The American Forests‘ online 2011 National Register of Big Trees has crowned 23 new Texas “big tree champions,” and one of them is the Dallas Arboretum’s Mexican-buckeye tree. The tree has an 11 foot circumference, is 14 feet tall, and has a “crown spread” of 14.5 feet. Average Mexican-buckeye trees are 8 to 12 feet tall, although in rare cases they can grow up to 30 feet, according to the University of Texas at Austin.
The American Forests started enumerating the biggest trees in the U.S in 1940, when Joseph Stern published an article in the September issue of the American Forests magazine titled “Let’s Find and Save the Biggest Trees.” Every year since then, the American Forests has kept a National Register of Big Trees. Now, the American Forests has more than 660 species on its list with trees in 45 states and the District of Columbia. 751 grand champion trees are listed, and this year.
American Forests uses an equation to determine what counts as a “big tree.” The equation is as follows: trunk circumference (inches) + height (feet) + ¼ average crown spread (feet) = total points.
“A nominee will replace a registered champion if it has more points,” the American Forests Big Tree FAQ page states. “When two trees have scores that fall within five points of each other, they are listed as co-champions. Champions listed in the registry must be re-measured every 10 years to maintain their champion status.”
So at least Mexican-buckeyes are bigger in Texas.