Finnriver Farm & Cidery Journal
Collaborating with plants, bacteria and fungi to clean our soil
That patch of yellow-flowering, wild mustard greens behind the Finnriver Kitchen aren’t just growing tall to look pretty; they’re working hard! Results are in from the first round of testing on our bioremediation project, revealing the decontamination efforts are meeting our goals of clean and healthy soil!
The Remediators, one of Finnriver's land partners, took up the task of removing toxic levels of petroleum and lead from an area of the property where farm equipment was historically repaired. A network of specially selected plants, bacteria and fungus (locally sourced willow, rapeseed, PDN-1 bacterial endophytes, and a mushroom strain similar to the edible Stropharia rugoso-anulata) have significantly reduced the high levels of toxins detected on the site since the project began two years ago.
In a decontamination method known as the Integrative Biological Approach, mycoremediation and phytoremediation are used in tandem to leverage each organism’s purifying talents. These living beings have proven abilities to grow in contaminated soils and take up or break down petroleum and heavy metals.
“By combining this suite of organisms together, they work better than on their own,” said Howard Sprouse, CEO of The Remediators and lead of the project at Finnriver.
For example, the chosen fungi strain are able to transform heavy metals into a soluble form that the plants can then take up and store in their tissues. In general, the methods of bioremediation transform toxic organic materials at the molecular level, converting them into more innocuous compounds. While full mineralization of contaminants is desired, it is sometimes not possible, as in the case of heavy metals. In these scenarios, the hyper-accumulating plant material can be removed from the soil and taken elsewhere to decompose. This will be the method utilized at Finnriver. The biomass of the plant and fungal matter will be significantly less than if the contaminated soil were to be removed directly, as is the case in more conventional forms of remediation.
In some cases, the plant or fungi material utilized in remediation create useful byproducts, such as bio oils that can be turned into fuel. There is even consideration that edible mushrooms can be harvested as a food crop byproduct in instances where the organic soil contaminants might be decomposed without so imparting toxicity.
Soil contamination, particularly involving heavy metals and petroleum, pose huge health burdens to society and to the earth. Conventional clean-up invokes a sizable financial strain as well. Through observation, appreciation and application of the natural capabilities of some specific plants, bacteria, and fungi, we can remediate the damage as we work in partnership with these incredible beings.
The samples collected from the Finnriver farm this spring were from areas of the project where plants were growing well and that were expected to be cleaner. More complete testing will occur at the end of this year’s growing season.