New estimates indicate it could be 500
years old, not 243.
Friday, August 25, 2006
By JAKE BATSELL Staff Writer and REX C. CURRY Special Contributor/ The Dallas Morning News
REX C.
CURRY/Special Contributor
Renee Burke, an urban forester, measures the circumference of
the tree in Bob Woodruff Park. It's 188.4 inches around.
Plano's oldest tree could have more than five centuries under
its trunk – at least twice the age previously believed.
Last month,
strong winds pried an enormous limb from the 90-foot-tall
Bicentennial Bur Oak, whose age had been estimated at 243 years.
Samples from the fallen limb suggest the tree may be older than
500 years, a local arborist and biology professor say.
REX C. CURRY/Special Contributor
Arborist Steve Houser dangles from Plano's Bicentennial Bur Oak as he
reattaches a lightning control system that was damaged last month when a
large limb broke off. That limb was used to get a new estimate of the
tree's age.
"In essence, it's the oldest
confirmed resident of the D-FW area," said Steve Houser, an arborist
who also chairs Dallas' Urban Forest Advisory Committee in Plano, asked Howard Arnott, a University of Texas at Arlington
biology professor, to examine the new samples.
Dr. Arnott found that the limb -- which had loomed at least 40
feet above the ground -- was 226 years old. That led him to
calculate that the tree has probably lived for more than 500 years.
Dr. Arnott stressed that his findings, which support earlier
estimates by Mr. Houser, are a "guesstimate." He concedes he is not
an expert in the precise science of tree-ring research, called
dendrochronology.
Still, everyone involved says the limb samples confirm that the
Bicentennial Tree is much older than 243.
"When you have a branch that's 226 years old, the base of it has
to be substantially older than that," Dr. Arnott said.
The bur oak may well be Collin County's oldest tree. But it's a
young whippersnapper compared with Methuselah, a bristlecone pine in
California's Inyo National Forest that has been around for at least
4,600 years.
While bur oaks are a resilient species, one rarely lasts 500
years, said Deborah Gangloff, executive director of American
Forests, a conservation group based in Washington, D.C.
"That's one lucky tree," Dr. Gangloff said. "It has not only
avoided the chainsaws and human problems, but also the weather."
It's unclear where the Plano tree ranks in longevity amo! ng
Texas oaks. The Texas Forest Service's Big Tree Registry crowns
champion trees in each species based on circumference, height and
crown spread -- but not age.
"We don't really keep track of how old trees are," said Pete
Smith, the registry's coordinator. "We're as amazed as everyone is
when we hear about a tree that's so old."
Austin's Treaty Oak is believed to be 500 or even 600 years old,
and the Goose Island Oak in Rockport on the Gulf Coast could be more
than 1,000.
Dating the Plano tree more definitively would require matching
samples from 20 trees in the same grove, said Rex Adams, a research
specialist with the University of Arizona.
Mr. Houser, whose company works with the city to preserve the
tree's health, said the latest revelations inspire a sense of
wonder.
"It holds the history of what occurred nearby for 500 years," he
said. "Think of what was going on here 500 years ago -- there were
buffalo and Indians, and that's it."
"It's kind of an honor and a privilege to be able to work on such
an ancient tree."
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