ADVENTITIOUS BUDS
“Buds such as we have been considering appear in the spring and then
spend the summer in gaining strength, after which they remain
stationary and as if wrapped in deep sleep all through the winter. The
following spring they wake up and grow into branches or blossom into
flowers. It is plainly to be seen that these dormant buds, as
arboriculture calls them in its picturesque language, must, in order to
withstand the summer heat and the winter’s cold, be clothed so as not
to be parched by the sun or killed by the frost. They are all in fact
covered with a wrapping of scales, and for that reason are called scaly
buds. Buds of this class are found in the lilac, chestnut, pear, apple,
cherry, poplar, and in fact nearly all the trees of our country.
But if a tree can wait and devote a whole year to the development of
its buds, which are clothed in a sheath of scales because of this
waiting, there are a multitude of plants that have only a limited time
at their disposal: they live only a year, and hence are called annuals.
Such are the potato, carrot, pumpkin, and a great many more. In a few
months or days they must hastily develop their buds. These, not having
to pass through the winter, are never enveloped in protecting scales:
they are naked buds. As soon as they appear they elongate, unfold their
leaves, and become branches taking part in the work of the whole. Very
soon, in the axils of their leaves, other buds make their appearance
and behave like their predecessors; that is to say, they develop
quickly into branches which in their turn produce other buds. And so on
indefinitely until winter puts a stop to this scaffold of branches and
kills the whole plant. Thus annuals ramify rapidly. In one year they
produce several generations of branches implanted one on another,
sometimes more, sometimes fewer, according to their species and their
degree of vigor. Their buds, designed for immediate development, are
always naked. On the contrary, those forms of vegetation that have a
long life, such as trees, ramify slowly; they have only one generation
of branches a year, and their buds, destined to live through the
winter, are scaly.
Certain examples of plant-life have both kinds of buds. Such, for
instance, are the peach-tree and the grape-vine. At the end of winter
the vine-shoot bears scaly buds lined with flock, and the peach
branches scaly buds coated with varnish. Both belong to the class of
dormant buds: they have slept all winter in their sheaths of fur and
scales. In the spring they develop into branches according to the
general rule; but at the same time there appear in the axils of the
leaves other buds without any protecting covering, and these develop
immediately into branches. Thus the grape-vine and the peach-tree beget
two generations in one year: the first, the issue of the scaly buds
that have endured the winter; the second, naked buds formed in the
spring and developing very soon after their formation. The branches
arising from these latter finally give birth to scaly buds, which sleep
through the winter and reproduce the same order of things the following
year.
“Both axillary and terminal buds are in the normal order of plant-life:
they appear in all forms of vegetation that live several years. But
when the plant is in danger, when by some accident the regular buds are
lacking or insufficient, others spring into being here and there at
haphazard, even on the root if necessary, to restore a languishing
vitality and put the plant once more in a flourishing condition. These
accidental buds are to the part of the plant above the ground what
adventitious roots are to the part below the ground: the menace of the
moment calls them into existence at any endangered point. The edges of
the wound caused by the lopping off of a branch, the part of a
tree-trunk constricted by a band, portions of the bark injured by
contusion, these are the points where they appear by preference. They
are called adventitious buds, but their structure does not differ from
that of normal buds.
“Adventitious buds lend themselves to valuable uses. Suppose a number
of young saplings to be planted at proper intervals in the ground. If
they are then left to themselves these saplings grow each into a single
trunk and form collectively a wood or forest. But it may be of
advantage to replace each of these single trunks by a group of several
trunks. In that case the young plantation is cut down to the level of
the ground, and around the edge of each cross-section there presently
spring a number of adventitious buds which shoot up into an equal
number of stems, so that each sapling that would have developed only
one trunk is transformed into a stump from which start numerous sprouts
or suckers, all of the same age and strength. Then instead of a wood or
forest we have a growth of underbrush, or a copse. When the suckers
have acquired the desired size, a fresh cutting back lays them low and
induces a still denser growth of shoots by multiplying the number of
wounds. It is thus that from a single stock, repeatedly cut back and as
often reinvigorated by the growth of adventitious buds, a quantity of
wood is obtained exceeding that produced by the free and solitary
development of one tree.
“Spared by the axe, the poplar rises in a majestic obelisk of verdure.
The willow, so ungraceful in appearance along the banks of our ditches,
with its shapeless top bristling with shoots sticking out in all
directions, is, in its natural state, a tree of rare elegance on
account of the suppleness of its branches and the fineness of its
foliage. Considered as a thing of beauty, it certainly has nothing to
gain by man’s interference with its mode of growth. But, alas,
productivity does not always go hand in hand with beauty; and if it is
desired to make these two trees, the poplar and the willow, produce a
great mass of branches and fire-wood, decapitation, repeated
periodically, transforms them into pollards, seamed with scars, gaping
with bleeding wounds, disfigured with bruises, but at the same time
contending against all this hard usage by a never-failing growth of
adventitious buds which constantly replace with increasing prodigality
the brushwood that has fallen victim to the axe.
“To finish the subject of adventitious buds—buds that persist in
multiplying even when the parent stock languishes, and that withstand
destruction until utter exhaustion has set in—let us recall for a
moment certain weeds such as dog’s-tooth grass, cock-spur grass, and
other grasses that are so hard to keep out of our garden paths unless
we do something more than merely rake the surface of the ground. You
may have taken infinite pains, we will say, to clean the paths, and
have left them immaculate, or at least you think so. But you are
mistaken. In a few days the grass has all come back in richer tufts
than ever. The reason is plain enough now: your raking simply cut back
the stems, leaving wounds that immediately covered themselves with
adventitious buds, which quickly sent up new stalks. Thus, instead of
destroying, you have multiplied. The only way to clear the ground of
weeds is to pull them up by the roots; that done, you may consider the
job well done.”