Ugly truth: Over-pruning does lots of damage to trees

As I drive through Charleston and other places, I can’t help but notice a plague affecting many of the trees in lawns and landscapes. This plague isn’t spoken about much, but it leaves deformed, weakened and vulnerable trees in its wake. The sad thing is, this plague is completely avoidable.

I’m not talking about a fungal disease or an insect, though we have plenty of those. I’m talking about the man-made plague of severe over-pruning and tree topping. You’ve seen it too. You might even be guilty of it.

What I commonly see are trees cut way back to short branch stumps, hoping to grow new branches to hide their embarrassment and shame. This year that process seems to be slow or nonexistent thanks to our harsh winter. I’m seeing lots of trees in my neighborhood that would blush with shame if they could, embarrassed by their naked, mangled state.

This severe pruning technique has a name — it’s called pollarding. But just because it has a proper name doesn’t mean that it is proper. This severe treatment usually ends up creating more problems than it solves.

Now, I will tell you that this type of pruning is a pet peeve of mine. It is also something that most good horticulturists will roll their eyes at. Most trees require only light, sporadic pruning to maintain their shape or remove damaged limbs.

Start of a slow decline

First, let’s say that once you start pruning trees severely, such as pollarding or topping, which is even worse, there’s no way to go back. These treatments severely alter a tree’s growth habit, and you will have to maintain the pruning throughout the life of the tree. When you add it up, you’ll probably be investing thousands of dollars over the years.

Severe pruning also has negative effects on more than just your wallet. It can greatly impact the health and overall lifespan of the tree. The branches, trunk and roots of the tree all rely on food produced in the leaves to feed them. When you remove most of the canopy of a larger tree, you limit its ability to feed itself. The tree will become weaker and even some roots may die.

Weakening of the tree can also lead to other problems. Just like humans can get sick if their body is in a weakened state, weakness in trees can greatly increase the chances of disease infection and insect infestation. Leaving those long branch stumps also can increase this risk, as they can become an avenue of entry into the plant.

Poor form, unflattering shapes

Aside from the health risks posed with severe pruning, let’s face it — these trees aren’t all that attractive. Sure, most of them will eventually fill out with adventitious (coming from where branches don’t normally grow) branches, and will resemble a tree. But you can still see the underlying form even after they have leafed out.

This pruning also results in altered growth patterns in the branches. The ends of limbs and branches emit hormones that direct the growth of the rest branch. Without this signal, growth can go in almost any direction. What you usually see is a lot of vertical growth, or water spouts. These guys do little for the shape of the tree, and if the tree is a flowering one, they will not produce flowers. Plus, their attachment to the tree is much weaker and are much more susceptible to wind damage, especially if left to age.

Avoiding the problems

Since this is a man-made issue, the solution is simple. Just don’t do it! I know that it’s easier said than done. And I’m probably not going to convince everyone to avoid or stop this bad habit. But it’s important to know that this technique is not what we consider best practice. And be forewarned that your bad pruning job could end up being submitted to one of my favorite Facebook pages, “Crimes Against Horticulture” (check it out; it’s fun).

Most of this pruning occurs because the tree is either considered too tall or encroaches on structures, power lines or other trees. I would urge you, if you are planting new trees in your landscape, to consider both the height and the width of the tree. This information should be included on the tag or in the catalog. If not, do a little research before planting.

If you have a problem tree, I suggest looking at all of the options before beginning these severe pruning processes. Consider what changes that you could make to limit the issues. I would also suggest getting quotes to compare the repeated regular pruning over the lifespan of the tree to having it removed and replaced. While most people hate the thought of cutting down trees, it could be easier on the tree and your wallet in the long run.

– See more at: http://www.wvgazette.com/article/20140524/GZ05/140529746#sthash.XnybL4Vf.dpuf

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