Tree plantations can be part of land reclamation projects but also produce the raw ingredients for a variety of products
A scientist says willow plantations can potentially turn marginal land into a renewable source of everything from fuels to plastics, sparking a new type of agriculture for Western Canada, while enriching the soil.
“That is absolutely the goal,” said John Lavery, senior scientist and business development manager at Sylvis Environmental Services Inc. “We fully anticipate that by the end of our process, class four and five lands will have achieved class one and two in terms of productivity potential.”
As part of the $10.5-million Biosalix project, willows will help reclaim a demonstration site at the Paintearth surface strip coal mine near Forestburg, Alta., northeast of Stettler. Westmoreland Mining announced earlier this year it will be closing Paintearth, whose only customer, the Battle River Generating Station, is switching to natural gas to produce electricity.
Besides $1.5 million from Alberta Innovates, the project will receive $3.8 million from Natural Resources Canada’s Clean Growth Program and $2.1 million from Emissions Reduction Canada. Other funding and in-kind services are being provided by Sylvis and Westmoreland, along with Epcor Utilities Inc. and Bionera Resources.
Biosalix will use treated and stabilized biosolids derived from sewage or waste water processed at the Edmonton Waste Management Centre. They will be used to help create and fertilize topsoil at the demonstration site, which is slated to cover 1,235 acres.
The willow plantation will consist of thousands of plants per acre, which will be grown in rows so they can be raised and harvested using modified agricultural equipment, said Lavery.
Although such plantations have been providing feedstocks in countries such as Sweden for more than 40 years, and have been under development in Canada for more than 20 years, the scale of the operations by Sylvis is new for North America, he added.
“Canada has relied on its natural forests for its sources of fibre for dimensional lumber, but also for paper and energy and other products. But this is a way for us to start expanding the agricultural value chain to materials that are beyond the traditional cereal and oil crops.”
Potential products range from biodiesel and renewable natural gas to ethanol, “all of which are important precursor materials to be able to do any number of things as a direct replacement for petrochemicals — so we can produce bioplastics, we can produce biofuel, we can use the material for heating energy, we can produce alternative fertilizers or biochars to further enhance soil organic matter and soil quality.”
The federal government plans to phase out coal-fired electricity by 2030. Although Biosalix is aimed at remediating things such as former surface coal mines, willow plantations could potentially be grown on any type of marginal land depending on the local climate, said Lavery.
Sylvis is involved in an 865-acre plantation near Keoma, Alta., that has been using municipal biosolids from the nearby City of Calgary, he said. The project, which is on land owned by the Mountain View Hutterite Colony, has plans to expand by 445 acres.
Such plantations are already being put to uses ranging from providing a bulking agent for composting by the City of Calgary to forage for animals such as moose and caribou at the Calgary Zoo, he said. “To my knowledge, the plantations in Alberta are the largest operational plantations in in North America.”
Farmers will earn revenue from things such as leasing their land and providing labour and equipment, but Lavery expects soils will also be enriched during the 25 to 45 year lifespan of such projects so the land can support conventional agriculture.
“And so, perhaps an interesting future vision for how we undertake agriculture throughout the Prairies is we cycle into these long-term, financially productive fallow systems that use a species like willow to re-energize and re-carbonize our soil.”
The willows have little in common with the willow thickets that dot the Canadian prairie, he said.
“They’re almost unrecognizable, so we use very specific varieties to achieve growth to very quickly occupy the entirety of a site to reduce the need for weed management.”
The plantations also differ from the ornamental tree nurseries grown by farmers because the willows can be repeatedly cut and harvested without killing them. Lavery likened the harvesting process to “mowing a big woody lawn, and in the spring that root stock … then produces shoots again from its base.”
Such abilities mean the plantations will sequester carbon, which is a vital factor in the fight against climate change, he said. Although harvests can take place every two to four years, the “magic number in Alberta” seems to be three years, with about a third of each site harvested annually and then fertilized with municipal biosolids, he added.
Besides providing fertilizer that will boost the plantations’ productivity, the use of municipal biosolids and waste water also potentially means communities such as rural towns faced with increasing populations won’t have to expand things such as waste water lagoons, he said.