Eligible Species

There are nearly 900 species and varieties eligible for the American Forests Champion Trees national register.

These species must be recognized as either native, non-native, naturalized or a recognized naturally occurring variety in the United States. Hybrids, cultivars, ornamentals and unclassified varieties are excluded. American Forests has based this list on sources such as the USDA Plants Database and the Integrated Taxonomic Information System (ITIS).
Note: The classification of various species as invasive is not consistent across state boundaries, since each species does not always exhibit invasive characteristics in every location. State coordinators shall decide whether a nominated tree fits the definition of invasive in their state and therefore exclude that species from nomination to the National Register.

To begin the nomination process, search the current register for current champions or our list of eligible species without champions. Once you’ve determined your specimen meets the criteria to be a contender, ensure you accurately measure the tree.

Tree Measuring 101

To nominate a tree to become a champion, you need three measurements:

  • Trunk Circumference
  • Height
  • Crown Spread

Trees of the same species are compared using the following calculation:

Trunk Circumference (inches) + Height (feet) + ¼ Average Crown Spread (feet) = Total Points

Measuring Guidelines Handbook

American Forests released the National Big Tree Program’s tree-measuring guidelines handbook in 2014. This comprehensive guide was assembled and published to ensure accuracy and integrity in the national register of champion trees.

American Forests Champion Trees Measuring Guidelines Handbook

Champion Tree Nominations

If you have determined your tree is a candidate for champion status, nominate it!

Nominations for the 2018 edition are now open through Arbor Day, which is April 27, 2018.

Crowning a Champion

The tree with the most total points is crowned national champion. When multiple candidates exist, the new “3 x 3” rule is employed, meaning co-champions are crowned using the following criteria:

  • If the trees are under 100 points and within 3 points.
  • If the trees have more than 100 points and the differential is 3 percent of the total.

The American Forests Champion Trees national register is released annually. Check out the 2017 national champions and co-champions.

Big Tree State Coordinators

While American Forests is available to help with any questions you may have during the nomination process, it may be best to first contact the big tree coordinators in your state. The state coordinators of the National Big Tree Program are a great resource for initial program information or measurement and nomination clarification.