Understanding the current state of trees within the U.S. is imperative to protecting those species, their habitats, and the countless communities they support. Until 2022, most species native to the contiguous U.S. were not assessed or were outdated in the two most widely used threat assessment platforms in the U.S.: International Union for Conservation of Nature (IUCN) Red List and NatureServe.
With the goal of cooperative action in mind, The Morton Arboretum coordinated an updated, standardized checklist and threat analysis of all native trees in the contiguous United States. These efforts were undertaken in partnership with Botanic Gardens Conservation International-US, NatureServe, United States Botanic Garden, and the USDA Forest Service.
The final report presents a summary of the analysis, including patterns in threats and conservation efforts for the most at-risk species. The authors report that approximately 11 to 16 percent of the 881 tree species in the U.S. are threatened with extinction, with the greatest threats being invasive pests and diseases.
The report, published in a special issue of Plants, People, Planet focused on the Global Trees Assessment, details the repeatable assessment process to further collaboration in global tree conservation.
Researchers encourage the conservation community to use these results to prioritize and advocate for strategic species and ecosystem conservation to ensure the future of trees.