A Chinese elm is inconspicuous among the evergreen wax myrtle and nandina, along the fencerow of a tennis court in Overton Park -- less 20 feet tall, holding leaves until late, with a smooth bark of mottled orange and brown. But since I first noticed it there, I can't help but look every time I pass, nearly every day.
My interest in this little tree (the species native to Asia) is tied to the tension between admiration of its beauty and comfortable urban fit and apprehension of its potential to become a weed, springing up like dandelions and crowding native species.
Maybe the tree came up on its own, because the species is commonly planted around Fort Worth and is known to be self-propagating (euphemism for "invasive"?) in neighboring states. But I'm guessing that it was planted there, probably soon after the tennis court was constructed in the 70s, by someone who maybe envisioned it growing faster and becoming larger.
Chinese elm is recommended and sold as a landscape tree -- it's resistant to insect attack, Dutch elm disease, and air pollution, and in Fort Worth it's planted in yards as well as plazas and patios. On the other hand, it has escaped plantings and become invasive in Australia and South America -- perhaps also to "go wild" in the USA. Plenty of literature gives advice on "control and management" of this species, describing techniques of eradication. A quandary, yes?
Guy Nesom
November 2007
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Ulmus parvifolia Jacquin (= Ulmus chinensis Persoon) Chinese Elm, Lacebark Elm
Native to China, Japan, North Korea, and Vietnam; known to be self-propagating in South America, Europe, Australia, and various places in North America, including Oklahoma, Louisiana, Kansas, New Mexico, Arizona, California, Nevada, Kentucky, West Virginia and Atlantic coast states
Form: small trees 20-70 feet tall with a spreading crown of fine branches.
Bark: smooth with jigsaw-like puzzle pieces mottled green, gray and orange; the trunk may become shallowly fluted.
Leaves: alternate, mostly about 1 1/2 inches long, with toothed edges; leaf bases conspicuously asymmetric; summer leaves are dark, shiny green -- fall colors appear late, with a mixture of yellow and orange.
Flowers: inconspicuous, light green in small tight clusters in leaf axils, appearing in September to early October; wind-pollinated.
Additional information and photos:
* Virginia Tech - Dept. of Forestry
* Ohio State University - Horticultural and Crop Science
* North Carolina State University - College of Agriculture and Life Sciences
* University of Georgia and USDA Forest Service - Forestry Images
Many other elms grow nearby in Overton Park and in Fort Worth. There are abundant large trees of the native cedar elm (Ulmus crassifolia), most if not all in the park having grown without being planted, but seedlings and saplings are allowed there no longer, because of the relentless mowing of every nook and cranny. Slippery elm (Ulmus rubra) and American elm (Ulmus americana) both grow along the creek.
Stephen Jay Gould essay about the rationale for preferring native species: An evolutionary perspective on strengths, fallacies, and confusions in the concept of native plants (Arnoldia 58(1): 2–10. 1998). Also see Conservation Topics and Controversies (BRIT website).
