Weekly Express-News Article

By Calvin R. Finch, PhD, SAWS Water Resources Director, and Horticulturist

Saturday, October 11, 2008

“Just Like New England”

            It won’t be long before we start seeing film clips and photos of autumn color in New England on the news.  You can experience fall color in the Hill Country at Lost Maples State Park and other similar sites.  If you work at it, your own landscape can have good fall color.  Now is the beginning of the best tree and shrub planting period.  If you are considering new plantings and like fall color, consider selecting trees that can provide that color.  The list is relatively large.

 

            If it is a larger tree that you want to consider, Texas Red Oak (also called Spanish Oak) is the best choice.  This is a very fast growing shade tree, but it is also a high quality tree.  High quality means it is long lived and is not prone to breakage or disease.  Texas red oak has a crown just a little more upright than live oak.  The branching is even attractive when the leaves have dropped.  Texas red oak reaches 50 or 60 feet tall and at least that wide so allow it plenty of room to grow.

 

            Red oaks are susceptible to oak wilt, but even in the worst case only three or four percent contract the disease.  To prevent oak wilt, paint all wounds immediately after they are made, especially in parts of the year when temperatures are mild.  Red oak foliage is red in the fall before the leaves drop.  The intensity of the color is determined by the genetics of the individual tree and the weather.  The best color seems to occur when the spring had adequate rain, the late summer is dry, and when cool night time temperatures are matched with warm daytime temperatures.

 

            Chinese pistache has good fall color.  Of all the trees described it probably has the most variation in the autumn color.  Most become a flat red color, but others will show orange or even yellow.  The same tree can vary in foliage color from year to year based on the weather.

 

            Chinese pistache is a fast growing tree in the league with Texas red oak.  It starts out being very vertical, with very little side branching, but eventually forms a very round disciplined crown.  Chinese pistache has the sexes on separate trees.  A female has berries every year that are favorites of the birds.  Pistache like well drained soil.  It can live and even prosper on heavy soils, but during wet years it will turn color in the spring or summer.  Homeowners become quite worried because of the garish leaf color, but the tree always seems to return to normal.

 

            Chinkapin oak grows moderately fast and has yellow fall color.  The species is more upright than Texas Red Oak and therefore less wide. It is just as tall as Texas red oak.  Chinkapin oak is in the white oak family so is not prone to have oak wilt.  It is fussier than Texas Red Oak about soil.  Chinkapin oak requires well drained soil.  It grows better in caliche soils than in the black clays. 

           

            Most of us think of summer blooms when we think of crepe myrtle.  We should also think of autumn color and decorative bark.  Many of the crepe myrtles have good red, orange or yellow leaf color beginning in October or November.  Your favorite nursery probably has a list posted that describes the ultimate size, flower color, leaf color, and bark characteristics of many of the crepe myrtle varieties on plantanswers.com.

 

            Chinese tallow does not rate high in very many tree categories, but it has attractive foliage color.  In the spring, the leaves are light green and in the fall it makes a good show with red orange bronzy foliage.  Chinese tallow will sometimes reach 30 feet tall and just as wide.  Now the bad news, Chinese tallow is a short-lived tree being susceptible to cold and sometimes drought.  It also is a notorious reseeding species.  The white seeds are carried by birds to fence rows and they also sprout in the lawn around the tree.  Limit your Chinese tallow planting to one or two trees and only if you are desperate for good autumn color. 

 

            Here are other shrubs and trees to consider for fall color.  The list was assembled by Mark Peterson, SAWS’ Conservation Horticulturist. 

 

            Rusty blackhaw (Viburnum rufidulum)  

            Bigtooth maple (Acer grandidentatum) 

            Blackjack oak (Q. marilandica)

            Blanco crabapple (Malus ioensis)

            Escarpment black cherry (Prunus serotina var eximia)

            Callery pear (Pyrus calleryana) – nonnative

            Mexican buckeye (Ugandia speciosa)

            Western soapberry (Sapindus drummondi)

            Fragrant sumac (Rhus aromatica)

            Shining sumac (Rhus copallina)

            Flameleaf sumac (Rhus lanceolata)

            American smoketree (Cotinus obovatus)