Trees Mycorrhizal Fungi
…connections are made by the filaments of fungi that grow in and around plant roots and produce many of the forest mushrooms we know and love. They bond trees so intimately that the more you learn about them, the more it is a struggle to view any tree as an individual. Forest trees and their root fungi are more or less a commune in which they share resources in a fashion [quite] unabashedly socialist…
…Mycorrhizal fungi like Rhizopogon partner with plant roots because each gets something out of it. The fungus infiltrates the plantsí roots. But it does not attack ó far from it. The plant makes and delivers food to the fungus; the fungus, in turn, dramatically increases the plantís water and mineral absorptive powers via its vast network of filaments. They provide far more surface area for absorption than the meager supply of short root hairs the tree could grow alone. What has not been appreciated until relatively recently is both how complex mycorrhizal fungal networks can be and that they can also act as conduits between trees
…To my surprise, I discovered when researching this post that it has been known for a while that trees of different species can communicate with and support one another via their mycorrhizae. I had already known that plants can communicate with unrelated species through the air; plants getting chomped by herbivores release volatile chemicals that are sensed by neighboring plants, who up their defenses pro-actively. But communicating ó and even sharing resources ó through mutual root fungi was news to me.
…Finally, itís also possible the fungus played the more calculated role of a broker with its own interests in mind and ďacted to protect its net carbon source,Ē in the words of the authors, ďby allocating carbon and signals to the healthy, more reliable ponderosa pine.Ē
In this way, mycorrhizal fungi may help forests be more resilient to assault in general but especially to those from climate change by transfering existing, hard-won food resources from a dying species to a species migrating northward into newly available habitat, but struggling to get a toehold.
…All trees all over the world, including paper birch and Douglas fir, form a symbiotic association with below-ground fungi. These are fungi that are beneficial to the plants and through this association, the fungus, which canít photosynthesize of course, explores the soil. Basically, it sends mycelium, or threads, all through the soil, picks up nutrients and water, especially phosphorous and nitrogen, brings it back to the plant, and exchanges those nutrients and water for photosynthate [a sugar or other substance made by photosynthesis] from the plant. The plant is fixing carbon and then trading it for the nutrients that it needs for its metabolism. It works out for both of them.