Family Tree

by | Nov 1, 2008 | Conservation

EACH TIME Barbara and Gerry Gallivan sit outside and gaze at the massive 150-year-old bur oak (Quercus macrocarpa) that takes up much of their Oklahoma City backyard, they can’t help but feel a sense of awe.

“It’s amazing to us that this tree – which is the largest in Oklahoma City, measuring 65 feet high and 15 feet in circumference – was here even before Oklahoma became a state,” says Barbara. “There’s a good chance that American Indians camped underneath it, and it was here to see the Oklahoma land run.”

Last year the Gallivans successfully nominated the tree as an Oklahoma Centennial Witness tree through the state’s tree heritage program. “We don’t consider ourselves owners of the tree, but caretakers,” says Barbara. “We’re just glad that the builders of our house had the foresight to preserve it when they constructed our home in 1940, and we’re carrying on the tradition.”

Thanks to historic tree programs and increased media coverage of significant trees and their preservation, there is a groundswell of interest in preserving our nation’s historical trees. In addition to Oklahoma, states like Texas, Tennessee, Louisiana, Florida, California, Oregon, Washington, Vermont, Arkansas, Nebraska and Alabama run heritage programs that commemorate significant trees. Some of these programs even offer propagated offspring of historic trees for the home gardener.

“Trees have witnessed many historical events and played a significant part in forming our nation with their contribution to railroads and homebuilding,” says Mark Bays, state urban forestry coordinator for the Forestry Division of Oklahoma’s Department of Agriculture.

“Historic trees tell stories about their communities, and they are often an important tangible, living link to local history,” says Kathleen Wolf, a research social scientist at the University of Washington who specializes in environmental psychology, including the human response to city trees and urban green spaces. “Trees often have fascinating stories to tell.”

Of all plants, trees tend to be the most likely to hold historic significance because of their longevity and sheer presence in the landscape. Jennifer Rankin, program director for American Forests’ Historic Tree Program, says that historic trees are those that have shaded the lives of famous people or events. Based in Washington, D.C., American Forests is the nation’s oldest conservation organization.

Depending on its species and growing conditions, a tree can enjoy a long, eventful life. According to Rankin, some well-known, long-lived species that represent a number of historic trees include oak trees that can live up to 400 years and coast redwood (Sequoia sempervirens), which are located on the Pacific coast of North America. They can live for up to 2,200 years and are the tallest trees in the world. Even older are bristlecone pines (Pinus aristata) found in the American West and Southwest; the oldest of these is 4,767 years old. There are also trees with DNA that is up to 10,000 years old. In such cases, the original tree died, but a portion of tree root is still intact.

“As for the typical life-span of your basic, everyday tree, if they’re treated well, they generally last for at least three generations of humans, “ says Dr. Kim Coder, professor of tree healthcare at The Warnell School at the University of Georgia in Athens. “Trees and people are a lot alike,” he says. “If they have a great environment to grow up in, they’ll do wonderfully.”

Thanks to the science of dendrochronology, trees have a lot to say about what has gone on around them and can weave an interesting history. This discipline, which studies tree growth ring patterns, gives clues to earlier weather patterns and environmental conditions.

“Trees become a diary of the site they live on, mirroring past events like construction, storms and drought,” says Coder. “As perennials, they don’t remain static but expand their growth position year after year. Rather than healing, they seal off and grow on, which means they carry history in all of their bumps.”

Contrary to popular opinion, you don’t have to cut a tree down to study its growth rings, says Damon Waitt, senior botanist at the Wildflower Center. “You just remove a dowel-sized piece of the wood with a special drill bit, put it under a microscope, and start counting and measuring.”

Dendrochronology is an effective tool for understanding history, says board-certified master arborist and forester R.J. Laverne, who has worked in traditional forestry and is now manager of education and training at The Davey Tree Expert Company, based in Kent, Ohio. He recalls a 250-year-old dying oak about which he was consulted. “They wanted to know what happened,” he says. “It turns out that in the 1960s when they built an interstate close to the tree, they covered up one-third of its root system. When we examined a cross-section of the trunk and counted back to when the tree started suffering, it was the exact year of the construction.”

Beyond their scientific contributions, trees share a sense of history by simply being alive. “For whatever reason, there is a deep connection between the human spirit and trees,” says Laverne. “They are a reminder of the path that we all take as humans, and as such it’s easy to associate them with special events.”

Laverne’s company oversees the inventory of trees at the Arlington National Cemetery. “One huge, impressive post oak (Quercus stellata) really stands out because it sits in front of the site where John F. Kennedy is buried,” he says. “In another area lies a small grove of black locust trees (Robinia pseudoacacia) that holds a lot of historic significance. During the dark days of the Vietnam War, John F. Kennedy and his brother, Bobby, would sit in this grove of trees that looked out over the cemetery and back toward Washington, D.C., and make decisions for our country.”

Ted Bechtol is superintendent of the U.S. Capitol Grounds, Office of the Architect of the Capitol. He says there are more than 200 memorial or commemorative trees that have been planted by members of Congress over the years to recognize significant persons, occasions or events.

“There are a wide variety of trees, all with stories to tell,” says Bechtol. “A giant sequoia was planted to commemorate the 200th anniversary of the birth of Cherokee Chief Sequoyah, and the five crabapple trees on the East front lawn memorialize the five Sullivan brothers who all served on the U.S.S. Juneau and were lost in action in November 1942. Legend also has it that John F. Kennedy named a particular American elm (Ulmus americana) the “humility tree,” because its low hanging branches required senators approaching the Capitol to bow their heads as they walked under it.”

American Forests’ Historic Tree Program recognizes a wide variety of memorable trees by propagating and selling the offspring of trees related to famous people, places and events, from those planted by George Washington and Johnny Appleseed to Walt Disney and Martin Luther King. “Some of our more popular trees include the Gettysburg Address honeylocust (Gleditsia triacanthos), which stood behind Abraham Lincoln when he gave his famous speech; the “Moon” Sycamore (Platanus occidentalis), the seeds of which were taken into orbit by Astronaut Stuart Roosa on the Apollo XIV mission, and a southern magnolia tree grown from a seed that Lady Bird Johnson collected from the home of Andrew Jackson and planted at the Texas White House.

Oklahoma’s Centennial Witness Tree Program was created to commemorate historically significant trees throughout the state. “The purpose of the project was to find trees that ‘witnessed’ Oklahoma statehood in 1907 and locate the first trees planted by settlers,” says Bays. Owners of eligible trees are given certificates of commemoration. As an added bonus, Bays reports that some of the certificates have even saved trees that were slated for removal.

Perhaps Oklahoma’s most well-known historic tree is an 80-year-old American elm. Located in the heart of downtown Oklahoma City, it witnessed and survived one of the worst terrorist attacks on American soil. Before the April 1995 bombing that killed 168 people and injured hundreds, the tree provided ample shade in the parking lot with its huge canopy. After the blast, however, it was almost chopped down to recover pieces of evidence embedded in its bark. Thanks to the efforts of Bays and hundreds of citizens, the tree was spared and a successful plan to save it was launched.

“The tree was just 100 yards from where the bomb went off, but it survived the full force of the blast, and its remarkable recovery is truly a symbol of human resilience, renewal and hope,” says Bays. Every year now at the memorial service they hand out seedlings from the tree to the families and survivors.

One of Texas’ most well-known historic trees sits in a small park in Austin. Believed to be more than 500 years old, the Treaty Oak is the only survivor of a group of live oaks known as the “Council Oaks,” under which Stephen F. Austin signed the first boundary-line agreement with the Native Americans. In 1927, the tree was nominated into the American Forests’ Hall of Fame for Trees in Washington, D.C., but by 1937 it was in danger of being removed by its owner. The City of Austin then purchased it and dedicated the site as a city park. After being badly injured in 1989 by a troubled man who poisoned the tree in an attempt to kill the tree’s spirit and keep the woman he loved from another man, the Treaty Oak is healthy and growing again.

That some trees thrive and continue to grow despite the odds is sometimes a mystery, but there are things you can do to preserve your trees and see them live for hundreds of years. “One of the myths about big, old trees is that nothing can hurt them because they’ve been there so long,” cautions Coder. “The truth is that young trees are better able to react to environmental change. The older and bigger a tree gets, the less able it is to react to stress and strain and the more susceptible it will be to damage.”

Master gardener Julie Bawden Davis is an author of books about gardening.