By Calvin R. Finch
Guest Columnist

This is the year to appreciate shade trees. Near record heat and very little rain has made shade even more valuable.

Autumn is the best time to plant a new shade tree, but now is a good time to consider it and select the tree that suits your purposes best.

Most of us want a shade tree that grows relatively fast, but is long lived. We also want a tree that is not plagued by insect pests or diseases, and importantly, it is capable of surviving our normal pattern of drought and excessive moisture.

There are aesthetic and size concerns as well. Most shade tree admirers like those trees best that have bold sturdy branching rather than a brushy look. It takes a tree that grows more than 35 feet tall to adequately shade a two-story house, but a smaller tree fits better in a small lot and compliments a smaller house better.

Live oaks are generally recognized as the premiere shade tree for the South Texas area. The sturdy crown with its horizontal branching and largely evergreen foliage sets the standard for other shade trees. Many live oaks grow to 50 feet tall, and nearly as wide. They tolerate all of our less than ideal soil conditions and prosper in our climate of extremes.

Live oaks are generally not thought of as a fast growing tree, but they live for hundreds of years. They do drop their leaves for a two-week period in early spring, are moderately susceptible to oak wilt and attract a few caterpillars in the spring, but still rate as the top shade tree. On some lots, a large live oak adds $20,000 or more to the value of the property.

Texas red oak has an equally attractive shape and branching pattern, and it grows at least 50 percent faster than the live oak. It also makes a very large tree.

Texas red oak is deciduous so leaf fall can be an issue every autumn. The leaves are great for mulch, however, and a deciduous tree is desirable if you want to open up the yard to more sunlight in the winter time. Texas red oaks often have good fall color.

Mexican white oak (Mon-terrey oak) is a very desirable shade tree. It has all the positive characteristics of the live oak and grows faster, at least one-third faster on most sites. Mexican white oak is also not susceptible to oak wilt in a landscape situation.

The species is, however, slightly more upright in growth habit than live oak and is more difficult to find at area nurseries than live oak. But it is worth a search.

Cedar elms are also deciduous, but they have very small leaves so they are less a problem in the autumn. All leaves can be left to decompose on the lawn, but cedar elm leaves disappear faster than red oaks or other large leafed shade trees.

Cedar elms make a large shade tree with strong branching that is more upright than live oak. Cedar elm has a drought survival strategy that annoys some gardeners. It will drop its leaves easily in a drought rather than fight to keep them fed and watered from the roots. Cedar elm seeds also find their way to fence lines and flower beds where seedlings appear every year.

Other good large shade trees to consider are chink apin oak, bur oak and Mexican sycamore.

For a smaller shade tree, consider Lacey oak. Lacey oak is from the white oak family so is not susceptible to oak wilt and it has the sturdy oak framework that is so attractive to most of us. The tree reaches about 25 feet tall on most sites. Lacey oak seems to grow at the same rate as live oak.

The leaves have a blue-gray hue that makes the tree interesting in the landscape. The leaves are live oak size and fall every autumn. They do not have any fall color.

Other good small shade trees to consider are ornamental pear, loquat, and Lacey oak.

Calvin R. Finch, Ph.D., is a horticulturist and the director of water resources for the San Antonio Water System.