PACKING, PRUNING, PROTECTION, ETC. 33 



" The theory of the pruning of fruit trees rests on the following 

 six general principles : 



" 1. The vigor of a tree, subjected to pruning, depends, in a great 

 measure, on the equal distribution of sap in all its branches. 



" In fruit trees abandoned to themselves, the sap is equally dis- 

 tributed in the different parts without any other aid than nature, 

 because the tree assumes the form most in harmony with the natural 

 tendency of the sap.* 



" But in those submitted to pruning, it is different ; the forms im- 

 posed on them, such as espalier, pyramid, vase, &c., change, more or 

 less, the normal direction of the sap,' and prevent it from taking the 

 form proper to its species. Thus nearly all the forms given to trees 

 require the development of ramifications, more or less numerous, 

 and of greater or less dimensions at the base of the stem. And, as 

 the sap tends by preference towards the summit of the tree, it hap- 

 pens that, unless great care be taken, the branches at the base become 

 feeble, and finally dry up, and the form intended to be obtained, dis- 

 appears, to be replaced by the natural form, that is, a stem or a 

 trunk with a branching head. It is then indispensable, if we wish to 

 preserve the form we impose upon trees, to employ certain means, 

 by the aid of which the natural direction of the sap can be changed 

 and directed towards the points where we wish to obtain the most 

 vigorous growth. To do this, we must arrest vegetation in the parts 

 to which the sap is carried in too great abundance, and, on the con- 

 trary, favor the parts that do not receive enough. To accomplish 

 this, the following means must be successively employed : 



" I. Prune the branches of the most vigorous parts very short, and those 

 of the weak parts long. We know that the sap is attracted by the leaves. 

 The removal of a large number of wood-buds from the vigorous parts, 

 deprives these parts of the leaves which these buds would have pro- 

 duced ; consequently, the sap is attracted there in less quantities, and 

 the growth thereby diminished. The feeble parts being pruned long, 

 present a great number of buds, which produce a large surface of leaves, 

 and these attract the sap, and acquire a vigorous growth. This principle 

 holds good in all trees, under whatever form they may be conducted. 



" 2. Leave a large quantity of fruit on the strong part, and remove 

 the whole or greater part from the feeble. We know already that the 

 fruit has the property of attracting to it the sap from the roots, and 

 of employing it entirely to its own growth. The necessary result of 

 this is, what we are about to point out, viz., that all the sap which 

 arrives in the strong parts, will be absorbed by the fruit, and the 



* This is not in all cases true. Peach trees, we know, left to themselves, ex- 

 hibit a very striking example of the unequal distribution of the sap. The ends 

 of the branches attract nearly the whole, leaving the lateral shoots and lower 

 parts to die out. In other species, similar instances might be quoted, and, as a 

 general thing, the proposition is unsound, except in a comparative sense. 

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