readily, others do it very slowly and only under 

 very favourable circumstances, and others appear 

 to be incapable of doing it. Success depends, 

 however, upon various circumstances, to which 

 it is necessary to advert. The cuttings require 

 to be of a certain age and size; to be inserted 

 at the proper season, and in a suitable medium; 

 and afterwards kept in a well-regulated con- 

 dition as regards heat, moisture, and light. 



Selection. — Cuttings should be taken, if pos- 

 sible, only from healthy plants, and from parts 

 of these which are not in a weakly state; for if 

 the shoots or branches of a plant are not in a 

 condition to make a fair growth with a supply 

 of nourishment from the roots of the parent 

 plant, they cannot, when made into cuttings, be 

 expected to possess sufficient energy to develop 

 roots. At the same time, excessively vigorous 

 shoots, accustomed to receive a very abundant 

 supply of nourishment, are not so well able to 

 keep alive, when deprived of that supply, as 



