by Monika Maeckle
Big trees, or “champions” as they’re known in arborist parlance, exhibit the grandest, largest examples of their species in our state. Candidates are assigned points based on tree height, girth, diameter at breast height, then tallied. The “champions,” those that score the most points overall, make their way to the Big Tree Registry, to be lauded and admired.
Only three trees in Bexar County rank on the Big Tree Registry assembled by the Texas Forest Service. Two are native tree species (a Texas Mountain Laurel and a Tree-of-Heaven, to be featured at later dates) and one, a well-adapted interloper: the Mexican sycamore at Trinity University.
The Texas State Champion Mexican sycamore tree, Platanus Mexicana, rises from a drainage creek on the disc golf course at Trinity University campus, just south of Hildebrand near the Trinity jogging trail. The tree climbs to 70 feet and its canopy reaches 73 feet, sharing a space with a slightly less grand Mexican sycamore. Most impressive, the champion tree most likely has lived 35 years or less.
City Forester Michael Nentwich said the Mexican sycamore appears especially suited to our drought-prone climate. “This is a case where nonnatives outperform the native species,” said Nentwich. Foresters generally don’t recommend “foreigners,” but Nentwich strongly encourages planting this tree. “It seems to have a great adaptability to our particular climate.”
Like its native brethren, the Mexican sycamore boasts a distinctive shaggy bark and fuzzy white undersides on its maple-like leaves. The trunk of a mature specimen like this champion shows an uncanny resemblance to the camouflage pattern of hunting gear. Its leaf coloring waxes a bit more intense than native sycamores: darker green on the top of leaves, brighter white on the bottom.
Nentwich pointed out that this tree’s rapid growth can add up to “several feet a year.” The tree can live to be 75-100 years old. Once it reaches its genetic potential, it will gain no more height, but it’s trunk will continue to expand. Also: sycamores prune themselves, dropping their dead branches when limbs cease to be functional. This can be a blessing or a curse, depending on whether or not you or your car take a hit from a falling branch.
Mexican sycamores are not a major wildlife draw, but they do provide cover for birds and browsing for deer. The tree’s interesting seed pods start out in the spring as spiky green balls and mature to become golden brown orbs the size of ping-pong balls when ripe in the fall. Inside, seeds cluster around sycamore “fluff” which carries the seed with the wind, ensuring future generations. The fluff can cause allergic reactions, and the mischief-minded have been known to stuff sycamore fuzz down the shirts of unknowing slumber party guests causing a rude–and itchy–awakening.
The sweet smell of sycamore is a signature feature of this tree. Nentwich described it as “overwhelming sweetness.” Others have likened the fragrance to “sweet tea” and “human sweat.”
Planted in the mid 80s, Nentwich speculated that this champ is 30-35 years. The age of the tree at the time it was planted is unknown.
The Champion Mexican Sycamore Tree at Trinity University
Species: Platanus Mexicana Height: 70 feet
Canopy: 73 feet
Diameter at breast height: 37 inches
Circumference: 9 feet, 7 inches
Age: 30 – 35 years
Location: In the disc golf course on the Trinity University campus, just south of Hildebrand Ave. near Devine Rd. and Stadium Dr.
Get there by bus: Take Route 8, get off on stop F on Stadium Drive, head north on Stadium Drive until you reach Devine Road. Park is on your left.
Also known as: Ghost tree, since when it sheds its shaggy bark, it leaves a white trunk behind.
NOTES: Diameter at breast height, or DBH, is a standard of measuring tree diameter at four-and-a-half feet off the ground. Regarding the age of trees, arborists and foresters are reluctant to cite them. The only accurate way to determine a tree’s age is with an increment boring test, whereby a hollow drill bit is bored into the tree trunk. Very traumatic for the tree. Since soil and water availability determine tree growth, some trees grow huge in several decades while others live a century and can be much smaller. The tree’s temperament is also a factor.
In short, when it comes to determining tree ages, size doesn’t matter. We will cite educated guesses by certified arborists for the ages of featured trees, unless scientific or historical data are available.
Have a favorite heritage tree? Send us a photo, a story and we’ll consider it for inclusion to firstname.lastname@example.org.
More on San Antonio’s trees:
Monika Maeckle writes about gardening, butterflies, conservation and the Monarch butterfly migration at the Texas Butterfly Ranch. She covers nature in the urban environment for this website. You can reach her at email@example.com or follow her on Twitter @monikam.