OUTDOOR CORNER: TREE TOPING IS HARFUL PRACTICE

In recent weeks the issue of trees in the urban setting has pushed El Nino, the Hong Kong stock market and the White House guest list off the front page.

We have no problem with the need of the city to remove some trees. Sometimes for a variety of reasons the wrong tree is in the wrong place. Future planning that takes into account the requirements of utilities, concrete and trees will help avoid conflicts.

But as cool weather approaches lots of people take up their favorite outdoor sport -- tree topping. This is the practice of cutting back an older trees' limbs to an arbitrary point.

People do it for a variety of reasons. Some want a new flush of growth and a rounded look to the tree. Some do so because it is tradition.

One theory is that it started in Europe during a time when the trend was to have a manicured, formal landscape. Another story line is that it started with an early need for wood as home fuel. The tree outside the house could be topped every year as a source of home heat. Around the office some of us think this method beats driving all over the countryside looking for a place to cut tree tops out of a timber sale.

But let us be clear. Tree topping is harmful to the tree's health. It is also an unnecessary expense.

The exception is when the wrong tree is in the wrong place. For instance, when a tree top grows into a power line. Most people, if given the choice of a perfect tree or electric lights at night, will opt for the lights. So here the main priority is line clearance, not tree health.

Even in these cases some utility companies do practice target pruning as an alternative.

Do not confuse pruning with topping. Pruning, when done correctly, is beneficial and does at times provide crucial maintenance. Hire an experienced arborist to prune your trees -- do not top them.

Here are several good reasons not to top your tree:

* Starvation: Tree topping removes so much crown area that it upsets the tree's crown-root balance and reduces its ability to produce food.

* Insects and disease topping creates multiple wounds that are slow to callus over and they make a great entry point for pests.

* Weak limbs: New limbs sprout and grow rapidly from the topping cuts. They are poorly attached, decay easily and break even easier in high winds.

* Rapid growth: New sprouts grow rapidly. A tree that is topped to reduce its growth will grow back to where it started in a short time. Or it could get larger. Each species is programmed to reach a certain size and shape. So it has got to do what it has got to do or die trying.

* Cost: Topping is easier and quicker than taking the time to prune correctly. Just like everything else in life. And just like everything else in life, the quick and the cheap turns into the long and expensive. Once you start topping it must be carried out on regular basis to remove the brittle growth.

Contact your local Missouri Department of Conservation office for information on proper pruning methods. There is also information on proper tree planting, putting the right tree in the right spot to avoid future problems and the important steps of future tree care which we all forget once we get the thing planted.

There are also some copies of the book "Missouri Urban Trees" which describes 115 trees for the urban landscape.

Joe Garvey is an district forester with the Missouri Department of Conservation.