Scientists Save Seeds From World's Last Rare Island Tree

The world's loneliest tree just got a lifeline, thanks to a daring rescue mission on a remote Chilean island.

Dendroseris neriifolia once grew across Robinson Crusoe Island, part of the Juan Fernández Islands chain 420 miles off mainland Chile. Today, just one individual remains in the wild, clinging to a volcanic cliff supported by ropes to keep it from tumbling down.

Every March, when the tree's seeds ripen, Chilean park rangers make a grueling journey to reach it. The trip requires a four-hour boat ride followed by a two-hour climb up rocky terrain with no road access.

This year, their mission carried extra weight. For the first time ever, seeds from this critically endangered species were collected for long-term storage at England's Millennium Seed Bank at Kew Wakehurst.

Park rangers climbed along the trunk to reach flowering branches, catching mature seeds in nets. Of the 29 seeds that made it to England, X-ray analysis revealed 25 were potentially viable.

Seven seedlings are now putting down roots at the botanical garden. "Through this project, we hope to be able to produce more seed from the plants which we have growing now once they reach flowering age," said Alice Hudson, partnerships officer at the Millennium Seed Bank.

The tree's decline spans more than a century. Italian botanist Carlo Bertero first described the species in the 1830s when it was still relatively common. By 1980, only seven trees remained, each reaching up to 16 feet tall.

Habitat loss, invasive species, grazing animals, fires and forest clearing pushed the species to its current desperate state. All 11 species in the Dendroseris genus are in decline, and until now, no seeds from any of them had ever been stored in a seed bank.

The Bright Side

Seed banks spread the risk. If anything happens to the wild tree, scientists now know how to germinate its seeds and can grow new plants.

The controlled environment also lets researchers study the species up close. Many plants have complex germination requirements that need testing and refinement before restoration efforts can succeed.

Chilean conservationists will use the knowledge gained from growing these seedlings to develop future restoration protocols. Once the young plants at Kew Wakehurst mature and flower, they'll produce even more seeds for storage and potential reintroduction to the wild.

The rescue shows how international collaboration can pull species back from extinction's edge, one precious seed at a time.