How Boise's giant sequoia will be moved
Work has begun to move Idaho’s largest sequoia tree from St. Luke’s at Avenue B and Jefferson Street to a new site at nearby Fort Boise Park.
The 104-year-old tree stands in the way of the hospital’s planned expansion. The hospital has hired Environmental Design Inc., a company whose expertise is moving large trees, to do the job.
On Wednesday, work began to dig a trench around the sequoia and prune its roots back to a 20- to 25-foot radius. A barrier will contain the roots. A specialized watering plan will help the roots heal in preparation for the actual move in the spring of 2017.
David Cox, co-founder of Environmental Design, said the company has developed a technique that involves building a steel platform to go under the tree once its roots are contained.
Then, inflatable tubes “like giant hot dogs” are slid under the platform. The tubes are inflated and the tree rises straight up, some 5 or 6 feet in the air, not unlike a wedding cake on a plate, Cox said.
As the platform moves, hauled by a back hoe, tubes in front are deflated. They’re then placed under the back end of the platform and reinflated. In this way, the platform rolls forward, slowly and smoothly, right over curbs and sidewalks and lawns.
“But you probably wouldn’t want to put your toe under it,” said Cox.
The process is similar to that used to launch ships. Cox expects moving the Boise tree, which will take place next spring, will take about two days.
The hospital will pay around $300,000 to move and care for the tree.
Experts are still working out exactly where the tree will be located at Fort Boise. Wherever it’s planted, it will feel like home. Soil from the site where the tree has grown for more than a century will be taken to the new site to replicate the environment as closely as possible, said Cox.
Environmental Design will install guide wires to hold the tree up. That’s mainly a precaution in the event of a freak wind storm, said Cox. The company will maintain the tree and help it get re-established until 2022.
So far, there are no plans to try to clone the tree from wood cuttings, or harvest pine cones to replant, but that would be a possibility for city foresters to consider, said Cox.
Once it’s moved, the tree will become property of the city.
A long and storied history
The tree is known as the Pittenger sequoia because its location was once the estate of Fred and Alice Pittenger, prominent Boiseans. The sequoia grew from a small cutting given to Fred Pittenger by the conservationist Emil Grandjean, one of Idaho’s first foresters, around 1912. The family gardener planted the cutting next to the Pittengers’ home.
Alice, a doctor who founded Camp Alice Pittenger, a Girl Scout camp still in operation in McCall, and the Children’s Home in Boise, died in 1953. Fred, also a doctor who served as Idaho surgeon general, died in 1964. New owners moved their house to Caldwell. The sequoia stayed behind.
The tree became a holiday attraction in the 1980s after the hospital began the tradition of stringing it with thousands of Christmas lights. Unfortunately, the decorations took a toll on the health of the tree. St. Luke’s consulted with horticulturists, removed the asphalt from around the sequoia’s trunk and stopped decorating it.
Eventually, tree experts were able to revitalize the tree by removing 11 feet from the top and bending a “leader” branch up to replace the treetop. The cure worked, though it did give the tree its distinctive Prussian helmet shape. The new tip is 15 feet and grew 4 inches this year.
Sequoias, more suited to regions such as Northern California, are relatively rare in the area. The Pittenger sequoia does have a local cousin, growing on the grounds of North Junior High at Fort and 13th streets.
The Statesman included the sequoia in its book “150 Boise Icons,” published in 2013 to mark Boise’s sesquicentennial.
A new sign posted on the fence surrounding the tree reads: “I’m moving! Come see me at my new home next year!” You can follow the progress until then at #BoiseSequoia on social media.
Tree’s vital stats
Height: 98 feet
Weight: About a million pounds
Circumference: 20 feet, 6 inches
Diameter 4 feet up: 77 inches
The Idaho Big Tree program, part of a national program that catalogs the largest trees in the U.S., has recognized the sequoia as the largest of its species in the state.