48
Basic pruning cuts and
techniques
When growers have some background on basic
pruning practices and the fundamental reasons for
pruning Saskatoon berry plants, they can learn and
apply two standard pruning cuts and techniques.
The two necessary pruning cuts are
removal
and
heading
:
•
removal cuts: eliminate or thin vegetative growth
•
heading cuts: promote branching in close
proximity to the cut
Removal cuts
In general, removal or thinning cuts on Saskatoon
berry plants remove entire branches or growth back
to a main branch or the root crown. Removal cuts
should be made at the branch collar, a specialized
area of tissue that forms callous and scar tissue
most rapidly (see Figure 28).
Removing a branch from its base diverts the plant’s
resources into existing branches and allows greater
light penetration and more air movement. Removal
cuts are also made when a tree has too many
branches, which causes lower yield, poorly coloured
fruit and more disease and harvesting problems.
Lateral removal cuts on side branches are used to
thin the canopy and to remove other problems:
•
wide or low branching, which is unproductive
•
injured wood
•
narrow or split angles
•
diseased or insect-infested wood
A removal cut at ground level can be used to thin
the crown in the hedgerow or force a replacement
branch from the root crown. Growers should make
the cut as close to the ground as possible to prevent
infection by dieback disease organisms.
To avoid a replacement shoot where the cut is
made, the removal cut should be made as close to
the point of origin as possible; for example, remove
a sucker well below the ground level with a sharp
spade or disc, or expose the rhizome to the crown
for removal.
Besides making cuts to shape the shrub and
encourage healthy growth, growers may have to
make cuts to remove damaged or diseased wood. If
the branch appears diseased, make the cuts at least
30
cm (12 in.) below the diseased section.
Guidelines for making removal cuts:
•
Make cuts at a slight angle to allow any free water
to shed.
•
Make cuts flush to the main branch and as clean
as possible with the cutting blade against the
main branch.
•
Do not leave stubs for wood-boring insects or
disease organisms to enter.
•
Use a pruning compound only where fireblight or
other bacterial infections are present.
Figure 28. Removal cuts – on left: heading back
cuts; on right: thinning cuts.
When removing a large branch (too big for regular
secateurs), cut the branch back to a live branch or
to a trunk. To remove a large branch, make cuts in
three stages:
1.
First, make an undercut approximately 15 cm (6
in.) away from the trunk and about one-third of
the way into the branch. This undercut prevents
the next cut from tearing the bark.
2.
Next, make the top cut right through the upper
part of the branch about 5 cm (2 in.) beyond the
undercut (toward the branch tip). This cut greatly
reduces the weight of the branch.
3.
What is left is a 15 cm (6 in.) stub that should be
removed with a third cut. Because there is little
weight on it, the stub is easier to remove, and the
bark will not tear.