Perhaps the most important pruning cuts we make on trees are not the ones that
we do on big trees with large branches, but it's the ones we do on little trees
such as this when we're in our first, second, or third year of our pruning or
in reality what is the probably the first, or second, or third year of training.
What we're trying to do is develop the scaffold branches so the main structure of
the tree so that we ensure that we have a healthy strong attractive looking tree
for the life of its-- for the life of the tree. There's a couple important things
to keep in mind: one is that in some ways it's very much an art, and not only is it
an art but you have to kind of have a vision as to what you want this tree to
look like when you're finished. Along with that is it requires a lot of patience.
If this tree were a sculpture I could come along and prune it here or cut it here or
there and modify it as I see fit, but where it's a tree, we have a little
different situation because I make some cuts and then I have to wait until next
year to see how the tree grows in response to those cuts and then come back in on a
following year and make more cuts.
it points out a very important issue with trees and that is that they have to be
pruned every year. By pruning a tree such as this every year, we can respond to the
growth changes that occur on a yearly basis, and we can make the changes
or the corrections that we need to very small branches instead of having to come
in and cut some very large branches.
As we look at training a young tree, generally the rules we have are the same
we would with any other pruning situation. The first thing we want to do is get rid
of any diseased or dead or dying branches. If we have a dead stub, such as this one,
we can come in and remove that stub. If we see any disease it's a good opportunity to
remove it. You want to remove the dead stuff because they can be sites for the
entry of pathogens into the tree. The next step that we want to look at is, are there
any structural problems that we need to be aware of.
Are there narrow crotch angles? Branches that cross over? That rub? Any concerns
such as that. We have a problem here if you look at this tree, we've got a central
leader, right here, and ideally in order to keep this maple tree as healthy and
strong as possible we'd like to keep it as a central leader type tree.
One main branch going up and then lateral branches coming from that.
This situation though we have lateral branches that are in the process of
outgrowing that central leader.
If we allow those laterals to continue to be taller than the main leader then we get
a situation where we can have one or more co-dominant leaders, and we end up
with structural weaknesses, especially if we have narrow crotch angles such as we
can see right here. So the first thing we would want to do in this case is to get
rid of the potential weakness of that narrow crotch angle, probably this one
right here is a little bit too narrow as well and it also competes with that
central leader so we'll reduce it in size.
The other thing that we can do is to come in and head or tip back some of these
laterals so that again the central leader
remains the upper-most branch that we
would have here so that it retains apical dominance.
After we've taken care of the major structural problems, the next step that
we want to come in to is to start to look at the spacing of our scaffolding branches
now with this particular tree, or with any tree we don't want to take off more wood
than we actually have to. In general, the more leaf area you have the faster the
tree will grow and we've taken off about all that we can for this particular year.
In the future though, a couple decisions
that we'll have to make would concern, first of all, where do we want our bottom
branch to be? In this park, probably the lowest branches are this level or maybe
even a little higher. And so eventually we may end up removing all these branches.
That doesn't mean that we necessarily need to do that this year, we can leave it until
next year or the year following. And in fact if we can leave these branches on for
a few years it helps us to get a stronger trunk that grows in diameter more quickly
and rapidly than if we were to cut all of them off.
When we decide which scaffold branches we want to retain the other thing that's
important to keep in mind is that they should be spaced probably 8-12 inches
apart as a minimum, and they should be spaced radially or around the tree so that
we don't have all the branches one above another, but that we move around the
tree as we go on up.
Another thing that's important to point out is that when this tree was planted
last year, we didn't do any pruning at that time except to remove any broken
branches or any diseased branches that might have been present.
The reason for that is there have been studies that have shown that if we can
leave most of these terminal buds present then we tend to get better root growth
than if those are removed. If we remove them we tend to slow the growth down so
we like to leave as much as the growing
points as possible during that first season of growth.
And then the next year we come in and begin our pruning.
The pruning process again requires patience, it should take place over
several years, you cannot come in and do all the pruning in one year and
expect that tree to be pruned or trained for the rest of its life. It requires a
little bit of fine tuning each year as you go along and then you get a high quality
tree as compared to trying to do it all at once you just run into problems.