Zombie Tree Reanimates Leaves Into Roots: ‘Truly Novel’

Scientists have discovered a zombie tree that converts its leaves into roots as it dies.

The Cyathea rojasiana tree fern, which is native to Panama in Central America, was studied by plant biologists across multiple institutions. Their findings are published in the journal Ecology.

They found that the tree restores its dead leaves and converts them into roots. These roots then feed nutrients back into the tree, making it come alive once again, the study reported.

This is the first time this phenomenon has ever been reported in a tree.

“This is a truly novel repurposing of tissue. And it’s distinct from what we know other ferns do,” University of Illinois Urbana-Champaign plant biology professor James Dalling said in a summary detailing the findings.

Dalling, who is also a research associate at the Smithsonian Tropical Research Institute in Panama, made the discovery while studying a completely different plant in a forest reserve.

He found that the dead leaves of the Cyathea rojasiana had implanted themselves deep into the soil. He then realized that the dead leaves had roots growing from them.

After some lab work to find out more, researchers found these roots were actively drawing nitrogen out of the ground, and feeding it back into the original plant, the study reported.

Usually, fallen leaves and shoots from trees will create a completely new plant. But the Cyathea rojasiana works to sustain itself. Dalling suggested this has never been reported before because the dead leaves look like decaying plant matter. Therefore, it is easy to overlook them and realize that they are not dead at all, but are coming back to life.

The Cyathea rojasiana is an ancient tree and can be traced back to the Jurassic period, the study reported. The researchers believe that it adapted to this phenomenon due to the poor nutrients of the volcanic soil at the time.

“Panama is a land bridge between North and South America that coalesced 7 million years ago out of an archipelago of islands, and those islands are the result of volcanic activity in the past,” Dalling said in a summary. “In one site we discovered, a layer of volcanic ash several meters deep that looks like sand that you would dig up on a sandy beach. The plants that grow there are distinct from those that we find elsewhere in that forest reserve.”

Scientists know that this tree also grows incredibly slowly over time. A summary of the study’s findings described this as a “major investment of resources” when the plant repurposes itself.

“The tree ferns seem to be putting out tentacles to sample the surrounding soils,” Dalling said. “They’re able to sample a greater range of nutrient environments for the same amount of investment of rootlets than if they just sent out a single rooting structure all around the fern. I think it’s all about the economics of how they use resources in a patchy environment. They’re probably putting on one or two leaves a year, and so they’re adding on the order of a few centimeters of height a year,” Dalling said.

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