Q. I was about to get my large oak trees trimmed and I thought I might get them removed instead. Is this a good idea?
A. That is a very general question and hard to answer without specific information about your own garden, but there are many important considerations before anyone removes a large tree. Let's look at the benefits that large shade trees provide in our climate.
We have intermittently heavy rainfall that can flood streets and basements and wash away vast amounts of topsoil. Look at the Tennessee River after a heavy rain and notice the brown color. Many of our properties are sloping and, even if you can hardly see it, unprotected soil washes away. Over time, gullies and bare spots appear.
Large trees are the first line of defense in soil protection. Their wide leaf canopy softens the impact of rain and their wide and deep root systems anchor soil. Scientists estimate that yearly leaf drop from deciduous trees the forest generates one inch of topsoil per 100 years.
In our own gardens, a mulch of deciduous leaves raked or blown into place in a wooded area and covered with a light layer of mulch or pine needles is an easy way to discourage weeds and protect soil. It looks attractive and adds to soil fertility. The root system of most large trees is as large as the branching system above ground. All that mass will hold your soil.
A large oak tree in full leaf in summer pumps out enough moisture on a hot day to lower ambient temperature 10 degrees. It cools the air for you and nearby plants and shrubs, reducing heat stress on them. The shade that the canopy creates can cool and protect your roof and house and reduce your cooling bills in summer. The fact that it loses its leaves in winter means that the winter sun can warm your house.
Real estate agents tell me that well-placed, healthy trees add value to properties.
So while large shade trees do require some maintenance, like leaf blowing, trimming of dead branches and perhaps the occasional watering, they are doing a job for you.
Consider tree removal carefully, since they can not be easily replaced. You should consider all the factors that may affect your property before you remove a healthy tree. The rotting underground mass of a large tree can create planting and drainage problems in the future, so removal is not a cure-all.
Contact Pat Lea at firstname.lastname@example.org.