Seattle Children’s will move a giant maple tree from the hospital construction site this week, with plans to preserve and replant it. The tree is 50 feet tall, weighs 123,000 pounds (that’s more than 61 tons), is around 60 years old and is one of the largest trees the hospital plans to conserve in this process.

This is no ordinary move. It is tricky to transfer such a large, heavy and yet delicate tree. That’s why the hospital grounds team is working with arborists and experts who have years of experience to ensure the move goes well.

Here’s how a team of experts will move the tree:

  • They will first dig around the tree’s root ball. The root ball will be anywhere from 9 to 20 feet across and 5 to 8 feet deep.
  • They will wrap a galvanized basketing material (burlap or plastic sheeting layered on the inside and metal pipes) around the root ball to form a stable bottom. 
  • They will create a temporary and stable environment to house the tree. This holding area will be irrigated and the tree “healed in” and planted above ground by back filling between the tree with a special soil mix.
  • A crane will attach to the tree and root ball to move it into a holding area on the construction site where the tree will reside for nearly two years until it is transplanted in the new landscape. When possible, larger trees like this will be moved right into their final planting locations, to reduce the cost of a second move.

 Saving trees like the giant maple is one way Children’s is being ‘green’ and creating a living legacy of trees and plants.