Frequently Asked Questions

Q. How do you determine a national champion?

A. To calculate a tree’s total point value, American Forests uses the following equation: Trunk Circumference (inches) + Height (feet) + ¼ Average Crown Spread (feet) = Total Points.

A nominee will replace a registered champion if it has more points. When two trees have scores that fall within five points of each other, they are listed as co-champions. Champions listed in the registry must be re-measured every 10 years to maintain their champion status.

Q. How often is the National Register of Big Trees updated?

A. The National Register is updated twice a year in the spring and fall on American Forests’ website. The register is published as a printable PDF every two years. To view the current register, click here.

Q. How do I nominate a tree?

A. Click here to learn more about how to nominate a tree and what is required for each nomination.

Q. What species are eligible for the National Register of Big Trees?

A. There are more than 870 species and varieties eligible for the National Register of Big Trees. A species must be recognized as native or naturalized in the United States. Hybrids and minor varieties are excluded. American Forests has based this list on sources such as the USDA Plants Database and the Integrated Taxonomic Information System (ITIS). To view the list of eligible species, click here.

Q. How can I add a species to the National Register of Big Trees?

A. Additions to the species list for the National Register of Big Trees should be submitted to American Forests by January 1st for the spring register and July 1st for the fall register. A proposal letter with supporting reference materials is required and will be reviewed by scientific experts and the Big Tree Committee. A letter from an expert in botany or plant taxonomy is recommended.

Q. What is a native or naturalized tree?

A. Native trees (also called indigenous) are those species that grew naturally or spontaneously in the undisturbed forest vegetation before the arrival of Christopher Columbus or other European explorers. A naturalized tree is an introduced species that has become common and established itself as though wild, reproducing and spreading naturally. To view the list of eligible species, click here.

Q. What is the difference between a tree and a shrub?

A. Trees are woody plants that have one erect perennial stem or trunk at least 9 ½ inches in circumference at 4 ½ feet above the ground. They also have a definitively formed crown of foliage and a height of at least 13 feet. In contrast, shrubs are small woody plants, usually with several perennial stems branching at the base.

Q. How do I identify a tree?

A. Every state has a Big Tree Program that lists state champions. The state coordinator for your respective state will be able to assist you in identifying and measuring your tree. To find a listing of state coordinators, click here.

Q. Does my state have a Big Tree register?

A. All fifty states, and the District of Columbia, have their own registers. To find your state program in our directory, click here.

Q. Can I visit a national champion? If so, how do I find its location?

A. Many of our champions are located on public land (such as national forests or national and state parks), where you can visit them. However, if a tree is located on private land, we ask that you respect the landowner and ask permission before making a visit. You can learn more about the specific location of trees by contacting your state coordinator.