top of page



Introduction / Background / Justification

Trees are of vital importance ecologically, culturally and economically. The interlinked biodiversity crisis and challenge of global climate change cannot be addressed without informed management of tree species.


The Global Tree Assessment aims to compile extinction risk information on the c. 60,000 tree species worldwide. The outcomes of these analyses provide prioritization information to ensure that conservation efforts for trees are effective.


The Global Tree Assessment has been made possible over the past five years by a global network of over 60 institutional partners and over 500 experts. Through collaboration with experts, Red List Authorities and specialist groups all over the world, including CNCFlora in Brazil, Asociación Colombiana de Herbarios in Colombia and Provita in Venezuela, we have produced conservation assessments, assessing the risk of the species becoming extinct. The final data set consists of IUCN Red List assessments and existing National and Regional assessments.


In September 2021 the State of the World’s Trees report was published. We now know 30% of tree species are threatened with extinction, and at least 142 tree species are recorded as extinct or extinct in the wild. The information collected is visualised on the GlobalTree Portal, showing statistics on a global, national and species level. The main threats to tree species are forest clearance and other forms of habitat loss, direct exploitation for timber and other products and the spread of invasive pests and diseases. Climate change is also having an impact.

It was found that over two-thirds of tree species are recorded in at least one protected area. About a third of tree species exist in botanic gardens or seed banks. However, the majority of the species protected are not threatened with extinction.


The collation of information on the world’s almost 60,000 tree species recognises their global importance. It gives us an information base to call for a new focus on planning and carrying out biodiversity conservation and ecosystem restoration. The report identifies the regions where further action is needed. It provides recommendations for urgent action and calls for a new coalition to facilitate the action and expertise required.


tree species; conservation assessments; extinction risk; prioritisation; Red List; biodiversity

Katharine Davies

Presentation within symposium:

S-11 Conserving the world’s macroflora – from tree Red List assessments to tree conservation in action

The Global Tree Assessment: State of the World’s Trees


bottom of page