Q: Frank and June wrote to me about a large pine tree growing on a neighbor’s property that is leaning over their cabin in the local mountains. Their first choice is to remove the tree, but the neighbor said they can only top it.

So the question is, is it okay to top the tree?

A: As I have stated in other articles, it is never a good idea to top a tree unless you have a very good reason to do so. The safety of a cabin and the people in it would seem to be a good reason. A large tree of any species leaning over a home would at first glance seem to be a reasonable candidate for height reduction if it was otherwise healthy.

Topping is a method of trimming that radically removes a large portion of the top of the tree, usually eliminating onethird to onehalf of the upper canopy of the tree. This trimming process eliminates the natural form of a tree, and it never looks the same again.

If the tree has the ability to regenerate new branches, they’ll never look or grow the same as naturally occurring branches. The new growths, called water sprouts, aren’t well-attached to the tree trunk because they grow out of the side of the tree rather than with the tree as it naturally matures.

Some tree species, like eucalyptus, ash or poplar for example, have the ability to regenerate new growth after the tree is topped or even just trimmed. Most pines don’t do this. If you have a poplar tree and a pine tree growing side by side and you top them both, you’ll end up with dramatically different results in a short time. In one year the poplar would have many new branches up to 6 feet in height. The pine tree would probably look the same as when it was cut.

Trees in a natural forest setting, such as Big Bear, Arrowhead or the Sequoia National Forest, grow close together. Because of this, as the trees in a forest grow in height and thickness on their tops, they effectively reduce the sunlight filtering through to the ground.

Because of the reduction of sunlight to the lower portion of the trees, the lower branches of the trees die back. Because the top 25 percent of the branches are the only ones getting sunlight, those are usually the only live and green branches left on the tree.

If you looked closely at the pine tree in question, I’m sure it would become obvious that, if the tree is topped enough to help you with the leaning problem, there would be few or no green branches left on the tree. The tree will die.

If the neighbor agrees to let you top the tree, get him to also agree to its removal if the tree dies, because it will.

A dead tree leaning over your home can be a much worse problem than a live tree leaning over your house.

David Mortimer is a certified arborist with more than 30 years experience. E-mail questions to dmortimer@theacorn.com.