By Brandy Harrison
GUELPH — With blue-green algae blooms in Lake Erie making headlines and reduction targets already on the table, phosphorus runoff is shaping up as the next hot-button issue, says the chair of the Grain Farmers of Ontario board.
“Maybe 2016 will be the year of phosphorus,” Mark Brock says, adding that now that official targets are in play, agricultural restrictions can’t be ruled out, especially with neonicotinoid seed treatment regulations fresh in farmers’ minds. “It would be naive to think that there isn’t some regulation coming down the pike. No matter what, the status quo won’t be an option.”
Phosphorus, which encourages algae growth, shot up the government priority list when blue-green algae blooms in Lake Erie left half a million Toledo, Ohio residents without drinking water for two days in August 2014.
Last June, Ontario, Ohio, and Michigan signed the Western Basin of Lake Erie Collaborative Agreement, committing to reduce the phosphorus load in Lake Erie to 40 per cent below 2008 levels by 2025. It supports the Canada-U.S. Great Lakes Water Quality Agreement and Ontario is working with both federal governments to set targets by year’s end.
While municipal sewage treatment plants and industrial and urban runoff play a part, agriculture is also under the microscope.
Farmers have long taken for granted that applied phosphorus was tightly bound to the soil, blaming surface runoff and soil erosion for losses, but dissolved phosphorus also leaches through tile drains, mostly outside of the growing season.
A 2012 Ministry of the Environment and Climate Change study of 15 streams in a primarily agricultural watershed found runoff varied from 20 to 190 kg per square kilometre per year. But on average, Ontario runoff is lower than in the United States, says a ministry spokesperson.
No matter the farm share of the blame, change is coming and farmers have to be proactive in refining application strategies, says Clarence Nywening, Christian Farmers Federation of Ontario president.
“Farmers will be the easiest ones to start picking on because we put it directly on the ground,” he says.
Best management practices may not get farmers there quickly enough, Brock says, adding they need more research to understand phosphorus movement and the most effective retention methods. They’ll also need funding for infrastructure and management changes.
The agriculture sector should be given credit for what it’s already done, says Neil Currie, Ontario Federation of Agriculture general manager.
Farmers have got on board with the Environmental Farm Plan, nutrient management planning, and more recently, the 4R program, which emphasizes using the right fertilizer, at the right rate, the right time, and in the right place.
“Everyone knows it doesn’t pay to over-apply fertilizer,” says Currie. “As we’ve seen, the Ontario government tends to be predisposed towards regulating. We have a good case for heading off regulation. Farmers have voluntarily taken action. There should be faith that farmers will continue to do that.”
Ohio farmers already have marching orders. Fertilizer application requires certification by September 2017 and fertilizer or manure application on snow-covered, frozen, or saturated soil is banned with civil penalties ranging from $2,000 to $10,000 per day. Farmers have to keep a record of dates, times, rates, and methods of application as well as soil and weather conditions, says Ohio wetland and soil consultant Frank Gibbs.
“The legislature already passed all these rules before we’ve even got the data on why dissolved reactive phosphorus is coming loose from the soil,” he says. “We can’t wait. Our rear ends are on fire in Ohio.”
Reduction requirements in Ontario aren’t yet clear, but a joint action plan released in September by the Great Lakes Commission similarly recommended farmers reduce high-loss risk applications outside of the growing season, soil test and use crop-specific agronomic application rates, and adopt 4R programs. The report also recommended jurisdictions pilot outcome-based incentive programs that pay farmers to meet specific environmental targets.
OMAFRA says reduced tillage, longer crop rotations, and cover crops can also increase water absorption and banded fertilizer phosphorus is more effective than broadcasted.
Farmers need a whole tool chest, Gibbs says, including water control structures in drainage systems, more frequent and lower rates of fertilizer, variable rate application, and improved soil health from good aggregate stability to increased organic matter. Adopting one practice isn’t enough, he says. “There is no silver bullet.”
There are hopeful signs, Brock says. Unlike with neonic-treated seeds, farmers are part of the conversation.
“It’s encouraging that it’ll happen with a more bottom-up approach. If the provincial government says ag has a role, I’m not getting hung up on numbers. Whether we want to or not, they’re looking for a solution from our industry and we have to take that seriously.”