GRAFTING. 



226 



GRAFTING. 



hard wood or bone, at its lower end. A 

 bundle of course hemp, or worsted thread, 

 or of willow bark which has been softened 

 and rendered pliable by being soaked in 

 water, and some composition which shall 

 protect the graft from the atmosphere and 

 from rain, are also necessary, and these 

 complete the appliances necessary in graft- 

 ing. With regard to grafting wax, as these 

 compositions are generally called, there are 

 various preparations sold in the shops, 

 some of which are composed of ingredients 

 that are kept secret ; but many good gar- 

 deners are contented to use well-tempered 

 clay that is, clay of which the silicious or 

 calcareous particles have been washed out, 

 and pure clay only left. French gardeners 

 use a paste composed of 28 parts black 

 pitch, 28 parts Burgundy pitch, 16 parts 

 yellow wax, 14 parts tallow, and 14 

 parts yellow ochre. This mixture is applied 

 in a hot liquid state, but not so hot as to 

 affect the tissues of the trees ; it is laid 

 over the graft in coatings by means of 

 a brush, until sufficiently thick for the 

 purpose. 



Grafting and Budding, First 

 Principles of. 



Structure of Branch. Before any one 

 can hope to attain success in the opera- 

 tions known as grafting and budding, 

 it is necessary that he should have a 

 clear conception of the structure of the 

 part that is operated on, and of the func- 

 tions of the various parts of which the 

 stock and scion are composed at the point 

 of operation. When the stem or branch 

 of a tree is cut across transversely, it ex- 

 hibits a central mass of woody fibre within, 

 surrounded externally by a ring-like cover- 

 ing or coating, which we term the bark. 

 With regard to the woody portion in the 

 very centre is the pith or medulla, which 

 is supposed to possess the function of 

 nourishing the buds until they are suffi- 



ciently advanced in growth to obtain 

 nourishment for themselves. From the 

 pith the medullary rays extend themselves 

 through the woody fibre from centre tt 

 circumference, acting, according to Dr. 

 Lindley, " as braces to the woody and 

 vasifonn tissue of the wood," and convey- 

 ing "secreted matter horizontally from the 

 bark to the heart wood." These rays con- 

 nect the pith and the bark, and form the 

 medium of intercommunication between 

 the pith within and the buds without. 

 Broadly speaking, the sap ascends in 

 spring from the roots through the woody 

 fibre that is covered by the bark ; in 

 autumn, having been matured in the 

 leaves, it descends once again to the 

 roots through the bark, or passes hori- 

 zontally into the stem. 



Bark: its Tissues. The bark may be 

 at any time separated in a mass from the 

 woody stem, but this may be done more 

 readily in spring or autumn, when the sap 

 is ascending or descending. Looking at 

 it casually, it appears to be a coating of 

 homogeneous substance, rough and hard 

 without when exposed to the air, and 

 smooth and moist within at its contact 

 with the woody stem. The coating, how- 

 ever, which we call the bark, is com- 

 posed of tissues of widely different natures, 

 and is composed of different layers, each 

 of which possesses its especial function. 

 First comes the epidermis, corresponding 

 with the outer or scarf skin of the human 

 body, often called the epidermis also, 

 which is perishable and renewable. The 

 removal of this bark is in no way injurious 

 to the tree, and often it will split as the 

 tree increases in size, and come away 

 itself. Next to this outer coating is the 

 true bark, consisting of two layers known 

 respectively as the "outer" and "inner" 

 layers. Within this is another bark, called 

 the liber, or inner bark, composed of 

 bundles of woody fibre. In the lime or 



