Global Tree Conservation

Conservation Gap Analysis of U.S. Trees in Nine Priority Genera

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Trees are facing increasing threats globally, including habitat loss, natural systems modification, land-use change, climate change, and pests and diseases. With more than 800 native tree species in the continental United States and more than 60,000 tree species globally, prioritizing species and conservation activities is vital for effectively utilizing limited resources. To facilitate this conservation planning, The Morton Arboretum developed a gap analysis methodology that examines both the accomplishments and most urgent needs for in situ (in the native habitat) and ex situ (in managed botanical collections) conservation of priority, at-risk tree groups in the U.S. This methodology was first implemented in its flagship report, Conservation Gap Analysis of Native U.S. Oaks

Seven additional reports have been completed and present the results of a second phase of gap analyses, which focused on native U.S. trees within a group of priority genera. These were selected due to particular economic importance, potential challenges with conventional seed banking methods, and/or threats from emerging pests and diseases: Carya (Hickories), Fagus (American Beech), Gymnocladus (Kentucky Coffeetree), Juglans (Walnuts), Pinus (Pines), Taxus (Yews), and selected Lauraceae (Laurels; including Lindera, Persea, and Sassafras).

Each report provides a summary of ecology, distribution, and threats, followed by new results from two recent surveys: a global survey of ex situ collections and a conservation action questionnaire distributed to a wide range of conservation practitioners. More than 350 collaborators provided data for these analyses.

The reports also each present a one-page “Conclusions and Recommendations” section, which can be referenced for a summary of the species distributions, threats, coverage in ex situ collections, known conservation actions, and broad recommendations moving forward.

The data provided in these reports will aid in prioritizing conservation actions and coordinating activities among stakeholders, furthering efficient and effective conservation of keystone U.S. trees.

For more information about the Arboretum’s tree conservation work, see Conservation Recommendations for Trees Under Threat.

Funding Sources

USDA Forest Service

Institute of Museum and Library Services


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