State of the soil
P.E.I. measures appear to be stopping declines in soil organic matter
Editor’s Note: The theme for this year’s Earth Day is “Restore Our Earth” and recognizes that while climate change is a big concept, there are small things we can each do to help. This week, we’re looking at ways that Atlantic Canadians can make a difference, right here at home.
Vernon Campbell believes there is always going to be a trade-off in terms of soil health and farming.
Where there is farming, there is tillage of the soil, says Campbell, whose potato, beef and dairy farm is based near Summerfield, P.E.I.
“With potatoes or any vegetable crop, you can’t not till them. There’s got to be a certain amount of tillage,” Campbell said.
“Tillage is the enemy of organic matter.”
Campbell, a member of the board of directors with the Soil Conservation Council of Canada, tries to minimize the loss of soil organic matter in his own operation. He’s replaced a moldboard tiller with a cultivator that only turns some of the sod over in the fall. He also plants winter rye as a cover crop after harvesting potatoes, mitigating against the loss of soil.
As a beef farmer, he is also able to use barley and forage crops for his livestock, while using manure produced on hand for potatoes.
“I’m basically doing what my grandfather did 50 years ago, only on a much larger scale,” Campbell said.
Like a growing number of farmers in P.E.I., Campbell employs these practices in order to help arrest a precipitous decline in soil organic matter observed in P.E.I. over the last two decades.
Recent dry growing seasons, such as the drought-like conditions seen in 2020, have driven home the importance of rehabilitating soil health in the province. Soil organic matter helps improve water holding capacity in the soil.
In 2017, a paper in the Canadian Journal of Soil Science found that, between 1998 and 2015, fields with between three and four per cent of soil organic matter declined from 70.6 per cent to 24 per cent of the total landmass of P.E.I. Acreages with between two and three per cent of soil organic matter increased from 10 per cent to 73 per cent of the Island’s total land area.
A number of factors have brought about these declines. The naturally coarse texture of P.E.I. soil, along with the often high rainfall amounts throughout the year, contributed to erosion. Declines in the livestock sector also reduced the amount of manure available to farmers. Other practices, such as more intensive tillage or a lack of cover cropping have played a role.
But as of last summer, the most recent data collected by staff working with the P.E.I. Department of Agriculture and Land found that soil organic matter has not gotten worse between 2015 and 2018.
“The way I would interpret it is relatively unchanged from 2013,” said Judith Nyiraneza, one of the authors of the 2017 paper and a research scientist with Agriculture and Agrifood Canada.
“We need a few more years to see if we really will reverse the trend.”
Nyiraneza has found that the stabilization of soil organic matter in P.E.I. has been due to the adoption of a number of best management practices employed by farmers like Campbell. These include the use of winter cover cropping such as rye or mustard, the use of manure and soil amendments, reduced tillage, increased use of green manure and foreage crops within crop rotation and erosion control methods.
A survey from the P.E.I. Potato Board found that more potato farmers are employing practices to arrest declines in soil health.
In a 2019 survey, 57 per cent of respondents said they planted more cover crops in 2019 than the previous three years. Following the 2020 growing season, this had increased to 73.5 per cent.
“The No. 1 type of question I get from potato farmers relates to crop rotation and how they can optimize their rotation to improve soil organic matter and reduce soil-borne disease,” said Ryan Barrett, an agronomy specialist with the P.E.I. Potato Board.
P.E.I. is not alone in terms of its struggle with rejuvenating its soil.
“P.E.I. is actually quite representative of Atlantic Canada and to some extent Eastern Canada,” said Dave Burton, a professor with Dalhousie University’s Department of Plant, Food and Environmental Sciences.
“It’s very different from prairie Canada. And that’s because of climatic differences.”
But Burton said P.E.I.’S 20year practice of tracking soil health could be considered a success story.
“Most other provinces aren’t bothering to do that,” he said
“But that doesn’t mean it’s a greater problem than somewhere else. It’s just that you know more about it.”
Still the declines in soil organic matter have produced significant criticism in P.E.I. from groups like the National Farmers Union. Speakers at a annual meeting of District 1 of the NFU in Summerside pointed to the practices of potato giants like Cavendish Farms as contributing to the declines in soil health.
Other organizations, including the P.E.I. Potato Board, have said criticism likes this unfairly demonizes farmers, who are often employing proper soil health measures.
“The National Farmers Union are right in flagging that. But it’s also — particularly in the farming community — it’s not very productive to say the sky is falling,” Burton said.
“You have to point to things that are working and to try to help producers slowly change their practices."