This fall, a new sort of buoy will be bobbing in the water in Downeast Maine. Not made of plastic, not made of wood, the new buoy is made of a surprising material: mushrooms. Abby Barrows at Long Cove Sea Farm and Severine von Tscharner Fleming at Smithereen Farm are trying out mushroom buoys this summer at their respective aquaculture operations. In addition, the new buoys will be tested in Walpole at the Darling Marine Laboratory and in West Bath at Winnegance Oyster Farm.
“Smithereen Farm and I got a grant last year to kick off this work,” explained Barrows in an email. “Now I am operating under another grant, building upon our work last season. I wanted to be able to have gear be trialed in different areas of Maine in order to see how things held up under different environmental pressures.”
The newfangled buoys are a first step toward reducing the amount of plastic used in the marine environment. Plastic is a problem. It’s made from petroleum and is designed to be flexible and strong. It also has a very long life. NOAA’s Marine Debris Program estimates that a Styrofoam cup will take 50 years to break down in the ocean; a plastic bottle will take 450 years; and fishing line will take 600 years to degrade.
Even then, the plastic is not actually gone. In the ocean, plastic items exposed to sun, salt, and battering by waves break up into smaller and smaller pieces, called microplastics. Microplastics are plastic particles smaller than five millimeters across. Even when a plastic bag or bottle is gone from sight, the plastic itself is not gone from the ocean.
Now there is a material that could be a substitute for plastic. In the early 2000s, two engineering students at Rensselaer Polytechnic Institute, Eben Bayer and Gavin McIntyre, invented a substance that they called Mushroom Material as part of a senior project. In 2007 they founded their company, Ecovative, to grow this material as a substitute for plastic. Mushroom Material has proved to be strong, insulative, flame-resistant, and, important for fishermen, buoyant.
The material is made of the “roots” of mushrooms, called mycelium, that are grown on plant waste. The mycelium push into the plant waste and begin to digest it. As mycelium grow, it creates a strong, foam-like mass which is lightweight and non-compressible. Mushroom material can be grown in any shape desired and takes just about a week to make.
One product that Evocative makes is custom packaging called MycoBond™ which can replace the typical Styrofoam used to pack computers, TVs, and other delicate items. MycoBond™ is made with hemp fiber waster and mycelium. Evocative can “grow” a custom EcoCradle that is specific for any product. Once it is finished as a packing container, it can be broken into smaller pieces and put in the compost pile or left outside to decompose. Testing conducted by NOAA showed that the EcoCradle withstands prolonged exposure to tropical shipping conditions and sea spray and yet will break down in in less than five months.
This spring, Sue Van Hook, who worked for Evocative, came to Maine to promote the use of MycoBond™ to make buoys. According to an article in the Bangor Daily News, Van Hook has tested buoys made of the mushroom material along the east coast for years. The problem was finding a waterproof coating not made of plastic that could keep the buoys whole throughout the season. Recently she worked with a chemist who has come up with a biodegradable, non-toxic coating that will be used at the two aquaculture sites this summer.
“We had wanted to get them in the water earlier but the oyster seed was only ready last week [mid-August],” Barrows said. “I will leave some of the prototype gear in over the winter.” If mushroom material turns out to have staying power, a different type of buoy might be bobbing along the Maine coast next year.