By Barbara Walvoord
Most living things in our woods have either green leaves or mouths. The ones with green leaves—the trees, shrubs, and wildflowers—practice photosynthesis–using sunlight to make food out of water and carbon dioxide.
The ones with mouths are creatures like insects and rabbits who eat the plants that have made food out of water and carbon dioxide, and then creatures like the bobcat, coyote, and hawk, who eat the creatures that have eaten the food that the plants have made. This is the house that Jack built, otherwise called a food web.
But this beautiful red Russela mushroom I found in our woods has no green part and no mouth. So how does it get its food?
The answer lies underground. The red mushroom above the ground is only the sex organ. It releases the spores that will travel off to form new mushrooms.
The Russela’s “mouth” for food is its extensive underground network of fibers that wrap around plants’ roots and absorb some of the sugar that the plant has produced via photosynthesis. Russela prefer tree roots, but almost all plants have these mycorrhizal fungi.
This mushroom doesn’t just take; it gives back. It does more for our trees than any bag of Scott’s Weed ‘n’ Feed. The underground fibers:
- Fertilize the plant by making minerals, especially phosphorus, more usable by the plant
- Build soil structure and porosity by creating a sticky protein called glomalin, which decreases erosion and topsoil loss
- Suppress pathogens that would attack the tree
- Improve root systems of trees by connecting them to one another and extending their reach into the surrounding area.
- Increase the efficiency of water uptake by the roots
The oldest plant fossils show evidence of this symbiotic relationship with fungi. In fact, the theory goes, it was the help of fungi that enabled plants to move from sea to land in the first place, nearly 500 million years ago.
So the house our forest builds is more complex even than Jack’s house: ours has to include the mushroom that ate the plant sugars that the mushroom helped the plant to produce in the first place.