In the July 24 edition of columnist Paris Reidhead’s “Crop Comments” (available at CountryFolks.com), he noted that switchgrass, a source of cellulosic ethanol, is “drawing favorable reviews from the sustainable science community, because it’s a perennial crop. This fact alone absolves it from the guilt of greenhouse gas creation associated with intensive tillage so prevalent with annuals.”

That cellulose is a perennial powerhouse. Cellulose is a molecule consisting of hundreds (sometimes even thousands) of carbon, hydrogen and oxygen atoms. It’s the main substance in the walls of plant cells, helping plants to remain stiff and upright. That strength is being taken advantage of more and more often in food, fiber and other products.

Discussing the multiple uses of perennial grasses at this year’s American Forage & Grassland Council annual conference was Sam Jackson, vice president of feedstocks and supply and chair of Genera. Founded in 2008 in Tennessee, the company focuses on the biomass supply chain for downstream players.

(The homepage of their website reads “We Make Cool Stuff From Grass. We grow carbon-negative grass fiber and turn it into compostable packaging and bioproducts. Used by brand owners and consumers, the cycle continues through composting, returning nutrients to the soil to begin anew.”)

Jackson homed in on the potential of agricultural fibers. “Virtually every product made from oil can be made from ag fibers,” he said, listing dispersants, towels and tissues, foodservice disposables, food packaging, paperboard, medical disposables, pharmaceutical packaging, textiles and fabric, absorbents and adsorbents, animal feed and more. And all these products are fully compostable and biodegradable.

Switchgrass and miscanthus are the primary grasses being utilized in this industry, as they’re high yielding, drought resistant, offer year-round supplies, have minimal management intensity and are regenerative, according to Jackson.

Growing them for products like these enhances rural economic development, which can be seen in “increased farm market diversification and opportunities, improved market security for farmers and landowners and job creation through manufacturing facilities,” he added.

Swapping other sources for switchgrass

Switchgrass offers a lot of opportunities. Photo courtesy of Brett Hampton, University of Nebraska, Bugwood.org

Jackson expanded on this idea by stating that purpose-grown agricultural fibers like these support rural economies because they don’t compete with food crops and they offer new and/or additional revenue sources for farmers, often in the form of stable farm income from long-term contracts.

These perennial grasses also produce high quality products. Jackson said they boast superior product performance, often exceeding industry standards for tensile strength and protection again tearing and bursting.

They also achieve sustainability goals, as crops like switchgrass sequester carbon and improve soil quality. They preserve green space and wildlife habitat as well.

With sustainability goals becoming more prevalent, productivity and carbon metrics are key. “A lot of land is underutilized in the Southeast and these grasses make good fibers,” similar to hardwood fibers, Jackson said. (Switchgrass can be found growing as far north as the Canadian border too.)

For farmers looking to diversify while also helping the planet, perennial grass fiber’s sustainability is driven by reduced inputs, carbon uptake by the plants, soil organic carbon increases, reduced land use impacts and reduced freshwater use impacts.

But wait – there’s more. According to Jackson, these grasses have other markets, including liquid fuels such as sustainable aviation fuel and ethanol/methanol, etc., as well as renewable natural gas, which comes from anaerobic digestion) and poultry bedding (as an alternative to wood shavings, and with better manure/ammonia absorption, poultry litter can be directly applied or composted and applied to land as a nutrient source).

Switchgrass and the like are also good for erosion and stormwater control, as they can absorb more than twice their weight in moisture. The grasses can be used in building materials (as supplements to concrete and asphalt production). And they can provide fiber supplements in pet food. Jackson mentioned MFiber LLC as one pet food company utilizing perennial grass fiber today.

“Performance and sustainability drive interest,” Jackson concluded. “The more widespread use of perennial grasses for consumer products will create strong opportunities for agriculture to continue to positively impact farmers, the environment and society.”

by Courtney Llewellyn