GTA – Global Tree Assessment

GTA – Completing the Global Tree Assessment worldwide

Partner: BGCI – Botanic Gardens Conservation International
Years: 2015-2027

Since 2015, Botanic Gardens Conservation International (BGCI), with the support of Fondation Franklinia, has been coordinating the Global Tree Assessment, which assesses the extinction risk of all the world’s tree species through the IUCN Red List. Documenting the conservation status of a group of nearly 60’000 species is the largest initiative in the history of the IUCN Red List of Threatened Species. It represents a Herculean effort by hundreds of individuals, coordinated by BGCI and the IUCN Species Survival Commission.

The Global Tree Assessment (GTA) aims to ensure that conservation assessments for all tree species are available to policy makers and conservation practitioners. Intensive research has been carried out in recent years to compile information on the extinction risk of the world’s 58’497 tree species. We now know that 30% of tree species are threatened with extinction. Preliminary results are available in the flagship State of the World’s Trees publication. The GTA was made possible by a global network of more than 100 institutional partners and over 1000 experts.
The first phases of the GTA have assessed the conservation status of over 80% of known tree species. Trees now represent 25% of all assessments available on the IUCN Red List. For the current phase (2024-2027), BGCI will produce 2’000 tree assessments annually, covering i) newly described species (and other taxonomic updates), ii) out-of-date assessments, and iii) species where new data have become available that warrant a re-assessment.
The project will also ensure that the extinction risk assessments of trees on the IUCN Red List are expanded and kept up to date, and that the information generated by the GTA is communicated, mobilised and integrated into conservation planning and action. Thanks to this work, conservation actions should be implemented where they are most needed, resulting in zero tree extinctions.