Mushroom restoration finds niche
Fungus being used to restore damaged lands

Michael Freeman takes a closer look at the progress of the land reclamation at the Carbon Junction Mine on Tuesday.  The mine is using the unconventional method of mycorrhizal fungi to restore the balance of the ecosystem and native vegetation that once inhabited the area. The fungi is a sort of natural fertilizer, acting as an extension of the plants’ roots, helping to bring in more nutrients./Photo by Todd Newcomer

by Adam Howell

Environmental stewards are giving land reclamation a new meaning in Durango, and they are doing it with a technology that’s been around longer than humans. Throughout the county, mushrooms are undoing damage to the land.

Companies are now acknowledging the environmental and financial benefits of directly implanting prefabricated fungi into the soil. Mycorrhizal fungi, specifically, is gaining recognition for developing a relationship of nutrient dependence between the structures of the fungi with the roots of seedlings. Radiating out from the roots, these filaments attach and penetrate to the roots’ outer layers, acting as extensions of the roots.

Scientists say the fungi benefit the host plant by increasing water and nutrient uptake and protecting against diseases; likewise, the plant helps the fungi by providing carbon. It’s an organic reclamation process in stark comparison to practices marked by chemical fertilizers and large-scale water pollution.

At the reclamation site of Four Corners Materials’ old gravel pit on Ewing Mesa, mountain bikers and hikers can curiously eye the cosmeticized scar left from the mine. Lacking trees, the barren, 64-acre plot is a thoroughfare for inhospitable winds.

After the gravel mine was scored for its gravel for several years, the surrounding mounds of desiccated, slightly sterile soil were used to resurface the contoured landscape.

Once the surface was smoothed out, Marcia Talvitie, the company’s environmental/resource manager, hired James Ranch Landscaping to inseminate the site with grass seeds and mycorrhizal fungi. For the reclamation, Talvitie’s goal is to tackle the root of the problem and establish native grasses and fungi that once inhabited the area.

Using fungi is a financial risk worth taking for Talvitie. It costs about the same per acre as chemical fertilizer; at the same time the success of plants in the area could determine whether a hefty portion of Four Corners Materials’ bond payment to the Colorado Division of Minerals and Geology will be returned.

“It seems appealing to use something organic rather than some chemically manufactured fertilizer,” she says.

On the Ewing Mesa project, Talvitie continues to chart ecological progress with the passage of each month. Next year, James Ranch Landscaping will dig up a specimen and send it to its supplier, Mycorhizal Applications, Inc., to determine the scientific success of propagation and various plants, according to former James Ranch Manager Michael Freeman.

For people using the adjacent Carbon Junction Trail, the project’s success could mean extending the life of surrounding piñon trees. That’s because the fungi can also serve as antibiotic organisms for piñons, thus fending off bark beetles, Freeman says.

Diverse fungal networks in the ground act as the immune system for the forest, agrees Fort Lewis College’s campus ecology coordinator Dean Mullen. These naturally occurring mycelial mats helped spur the idea to produce antibiotics like penicillin in huge warehouses.

Mullen explains how fungi have to seek out their food and then produce digestive enzymes, saying, “It would be like us barfing on our food, letting it break down

Michael Freeman checks  the progress of the fungi reclamation at the old Carbon Junction gravel mine. The fungi is a more environmentally friendly alternative than chemical fertilizers./Photo by Todd Newcomer

from the acids, and then sucking it up with a straw.”

Mullen did his senior research on the role of fungi in breaking down mulch by studying how fast white rot fungi would help lower the acidity level of the soil beneath it.

Mullen hopes his skills dealing with waste at school will transpire into a career with fungi as the foundation. In the meantime, he says the single best thing people can do to foster growth of fungi in the soil is to throw down a thick layer of mulch.

While the local use of mycorrhizae has its benefits, Mullen offers words of caution to those who experiment, saying that foreign fungi can be detrimental to our environment. Julie Korb, an assistant professor in the4 biology department at FLC who studies plant ecology, concurs, saying that a lone species could interrupt the natural ecosystem in large-scale restoration projects.

In contrast, people growing gardens or other small-scale landscaping projects could help their plants by applying a single species of mycorrhizae, she said. Of the hundreds of species, Korb stressed the use of native species in topsoil that’s been set aside.

Although recent studies have indicated that in some cases a particular plant must be associated with a particular fungus, it is important to note that many are found globally, according to Korb. In addition, studies have shown mycorrhizal fungi to not always be mutualistic, but rather parasitic. Therefore introducing one or a handful of mycorrhizal species to the landscape may benefit some host plants and be detrimental to others.

Both native and non-native plant species will benefit from mycorrhizae, as well. Some recent studies have found that mycorrhizae have assisted exotic plant species, such as knapweed, to out-compete native plant species, Korb says.

“The introductions of Russian Olive and Tamarisk to the western United States are good examples of what can go wrong when we introduce non-native species into native ecosystems,” she said. “The main lesson from these introductions is that we need to proceed cautiously when introducing any new species into an environment.”

In agreement, Michael Amaranthus, owner of Mycorrhizal Applications Inc., in Oregon, says that using native, diverse mycorrhizal species is an important factor to successful root growth. A single species of mycorrhizal fungi can form with thousands of different plant species. For example, less than 200 species of endomycorrhizal fungi are known to form with more than 400,000 species of plants.

By borrowing from nature’s template, more than two dozen universities have tested his mycorrhizae products with successful results over the last couple of years, he said.

What scientific testing found was the amount of mycorrhizae that grows correlates well with the vigor of the plant, he said. As a consequence, people can use less fertilizer and water.

Further benefiting customers, he said, is their ability to later determine what percentage of the root length is colonized with the mycorrhizae by sending a root sample to their laboratory.

Whether its use is for ecological restoration, agriculture, horticulture or simple gardening, the consensus among land stewards is that fungi are the underrated lifelines of all plants.

“We really want to take the muck and mystery out of mycorrhizae,” Amaranthus says.

Mixtures of various mycorrhizal species can be purchased locally at Durango Nursery and Supply and online from Mycorrhizal Applications, Inc. at www.mycorrhizae.com. •