The 'zombie' tree is fed by the forest

The New Zealand kauri tree roots transplant roots to draw water and nutrients from neighboring trees, surprising researchers.

The researchers found a kauri tree , a coniferous tree that can reach up to 50 meters tall, in the forests of New Zealand. The leafless tree trunk seemed to have died long ago but still survived by absorbing water and nutrients from its neighbors, according to a study published July 25 on the creation of iScience.

Picture 1 of The 'zombie' tree is fed by the forest
Stump kauri tree in the forest in New Zealand.(Photo: Live Science).

Beneath the soil, the stump is part of a forest "super-entity" with a network of roots tangled together to share resources in populations of tens, even hundreds of trees. By rooting with neighbors, kauri roots absorb water and nutrients at night while other trees gather resources during the day.

"The benefits to the stump are clear. It will die without the rootstock, because it doesn't have any green tissue , " said Sebastian Leuzinger, co-author of the study, associate professor at the University of Technology. Auckland, New Zealand, said. "But why do trees maintain life for ancient trees on the forest floor while parasites don't seem to benefit them?"

Leuzinger and colleagues tried to find the answer by studying nutrients flowing through the root of the parasite and the two nearest neighbors. Using several sensors to measure the movement of water and plastic (containing important nutrients) across three plants, the team found interesting: the dead tree and its neighbors drinking water at opposite times. together.

In the daytime, when the neighbor plants concentrate on transporting water from the roots to the leaves, the dead stump does not work. In the evening, when the neighbor tree rested, the penguin tree circulated water through the rest of the body. They alternately suck water in a hydraulic network.

Although the penguin tree has no leaves, its roots may still be useful for other photosynthetic trees in the forest. Another theory is that it has rooted roots with neighbors for a long time before becoming a dead tree. Because nutrients still flow through the roots of the dead tree root and the entire network, neighbors may not recognize the deficiency.

Collaboration between the trees urges Leuzinger and his colleagues to rethink the concept of forests."Maybe we are not studying each individual tree but the whole forest as a super entity , " Leuzinger said.

The supernatural forest can increase protection in drought conditions, helping water-shortage plants have the opportunity to share resources with neighbors more fully. However, grafted roots also have disadvantages. Along with the nutrient shared alternately between plants, harmful pathogens are also easily transmitted from an infected tree to the entire forest through the underground root network. In particular, kauri trees are threatened by kauri dieback disease spread through pathogens in the soil.