Forest ecologist Suzanne Simard’s research states that trees talk to each other. Others are not so sure
A renowned British Columbia forest ecologist is defending her research on how trees communicate after a review of citations claims there is insufficient evidence to support her work.
Suzanne Simard, Professor of Forest Ecology at the University of British Columbia, gained international recognition for her research on forest communication networks. Their results suggest that trees in a forest are connected and communicate with each other via underground fungal networks – colloquially known as the “wood wide web”.
She is a leading figure in this research group and directs a long-term experiment called The Mother Tree Project.
Simard’s work, which includes a New York Times bestseller, describes how trees are connected by fungi at their roots called mycorrhizae. Through mycorrhizal networks, Simard says, trees are able to exchange resources, share nutrients with younger seedlings, and release chemicals to alert one another of distress.
But authors of a citation review published in Nature Ecology and Evolution say this research may not be applicable to every forest.
Review co-author Justine Karst, who studies forest mycorrhizal ecology at the University of Alberta, notes that she challenges the claim that mycorrhizal networks are widespread in forests. The article states that only two forest types were studied – Douglas fir forests in BC and pine forests in Japan.
“It would be really valuable to map more common mycorrhizal networks in different forest systems around the world,” Karst said.
The analysis by Karst and her co-authors also challenges the study’s claims that fungal compounds benefit seedlings and trees can recognize their kin through mycorrhizal networks.
Simard told CBC the article misses an important point of research, claiming that studying the interactions between trees is vital to protecting forests.
“The article really focuses on a very narrow part [of the research],” said Simard. “That doesn’t change the idea that forests are communicatively connected. And that we have to nurture, nurture and nurture these relationships – that doesn’t change either.”
Karst said they don’t dispute the importance of mycorrhizal fungi in forests, but do question their influence of fungal compounds on how trees function, and said there’s also a possibility nutrients could be found through other means, such as the soil. can be transferred.
“It’s possible that the carbon is just moving through the soil,” Karst said. “The roots give off some liquid, there may be carbon in that liquid. It then moves through the soil and is picked up by another tree.”
Simard says she has done work that has shown how trees transfer resources through multiple pathways underground.
“I think what [the reviewers] We criticize that we have claimed that this mycorrhizal network is the only one operating, and that is not true,” Simard said.
“All of the papers recognize that all of these pathways exist together, and it makes sense that trees have multiple ways to interact with, share, and even compete for resources.”
Calls for more research
Melanie Jones, a biology professor at UBC Okanagan and a co-author of the review, calls for other types of forests to map their fungal associations.
“Like the Amazon, nobody has mapped these fungal compounds there,” Jones said. “Our concern is really that we shouldn’t automatically assume this is happening everywhere.”
Simard says she welcomes calls for more research.
“[More research is] always needed, especially in such complex ecosystems as forests. We need to work together as teams to really solve these complex problems,” Simard said.
She says criticism is expected in research communities.
“It’s normal for science to keep checking and going back and forth,” she said. “It’s a normal part of the scientific method.”