Urban BIG Trees
By Tony Zeli
Did you know? Arborists and tree enthusiasts have been working for the last 80 years on cataloging the largest trees in the nation. Known affectionately as the Big Trees List, it’s a national registry of the biggest trees in America. It’s the national Forest Service’s way of recognizing the importance of trees – from providing shade and shelter to helping to clean the air and water. Maine also has its own state registry with about 170 trees listed. And if you know of a big tree, you might be able to get it recognized.
The BIGGEST of the Big Trees
The goal for any proud big tree community is to record one that makes the Champion Trees National Register, listing the largest trees of their kind. And the champion of champion trees is a national treasure, the Sequoia named General Sherman in California’s Sequoia National Park. It’s been the crowned king since the registry’s inception in 1940. In fact, it’s the world’s largest tree measured by volume. It’s 275 feet tall and over 36 feet in diameter at its base.
To put that in perspective, all 16 stories of Franklin Towers, the tallest building in Portland, add up to a mere 175 feet. The tallest building in Maine is the former St. Patrick’s Church in Lewiston, which measures a respectable 220 feet to the tippy top of its taller spire. The champion Sequoia overcomes that spire by a whopping 55 feet!
Local Big Trees
Portland claims at least ten trees on Maine’s registry. Several of these are within the newly created heritage tree district. The heritage tree ordinance aims to protect large trees on private property in historic districts that are at least 24” in diameter at breast height for shade trees (12” in diameter for ornamental trees). A few Big Trees are in Deering Oaks park, the largest being a Pin Oak, 140 inches in circumference and 83 feet tall. Also, you’ll find a huge Siberian Elm, an eminent Green Ash, and according to Portland City Arborist Jeff Tarling a dozen or so White Oaks that don’t quite make the list, but are so close, and still quite impressive.
Two other Portland Big Trees are in Parkside at the Sacred Heart Church, where the biggest Dawn Redwood, or Metasequoia, is over 80 feet tall and the Kousa Dogwood is the Maine State record, with 32-inch diameter and standing 30 feet tall. Also, Portland High School is home to the largest Florida Dogwood.
Nominations Open for the Big Trees List
To nominate a tree for Maine’s Register of Big Trees, you need to measure the tree’s trunk circumference, vertical height, and average crown spread – the average width of the tree’s foliage and branches. The measurements are added together using a simple formula to come up with a point value. The Pin Oak in Deering Oaks Park has a total score of 248. Compare with the largest tree on the list, an 89-foot tall Silver Maple in Leeds, with a 75-foot canopy and 316-inch circumference for a total of 424 points.
Sure, it’s ultimately a measuring contest. But what a massive measuring contest it is!
To learn more or to obtain a Big Tree Submission Form, visit https://www.maine.gov/dacf/mfs/policy_management/project_canopy/programs/big_trees.html.