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tliiii and pervious to the light; so that the internal parts of the 
tree may not be wholly shaded by the external parts ; the light 
should penetrate deeply into the tree, on every side ; but not 
any where through it. Wheu the pruner has judiciously exe- 
cuted his work, every part of the tree, internal as well as external 
will be productive of fruit. A tree, thus pruned, will not only 
produce more Iruit, but will also be able to support a much 
heavier load of it, without danger of being broken ; for 
any given weight will depress the branch, not simply in pro- 
portion to its quantity, but in the compound proportion of its 
quantity, and of its horizontal distance from the point of sus- 
pension ; by a mode of action similar to that of the weight on 
the beam of the steel-yard ; and hence a hundred and fifty 
pounds, suspended at one foot distance from the trunk, will 
distress the branch, which supports it, no more than ten pounds 
at fifteen feet distance would do. Every tree will therefore 
support a larger weight of fruit, without danger of being broken, 
in proportion as the parts of such weight are made to approach 
nearer to its centre. 
Each variety of the apple tree has its own peculiar form of 
grow th ; and this it will ultimately assume, in a considerable 
degree, in defiance of the art of the pruner. Something may 
nevertheless be done to correct whatever is defective. When the 
growth of any variety is w^eak and reclining, the principle stem 
should be ti’ained to a considerable height, before it be allowed 
to produce branches ; and if any of these take a horizontal, or 
pendent direction, they should be regularly taken oft’. One 
])i inciple leading stem should be encouraged almost to the sum- 
mit of the tree, to prevent a sudden division into two large boughs 
of nearly equal strength ; for the fork which these form is apt to 
divide and break, when the branches are loaded with fruit. All 
efforts to give the heads of young trees a round and regularly 
spreading form, whilst in the nursery, will be found injurious 
in the future stages of their growth. Large branches should 
rarely, or never be amputated. 
In the garden-culture of the apple, where the trees are re- 
tained as dwarfs or espaliers, the more vigorously growing kinds 
are often rendered unproductive by the excessive, though neces- 
sary, use of the pruning knife. I have always succeeded in 
making trees of this kind fruitful by digging them up, and 
