PACKING, PRUNING, PROTECTION, ETC. 31 



sen bulk, are all treated of at length by Loudon and others ; but all 

 seems to us summed up in the following, written by M. Dubreuil, in 

 France, and first published in this country in Barry's " Fruit Gar- 

 den." It is more especially applicable to training of trees in gardens, 

 than of standards in orchards. He says : 



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

 six general principles : 



" I. 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 distri- 

 buted in the different parts without any other aid than nature, be- 

 cause 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 nume- 

 rous, 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 happens that, unless great care be taken, the branches at the base 

 become feeble, and finally dry up, and the form intended to be ob- 

 tained disappears, 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 cer- 

 tain means, by the aid of which the natural direction of the sap can 

 be changed and directed towards the points where we wish to ob- 

 tain the most vigorous growth. To do this, we must arrest vegeta- 

 tion in the parts to which the sap is carried in too great abundance, 

 and, on the contrary, favor the parts that do not receive enough. 

 To accomplish this, the following means must be successively em- 

 ployed : 



" 1. 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 produced ; consequently, the sap is attracted therein 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 what- 

 ever form they may be conducted. 



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



