Agriculture Reference
In-Depth Information
Do not shorten back the tips of the
branches unless they are damaged. The tips
hold an apical bud (see page 3, 'Apical
buds') and their job is to extend the growth
of the tree, usually at the expense of the
axillary buds. This is exactly what is needed
to form a good stable branch structure for
your young tree, so leave the tips alone.
Confine any pruning to promote the central
leader and to remove or restrain competing
leaders or branches that have a greater
diameter than their parent branch. Such
branches will eventually destabilise the tree
so deal with them before they become a
problem. Look at the spacing of the
branches. Are they too close together,
prohibiting good branch attachment?
(See, for example, Figure 2.10). Allow for
30 to 60 cm between branches. Branches
growing at an angle to the trunk less than
45°
are also unstable, get rid of them now.
The only exception to this rule is with
fastigiate or very upright slender trees
that grow to create a column of foliage
like pencil pines or Lombardy poplars.
These trees will always have very narrow
branch angles.
of renovation or shape modification in the
future, see page 102, 'Renovating older trees
and shrubs', and Figures 5.23 to 5.33. If your
tree has particularly beautiful bark, you may
consider making more room under the tree
by raising the foliage canopy to show off this
feature (see Figure 4.54). Otherwise, just let
them be.
In the case of trees with multiple features,
such as
Lagerstroemia indica,
or crepe myrtle,
with fascinating bark
and
the potential for
huge flowers, the pruner must decide which
feature they want to emphasise. In order to
show off the silky muscled bark cladding the
tracery of branches, it is best to just let the
plant get on with it without intervention. The
plant will still flower if it is kept healthy, but
the size of bloom will be smaller.
If, however, the production of large
blooms is the priority (some may find
them gross), the branches should be cut
back by about a third annually after
f flowering (once it is established) to
encourage the new growth that will carry
the f flowers. This treatment keeps the
plant at the large shrub size and
therefore it functions as a shrub in the
garden design rather than a tree. Trees,
apart from maintenance for health, can
generally be left to develop by themselves.
Try to select and promote branches that
alternate around the trunk of the tree
vertically. This will ensure that the branches
will be balanced and not shade each other
(see Figures 1.8 and 1.9). Trees from
reputable nurseries should not have these
problems so pay that little bit extra for a tree
that does not need corrective pruning and
will therefore establish quickly.
Ornamentalshrubs
Shrubs are not statuesque except in the case
of topiary or dwarf conifers (see page 98).
They are largely purveyors of foliage, flowers,
stems, and sometimes fruits. The density and
magnitude of these features can easily be
enhanced by pruning.
Keep your tree healthy and the removal of
dead, diseased or crossed limbs is enough to
ensure its beauty. If you feel that it is in need
