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Mexico: the mystery of the centuries-old oaks of Baja California Sur (and the secret to save them from extinction)

BBC News

By Alexandra Martins

They are descended from ancestors that lived more than 50 million years ago and have faced all kinds of challenges.

But today they are still standing, but only in one place on the planet.

In the Sierra La Laguna, in the state of Baja California Sur, in northwestern Mexico, lives the only population of a species of oak known as encino arroyero .

" They are survivors, these trees are heroes ," Silvia Álvarez Clare, a Costa Rican ecologist and director of the Global Tree Program of the Morton Arboretum, a botanical garden and conservation center in Illinois, United States, told BBC Mundo.

Mexico is the country with the greatest wealth of oak species in the world and many of them are threatened. In the case of the stream oak, whose scientific name is Quercus brandegeei , the biggest problem is that the species is not regenerating. Centennial trees can be found, but there are no seedlings or "baby oaks" born from acorns, as oak seeds are called. They are like " a community of pensioners of stream oak , because we have not been able to find juveniles," Álvarez Clare describes them. "And in a healthy population of trees there are a lot of young individuals."

A project promoted by the Morton Arboretum, together with Mexican scientists and local communities, seeks not only to solve the mystery of the ancient oaks but also to save this iconic and precious species from extinction.

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Date: 
Thursday, February 10, 2022
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