Shade trees are nature's free cooling systems

Trees like the sugar maple pictured here provide excellent shade around the home.

We live in a forest. We call this the Piney Woods area. In fact, there are a multitude of other trees in our local forests, yards, parks and around our commercial buildings.

We take our trees, especially our shade trees, for granted. We drive past them in our cars on city and neighborhood streets. In July and August when we go to a parking lot, where is the first place we look to park? A shady spot or the spot closest to the door! And if we can find a shady spot close to the door, we’ve hit the jackpot. Where do we want to take a picnic at the park or have a nice stroll in the same park? In the shady areas, of course.

Shade trees are nature’s air conditioners. The science of shade has proven that if a shade tree has been correctly placed on the west or south side of a home, it can cut a homeowner's summertime electric bill by about $25 a year, the researchers found. That might appear to be small, but if thousands of homes in this state used this landscaping design, the overall savings of electricity could be substantial.

The key is the placement of the shade tree. Trees planted within 40 feet of the south side or within 60 feet of the west side of the house will generate about the same amount of energy savings. This is because of the way shadows fall at different times of the day. And we all know that different shade trees grow to different heights and spreads. This is a topic that should be researched by a homeowner before dropping a tree in the yard.

Sadly, due to poor planting techniques and being planted in the wrong place, the average tree only lasts eight years in a home’s landscape. Considering that most shade trees don’t even start to reach their potential until they are about 10 years old, this accounts for a lot of homeowner expense for removing a sick or poorly placed tree. Proper placement of your shade tree can do a lot for your home. In the summer, trees block 70 to 90 percent of the sun’s radiation on an intense Texas August day. When planted in the correct relation to your home, trees can reduce air conditioning demands by 10 to 30 percent.

For outdoor living, trees provide a "ceiling effect." A shade tree’s spreading branches create a canopy that forms a "ceiling" for an outdoor room. Some trees provide an especially inviting canopy. A sugar maple has a silver underlining to its leaves and can appear to be even more visually cooling because of the color. Oak trees can feel like they have a deeper, darkening shade because of their heavier limbs and their ability to muffle sounds.

The value of a shade tree can be different to different people. A grower, landscaper, arborist and naturalist may all have different ideas for the best shade trees. But the homeowner needs to think on some key elements before planting a new tree in their yard (front, back or sides), or replacing a tree.

First, do you have the room to plant a large shade tree, or do you need to find a smaller variety? Remember the dimensions we mentioned above. I’ve seen hundreds of home owners who plant a live oak less than 20 feet from their home and then wonder why, 10 years or so later, they are having to do heavy pruning or disfigure their once beautiful tree.

Second, where are the power lines? Nothing looks worse than a shaved-on-one-side or the flat-topped oak or elm tree because it was planted to close to the power or phone lines. These trees can not only de-value your home but can eventually become a hazard because of the uneven weight of the limbs on one side or the underside of the butchered tree.

Third, right-of-ways, driveways and sidewalks should all be considered when planting a shade tree. Again, homeowners think a tree planted close the driveway will provide great shade, but forget that those roots will expand and can eventually push up under the concrete. It is amazing what tree roots can move!

Finally, do you have the root spread area for the tree? By this, I mean is there enough space in the ground for the roots of the tree to spread out and receive all the nutrients it needs to stay healthy. Trees do not have a huge tap root as many people believe. Their support system is in the upper 2 feet of the soil. In fact, up to 90 percent of a tree’s root system can be in the top 2 feet of soil. So, for instance, a sycamore tree would need to be planted at least 12 to 20 feet from a concrete driveway, 60 feet from a concrete slab home, and no other tree of its same size and spread should be planted within at least 50 feet of it.

My Gramps used to say that if a squirrel didn’t have to take a flying leap to the next tree (he was talking about pecans in this instance), then it was too close to another tree. He understood that not only did the tree need root space, but air movement space as well. To this day, I watch the squirrels in our back yard and the woods beyond to see how close the canopies of our various oaks, wild olives, elms, Carolina laurelcherry, redbuds, magnolia and (not my favorite) sweetgums are to each other.

We have taken down over 17 trees on our large lot over a period of 16 years. Some were removed due to disease or threatening the home after hurricanes Rita and Ike, and the rest were to make room for our best trees. We identified the trees that add value to our shade, landscape, home and the plants around them. When I choose to remove a tree, it is after much thought. I walk around and look at how it will affect other trees and plants nearby. I check out the tree to be removed for one full year (if it is not diseased) to determine its shade range, bird habitat, other plants that would do better in that spot, and if there is another tree nearby that really needs that space.

A diversity of shade trees is preferred if you have the yard space. We have thinned trees to make sure our red and water oaks don’t have to compete for moisture. We have eliminated encroaching sweetgums from our beautiful sugar maples and elms so that they can spread to their full capacity. We have added a magnolia to provide a denser shade and give us that lovely aroma of the huge white blossoms in the spring. We are keeping an eye on 2 dead trees that currently provide homes for woodpeckers. These are unsightly but not close to the house and give us hours of fun watching the two families fuss at each other. We are noting trees that will need to be trimmed or felled as soon as the weather turns cool.

I am still trying to find a place to put a river birch. Not so much for the shade, but the wildly fun bark that this tree provides. I want different shade trees in my landscape so that each season there is something new to look at, and I want trees that I don’t have to fuss over. A diversity of trees, shade or otherwise, is recommended for a yard. This way if a disease or insect hits a particular type or variety of tree, a homeowner doesn’t lose their foundation pieces for their landscape.

Take a look at your shade trees. What do they do for the value of your home? Do they shade your house to their best advantage? Do they provide outdoor living space (for chairs, a hammock, a place for children to play)? Do they need to be trimmed, mulched or fed this fall to keep them healthy?

For help on understanding your shade trees, you can call the Walker County AgriLife Extension Office at (936) 435-2426. The Walker County Extension Office is also on Facebook. WalkerCoTxAgrilife has been established to provide updates and information to Walker County residents and landowners on a timely basis. The Walker County Master Gardeners are also on Facebook! Check out both of these Facebook pages and hit "like" to join.

Trending Video