TREE-PRUNING
“Self-preservation is the first law of a tree’s life, and next to that
the preservation of its species, which is to be perpetuated by means of
seeds. All this is perfectly natural, for no posterity would be
possible to the tree unless its own existence were maintained in the
first place. Accordingly the tree lives first for itself, accomplishing
this object by covering itself with buds that develop into branches
covered with leaves. It is indeed on the leaves that the fundamental
principles of the plant’s life are based; it is in their substance
that, with the sun’s help, the descending sap is elaborated, this sap
being the nutritive fluid, the life-blood as it were, of the vegetable
organism. The propagation of the species comes next in importance. This
duty devolves on the flower-buds or those that blossom and produce
fruit, in the center of which are the seeds.
“Thus, left to its own impulses, a tree, if vigorous and enjoying
favorable conditions, at first uses all its sap in making buds for the
increase of its own woody structure; it covers itself with stout
branches and abundant foliage before making up its mind to blossom.
Later, when its limbs are strong and the ardor of growth begins to
abate, the flower-buds appear, but usually in small numbers because a
prodigal production of fruit causes rapid decline. Copious blossoming
comes only toward the latter part of life; a tree never blossoms better
than when it is about to die, as if, foreseeing its end, it strove
before succumbing to leave behind it a numerous progeny. A thriving
tree blossoms little or not at all; a sickly tree makes haste to
blossom. But it is to man’s interest that a tree should blossom and
bear fruit as early and as abundantly as possible; we demand from it
not the branches it would give us without our intervention, but baskets
of fruit induced by our care. From this struggle between the natural
tendencies of the tree and our own needs has sprung the practice of
pruning, or the art of manipulating fruit-trees so as to obtain from
them an abundant harvest.
“Here let us examine the general principles that are to guide us in the
practice of this art. The shape to be given the tree’s superstructure
of branches and foliage is the first question we must consider. This
shape is far from being unimportant; it is, on the contrary, very
important, since the circulation of the sap and the distribution of the
sun’s rays, essential conditions to plant-life, are strictly dependent
on it. If the tree is left free to develop by itself and to take its
natural form, the sap from the roots will, under the impetus of its
ascent, always seek by preference the highest points, where growth will
in consequence proceed with vigor, while the lower parts will languish
and die out for want of sufficient nourishment. If the branches are not
properly thinned the central ones, deprived of the sun’s vivifying
rays, will remain poor, puny, more or less blanched. On the other hand,
the tree ought to fill, as far as possible, the place assigned it, in
order that there may be no unproductive space.
“These conditions prescribe the tree’s shape. First of all, it should
be symmetrical, in order that the distribution of nourishment may be
even and no part of the tree be gorged with sap while another part is
deprived of it. Secondly, the sun’s rays should be allowed to penetrate
everywhere so as to ripen the fruit and facilitate in the foliage the
important work of sap-elaboration. To attain these different objects
custom has fixed upon three principal shapes: the trellis, the pyramid,
and the goblet. In trellis pruning the tree spreads its branches
symmetrically, right and left, against a wall. The wall serves it as
support and as shelter from the wind; it also gives the foliage and
fruit additional heat and light by reflecting the sun’s rays upon them.
When pruned to take the pyramid form, the tree has its branches so
trimmed as to decrease in length regularly from the base to the summit
and to remain far enough apart to admit the light to the center. The
whole forms a sugar-loaf, a cone, into the midst of which sun and air
enter freely. It is the shape most in accord with nature. Finally, the
goblet-shaped tree has a certain number of branches of equal vigor
disposed in a circle around a central space that remains empty and thus
receives its share of sunlight without hindrance.”