Big tree designations are made on most species throughout the United States. The Utah Division of Forestry, Fire and State Lands maintains the Utah Register of Big Trees, a listing of the biggest trees in the state.
The National Register of Big Trees is maintained by American Forests, a non-profit organization dedicated to healthy forests in communities throughout the United States. The American Forests National Register has been maintained since 1940. The largest tree of each species in the country is designated as a National Champion. And Utah is home to many National Champions.
The Utah Division of Forestry, Fire and State Lands encourages all tree lovers, hikers, campers, and outdoor enthusiasts to be on the lookout for champion-sized trees. Trees certified as fulfilling "Big Tree" criteria will be listed in the Utah Register of Big Trees with the person(s) nominating the tree listed as champion tree finders. Depending on the tree's status, it could also qualify as a national champion and the person(s) nominating the tree will receive recognition in the National Register of Big Trees.
So what is a Big Tree?
The first step in identifying a Big Tree is to take measurements, but keep in mind that some Big Tree champions are quite small because some species are not very large – even at maturity. American Forests has established guidelines for measuring trees, and the Utah Division of Forestry, Fire and State Lands follows the same guidelines.
Measuring Guide (courtesy of American Forests)
Before nominating a tree, you need to know 3 measurements: (1) Trunk Circumference (measured in inches), (2) Vertical Tree Height (measured to the nearest foot), and (3) Average Crown Spread (measured to the nearest foot).
American Forests uses the following calculation to determine a tree's total points: Trunk Circumference + Height + ¼ Average Crown Spread = Total Points
A nominee will replace a registered champion if it has more points. When two trees have scores that fall within 5 points of each other, they are listed as co-champions.
- Circumference is measured at 4 ½ feet above ground level in inches.
- If the tree forks below 4 ½ feet, measure the circumference of the thickest branch above the 4 ½ feet.
- If a tree is on a slope or uneven ground, measure the trunk on the high and low sides of the slope and take the average.
- The vertical height of a tree is measured in feet, which includes the whole tree, dead or alive. It can be measured using an Abney hand level, a hypsometer, or a transit.
- Alternatively, you can use the stick method: Hold the stick at its base vertically, making certain that the length of the stick above your hand equals the distance from your hand to your eye. Staying on ground level (or on the same contour as the base of the tree), move away from the tree while sighting the trunk base above your hand. Stop when the top of the stick is level with the top of the tree. You should be looking over your hand at the base of the tree and, moving only your eyes, looking over the top of your stick at the top of your tree. Measure how far you are from the tree and that measurement - in feet - is the tree's height.
Average Crown Spread
- Average Crown spread is measured in feet. Add the widest and narrowest crown spread and divide the total by 2.
- You can also use the pencil method outlined below to measure the average crown spread:
1 - Outline the tree's crown by sticking pencils into the ground along the outer tips of the tree's branches.
2 - Measure the distance between the two pencils that are the farthest apart (C&D). Write down that number.
3 - Measure the distance between the two pencils that are the closest together (A&B) but still on opposite sides of the tree. Write that number down.
4 - Add the two numbers and divide by two. This new number is the tree's average crown spread.
Nominate a Big Tree