The Red List and Ex situ Survey of Oaks

The Red List of Oaks

The Red List of Oaks (2007) assessed 208 of the 500 oak (Quercus) species found worldwide. This report identified 78 wild oaks in danger of extinction and raised concern over the lack of data for over 300 species. Oaks are under threat in the wild from general forest loss and over-exploitation of particular species.

The Red List of US Oaks

The Red List of US Oaks (2017) details for the first time the distributions, population trends, and threats facing all 91 native oak species in the U.S., including updated versions of previously published assessments. Sixteen species were assessed as threatened and are clear priorities for conservation action. California contains the highest number of oak species of conservation concern (nine species). Some of the major threats to oak species in the US include both native and non-native pests and diseases, climate change, urban development, and agricultural expansion.

Global Survey of Ex situ Quercus Collections

The Global Survey of Ex Situ Quercus Collections (2009) is a vital step in ensuring the conservation of oak species by identifying which of the threatened species are held in ex situ collections around the world. The survey identified 3,796 oak records from 198 institutions in 39 countries. However, only 91 ex situ records representing just 13 of the most threatened oaks were located. This means that more than half of the Critically Endangered or Endangered taxa are currently not known to cultivation and therefore at great risk of extinction if threats that they are facing in the wild are not addressed.

Quercus hirtifolia (Endangered) seedlings in Mexico

Associated resources

  • The Red List of Oaks

    Conservation Prioritisation, Tree Conservation / Publication / English
  • The Red List of US Oaks

    Conservation Prioritisation, Tree Conservation / Publication / English
  • Global Survey of Ex situ Quercus Collections

    Conservation Prioritisation, Tree Conservation / Publication / English

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