PROPAGATION BY GRAFTING, ETC. 285 



2. The acceleration of the fructification of plants, more especially of trees 

 and shrubs, which are naturally a number of years before they come into 

 flower. For example, a seedling apple, if grafted the second year on the 

 extremities of the branches of a full-grown apple-tree, or even on a stock 

 or young tree of five or six years' growth, will show flowers the third or 

 fourth year ; whereas, had it remained on its own root, it would probably 

 not have come into flower for ten or even twenty years. To obtain the same 

 result with climbers that flower only at their extremities, the tips of the 

 shoots of seedlings are taken off and grafted near the root ; and when these 

 have extended an inconvenient length, the tips are again taken off and re- 

 grafted ; and after the operation has been performed several times, the plant 

 at last produces flowers in a much shorter time than it otherwise would 

 have done, and in a comparatively limited space. 



3. To increase the vigour or the hardiness of delicate species or varieties, 

 by grafting them on robust stocks, such as the Mexican oaks on the com- 

 mon oak, the china roses on the common dog-rose, the double yellow rose 

 on the china or musk-rose, the Frontignan grape on the Syrian, &c. 



4. To dwarf or diminish the bulk of robust species, such as grafting the 

 pear on the quince or medlar, the apple on the doucin or paradise stock, the 

 cherry on the perfumed cherry, &c. 



5. To increase the fruitfulness and precocity of trees. The effects pro- 

 duced upon the growth and produce of a tree by grafting, Knight observes, 

 " are similar to those which occur when the descent of the sap is impeded 

 by a ligature, or by the destruction of a circle of bark. The disposition in 

 young trees to produce arid nourish blossom-buds and fruit is increased by 

 this apparent obstruction of the descending sap ; and the fruit of such young 

 trees ripens, I think, somewhat earlier than upon other young trees of the 

 same age, which grow upon stocks of their own species ; but the growth and 

 vigour of the tree, and its power to nourish a succession of heavy crops, are 

 diminished, apparently by the stagnation in the branches and stock of a 

 portion of that sap, which in a tree growing upon its own stem, or upon a 

 stock of its own species, would descend to nourish and promote the exten- 

 sion of the roots." 



6. To preserve varieties from degenerating, which are found to do so 

 when propagated by cuttings or layers, such as certain kinds of roses and 

 camellias. 



7- By choosing a stock suitable to the soil, to produce trees in situations 

 where they could not be grown if on their own roots ; for example, the 

 white beam-tree will grow in almost pure chalk, where no pear-tree would 

 live ; but grafted on the white beam-tree, the pear, on a chalky soil, will 

 thrive and produce fruit. 



8. To introduce several kinds on one kind. Thus one apple or pear 

 tree may be made to produce many different kinds of apple or pear ; one 

 camellia a great many varieties; one British oak, all the American oaks; and 

 even one Dahlia, several varieties of that flower. 



J). To render dioecious trees monoecious ; that is, when the tree consists 

 of only one sex, as in Negundo, some maples, the poplar, willow, Maclura, 

 Salisburia, c., to graft on it the other sex, by which means fruit may be 

 matured ; a knowledge given of both forms of the species, both forms intro- 

 duced into small arboretums ; and in the case of fruit-trees, such as the 

 pistacia, the necessity of planting males rendered no longer requisite. 



