Why Are Big Trees So Important?
Big trees fascinate people because they catch their attention. At first sight, people are often amazed by big trees’ size and beauty. These trees help spur the imagination: How did this tree get here? If this tree could talk, what has it seen? Why did this particular tree live so long? Big trees are a minority in any forest and they grace our landscape with nobility.
Visit the photo gallery of some of Vermont's largest trees.
History of Vermont's Big Tree List
In 1972, a list of Vermont’s largest trees was assembled under the guidance of Jeff Freeman, a now-retired professor of Castleton State College in Castleton, Vermont. The list contained 27 of the largest then-known trees, listing diameter only. The later lists of 1977 and 1982 expanded the list to 75 and 81 species, respectively. Then, in 1990 the Vermont list was expanded to 91 species and updated to follow the American Forests (AF) system in use since 1940. The AF formula uses distinguishing criteria: circumference, tree height, and crown spread. The AF National Register lists 734 species of Big Trees and is available electronically. Today there are 110 species and varieties on Vermont’s current list, and they range in score from 48 for a Dwarf Chinkapin Oak in Bridport to 439 for a Cottonwood in Hubbardton. Freeman continued to maintain the list up until 2008, when he turned his files over to FPR. Freeman is still very much involved with the list and maintains correspondence with big tree hunters.
How to Measure a Big Tree
The Vermont Register of Big Trees uses AF's formula to determine whether a tree is a champion.
There are three measurements that we look for:
Circumference in inches, a measure typically taken 4.5 feet above the ground. Root swell or very low branches may require adjustment from the lower measuring point.
Height in feet, measured from the ground to the highest branch. There are many ways to measure the height of a tree. One of the easiest methods is to use a metal tape measure laid out on the ground near the tree or up against the tree to show either 10 (or 20) feet as a reference. Then, by using a thumb and index finger at arms-length and angled parallel to the tape measure on the ground, thumb and index finger, representing the known measure can be sized up against the tree to estimate the tree’s height. The number of lengths are then simply added up and multiplied by 10 (or 20) feet for the final score.
Crown Spread is measured by extending the outer crown edge down to the ground and measuring widest and shortest diameter. Average these.
Once you have these measurements, calculate the tree's total points by using the formula below.
Big Tree Formula
Trunk circumference in inches
+ Height in feet
+ 1/4 of the crown spread in feet
= Total Points
National Register of Big Trees
The National Register of Big Trees is maintained by American Forests, a non-profit citizens' conservation organization founded in 1875. Since 1940, citizens have helped the organization identify the largest known species across the United States.
Search the List of Vermont Big Trees: