This meeting and presentation took place both in person at the Liederkranz Club and concurrently online via Zoom.
At 7:00 pm, Board Member Richard Davis called the Society meeting to order.
Richard made the following announcements:
- He welcomed all to this second hybrid in-person plus on-line meeting of the Linnaean Society.
- He reminded members to pay their membership dues if they haven’t already done so.
- Fall field trips are in full swing. Register for them on the Society’s website.
- The next regular members meeting will start at 7:00 pm, November 11th, returning to the usual second Tuesday of the month. The cash bar will open at 6:30 pm. It will again be a hybrid event held in person at the Liederkranz Club at 6 East 87th Street and concurrently online via Zoom.
- The Society is still searching to fill the open position of president. Richard asked the audience members to email the Linnaean secretary if they are interested in serving, or if they know of someone who might be. In the meantime, until a president is elected, the role will be filled month by month on a rotating basis by a board member or a past president.
- He welcomed the new (September, 2025), members to the Linnaean Society:
- Robin Daly
- Beverly DeVoe
- Trustum DeVoe
- Eliot Jenkins
- Bruce Leibstone
- Patrick Marcoux
- Jane Marke
- Catherine Pan-Giordano
- Kimberly Schwab
- Wendy Spence Schmidt
- Terry Von Ploennies
At 7:02 pm, Richard turned to the lecture program and welcomed the night’s speaker, Dr. Rick Lankau, professor in the Department of Plant Pathology in the College of Agricultural & Life Sciences at the University of Wisconsin – Madison.
Lecture: “Forest Fungi and Forest Health: What Do We Know, What Don’t We Know, and How Can We Use This Knowledge to Preserve and Restore Healthy Forest in a Changing World,” presented by Dr. Rick Lankau
From the perspective of mycology, referring in particular to the fungi that interact with plant and tree roots, tonight’s topic connected mechanisms of what happens beneath the forest floor with the dynamics and implications of climate change.
Dr. Lankau began with an overview of fungi: what they are; where they fit in the phylogenetic tree; and the relatively recent understanding that they are more closely related to animals than plants. He then described the three major roles that fungi play in the world’s forests—as decomposers, as pathogens, and as mutualists—and how each of these roles contributes to the health of the forest. Decomposers help to make nutrients such as nitrogen, phosphorous, and potassium accessible to plants through digestion (breaking down) of dead wood. Pathogens are thought to contribute to tree diversity in forests thanks to fungal species being specialists that target a single or a limited number of tree species. The specialist fungi create dead zones where seedlings of the targeted adult tree cannot grow, thereby opening up those areas to other tree species that are not affected by the same pathogen. Mutualists both extract food from the host plant and, in return, provide benefits to the plants such as soil nutrients, the ability to tolerate drought and temperature extremes, and defense against pathogens.
Dr. Lankau noted that the symbiotic relationship between fungi and plants is a very active area of research, including mycorrhizal fungi—an important focus of his talk. He explained that mycorrhizal fungi are characterized by connecting plant root tissue and the soil—they live both inside plant roots and out in the soil. He talked about the two major groups: 1) the arbuscular mycorrhizae (AM), an ancient fungi group (around 400 million years old) that is in almost all plants and dominates in warm regions of the world; and 2) ectomycorrhizae (EM), a more recent fungi group (50 million years old) that is less common, but serves a very important role in forests, especially in the colder climates of the world. The two overlap in the world’s temperate forests. Apart from their root-and-soil connection commonality, these two groups have functional differences, and Dr. Lankau talked about these, including their different rates of decomposing litter; the global habitats they favor; the species they colonize; and, how these differences may impact climate change and forest adaptations to climate change.
The “Wood Wide Web” is a colloquial reference to the idea of common mycorrhizal networks (CMN). Dr. Lankau explained the theory: “CMN occur when the same fungal individual forms mycorrhizal connections with multiple host trees, forming a physical connection between trees.” He offered his views on this concept: Laboratory studies have shown that fungi can connect to multiple trees and that nutrients and water can move between trees by CMN. Do these connections happen in nature? He thinks probably yes, though studies aren’t conclusive. More controversial is the idea of adult trees “feeding” seedlings. He feels it is possible—some lab studies seem to suggest this is so—but his view is that if it is happening, it is at a very low level. On the final concept—of mother trees recognizing and feeding their offspring—he thinks that is unlikely because currently there is no plausible explanation for how trees would recognize each other and, so far, there is not much evidence that this is happening. But should it eventually be determined to be happening, this might be an important mechanism for seedling survival in stressful conditions such as drought.
Forests play a big worldwide role in the production and sequestration of carbon dioxide, a consequential greenhouse gas in the earth’s atmosphere that is driving global warming and climate change. Additionally, forests are under threat because of these changes. Fungal microbial processes are an active area of study to address the question: Can microbes help trees cope with climate change, improve tree health, and restore forests?
Dr. Lankau described some of the research his lab is doing to address these questions. Because trees evolve slowly and don’t move easily or rapidly, an alternative option for survival might be to change the species of fungi that the trees associate with. His lab explored this idea by inoculating tree seedlings with microbes from different habitats than their own—microbes from places that were drier or wetter, hotter or colder—and then stressing the seedlings with different environmental conditions than those of their normal habitat. Results showed that the seedlings were resilient to temperature and moisture stressors when these alternative microbes were introduced. New directions of research are focused on the fundamental science of how these systems work, in order to understand why inoculation with different microbes improves resiliency.
Nurseries are a critical piece in the puzzle of reforestation projects. Approaches to fungi management are important to the success of these efforts. Dr. Lankau described his lab’s research in this area, and the way his lab works with nurseries to introduce best practices for fungi selection, inoculation, and, ultimately, tree reforestation survival.
Dr. Lankau’s final topic was his citizen science project, “Forest Fungi Project,” which involves mapping the fungi species in the eastern North American temperate zone. (Details can be found online at forestfungi.russell.wisc.edu.) He encouraged the audience to participate—to collect samples of tree roots and mail them to his lab for DNA analysis and tracking. The goals of the project are to identify which fungi associate with which trees, and in which climate conditions. This information is then used in experiments to identify which fungi lead to better outcomes for tree species survival. Ultimately, the combined results inform guidance and collaboration with nurseries and forest restoration efforts for tree survival success.
Following is Dr. Lankau’s abstract of his talk:
From the time the first plants established themselves on land, plants have relied on fungal partners for their survival. Today all plants interact with fungi in some way, ranging from beneficial symbionts vital for plant growth to deadly pathogens that can wipe out whole fields. Forests, in particular, rely on diverse fungal communities to cycle nutrients, promote tree growth and stress tolerance, and maintain diverse tree mixtures. In this presentation, Dr. Rick Lankau will discuss what is currently known about the roles fungi play in healthy forests and highlight where the biggest scientific gaps and controversies still exist. Then, Dr. Lankau will describe some of his current research investigating how fungal communities are distributed across the forests of the eastern US, how fungi may be promoting resilience of trees in the face of changing climates, and finally, how we can use our knowledge of fungal interactions to enhance restoration of forests.
At 8:01 pm, Vice President for Programming Karen Becker thanked Dr. Lankau for a really fascinating talk. She then hosted the Q&A session with questions from both the in-person audience and from those on Zoom.
At the conclusion of the Q&A, Karen Becker thanked Dr. Lankau again for an absolutely fascinating topic and talk. At 8:31 pm the meeting was adjourned.
Dr. Lankau’s presentation and the Q&A session have been recorded in their entirety, along with Board Member Richard Davis’ opening meeting remarks. The recording is available for viewing on the Linnaean Society of New York website under the dropdown menu: Programs/Watch/ and on the Society’s YouTube channel, https://www.youtube.com/@linnaeanny/videos
Respectfully submitted by Lisa Kroop, Recording Secretary