A soil test always provided basic but necessary information: the levels of important plant nutrients principally nitrogen, phosphorus, and potassium; pH readings, is the soil too acidic and needs lime; soil organic matter levels. Now the provincial agriculture department is offering something much more comprehensive, a soil health test. It’s a bigger change than most people realize.
I can think of a half dozen conversations over the last forty years with agriculture officials here and elsewhere, including a deputy minister, where it was strongly argued that soil was nothing but trouble. Its makeup was inconsistent, and most seriously, it harboured diseases. They argued that farmers would be better off if seeds went into sand, and they could carefully apply just the right mix of chemical fertilizer and pesticides.
The idea that soil can be trouble continues to this day. Fumigation, pumping a gas like chloropicrin into the soil which essentially sterilizes it, is widely used in western U.S. potato growing areas, and occasionally here in the Maritimes to produce disease-free strawberry and other fruit plants for example. McCain Foods has conducted soil fumigation tests on potato farms in New Brunswick and Maine. Here on PEI, to their credit, potato growers have resisted fumigation to fight wireworm, instead mostly relying on brown mustard as a bio-fumigant.
I feel a little like my grandmother insisting that we eat our vegetables in making a case that maintaining healthy soils is important. Management tools like chemical fertilizer and irrigation have allowed farmers to maintain productivity as soil health declines, but the environmental costs of anoxic waterways, nitrates leaching into drinking water, and groundwater resources threatened worldwide have made improving soil health a priority wherever industrial scale agriculture is practiced.
I firmly believe farmers know this. A marketplace dominated by a handful of processors and wholesalers has made it difficult for too many farmers to make enough money to support the crop rotations needed to maintain or rebuild soils. Cash has to be generated every year, so corn and soybean are grown in rotation with potatoes rather than the no-income forages which would improve organic matter levels. Serious research is being done to help farmers find practices and crops that will improve this, and the new soil health test compliments this effort.
The presentations by Kyra Stiles and Bradford Rooney of the Sustainable Agriculture section made to farmers around the province showed how much more information is available now: not just soil organic matter levels, but active vs. stable carbon, soil respiration, aggregate stability, inorganic and organic nitrogen levels, phosphorus and other nutrients availability, and soil pH. They clearly explained that all of these work together to create healthy soils, capable of holding moisture, provide necessary nutrients, and when combined with reduced tillage and cover crops, reduce wind and water erosion. The soil is described as something living with microbes, bacteria and fungi, a welcome change from the “soil is only trouble” crowd.
There’s another important element to this. The baseline data used to judge whether organic matter levels for example are high or low don’t come from some ideal farm somewhere else in the world, but from data collected on PEI over many years. Results are always handled anonymously, but farmers will be able to track changes in their own soils over time, and have some idea how they compare with other farms in the province.
Two things I think are driving the increased level of research into rotation and cover crops, this new soil health test, and the ongoing development of Best Management Practices. The results from province wide test sites monitored over many years have shown a serious decline in soil organic matter levels. Secondly farmers are looking for some clarity on what constitutes “due diligence” when it comes to preventing fish kills.
Court rulings have been inconsistent on what practices can reasonably be expected from farmers to prevent fish kills given severe localized rain events caused by climate change. Soil building, taking steps to prevent erosion, all add credibility to the “due diligence” defence.
This isn’t easy for farmers. Critically examining current practices on farms, changing rotations, considering the purchase of new equipment to limit tillage, all so soil health indicators like organic matter levels will improve slowly over many years, is a very challenging proposition. Think of going to your doctor and being told that blood pressure and cholesterol levels are dangerously high.
Your told to start eating a much more expensive diet, get a costly gym membership, and buy an expensive new car to get there. It will save your life, but it’s a difficult message to swallow. The soil health test (free for now) is like that visit to the doctor, challenging, but it’s how things, including yields, quality, profitability, and the environment, get better.