Managed grazing improves soil quality, sequesters carbon from the atmosphere, and provides the soil biology with increased food and shelter. Gillian Watt, owner and farmer at Holmwood Farm and program coordinator of the Applied Sustainable Ranching Program at Thompson Rivers University provides her insights on BC’s livestock sector. Watt believes, “Regenerative agriculture is one of the main answers to climate change.” In our video below, Watt explains how she rotates her animals and the impact they have on the land. A component of regenerative livestock farming, Watt explains, is moving the animals in a way that reduces the need for external inputs. She says, “Part of the idea of having the cattle and the sheep together is called mob grazing, if [the sheep] have been on an area of land over a number of years, they get parasites. To reduce parasite load, it’s good to mix the cattle and the sheep together because the cattle will graze the sheep parasites and the sheep will graze the cattle parasites, reducing the overall parasite load in the soil without it affecting the cross animal.” Animal health is crucial, not just for the sake of on-farm revenue, but for a healthy, climate-friendly farm. Watt gives an example of a presentation from a student in the Sustainable Ranching Program. “One of our students presented at the Cariboo Soil Health Conference in January 2020, where she showed a picture of different cow pies. First, she showed the one that was from an animal that had not been given parasite control recently. It showed that there were holes all through the cowpie, which was from the dung beetles. From this student’s experience, what they found is that the animals that they bring in for custom grazing that have been given parasite control, do not have the dung beetle holes, so they do not break down as fast and a link in the chain is removed. So the cows that don’t have that [parasite control] in their system, these dung beetles are just tearing up [the manure] and distributing it out really fast.” The mob grazing technique also helps to reduce the parasite load naturally, eliminates the need for external inputs, and invites other forms of life that contribute to regenerating the land. There is no waste in these systems, “Everything that these animals eat, it just goes back into the soil,” says Watt. “So even when we hay this land, we bale graze this area in the winter. What the sheep and cattle trample is not waste, it’s going back into the soil as organic matter. We really look at areas in the field that are higher and thinner in organic matter depth, and that’s where we try to place the bales for bale grazing.”
In intensive rotational grazing practices, grasslands are able to capture carbon and increase soil biodiversity. Dr. Lauchlan Fraser, who studies the effects of rotational grazing on BC’s grasslands, explains why having cattle on a grassland positively impacts the area. He says, “When a cow chomps on the grass, it continues to grow at its base. Depending on the species of grass, the growth rate is actually stimulated. There’s an increase in the rate of growth in the individual plant that is grazed. There are also excessive roots, that are in excess of what is needed to support at that point in time the above-ground tissue, the leaves. So, there’s a grazing event, a bunch of grass leaves are eaten, there’s a stimulation in growth as a response and then there’s a sloughing of root material to balance that above-below ground ratio. That rooting material, a lot of it will certainly decompose and even be eaten by nematodes but a portion of that does go into the soil organic matter”. Fraser explains that the response is compensatory. He continues, “It compensates for the disturbance and it increases growth so it increases productivity overall. If you can balance it properly, you can potentially maximize carbon sequestration through that whole process.” While his research is long-term and the team is still understanding the effects of this process, they have noticed some differences between regions. Fraser says, “We have tested this across many different grassland types across British Columbia, it seems like mean annual precipitation can influence the response. Wetter grasslands are more likely to respond positively to grazing as a stimulus for carbon sequestration and dryer grasslands less so.”
“I think a well-managed grassland can definitely include a cow.”
One project that Fraser’s team is working on is a silvopasture project, with a partial focus on carbon sequestration. Silvopasture is a technique of farming that integrates trees and grazing animals in a way that is mutually beneficial for the animals, trees, and the environment. The goal of Fraser’s project is to test and compare forest systems to pasture systems and their capacity to sequester carbon. Fraser notes that this research is ongoing but, “Some preliminary evidence suggests that grasslands store just as much carbon overall compared to forested systems.” He explains, “When you look at a grassland there’s not a whole lot of carbon above ground. Most of that carbon is below ground and the advantage of that, of course, is that below ground carbon is more stable. Forests are susceptible to major disturbances like our forest fires that we have been experiencing. So all of that so-called stored carbon is suddenly gone. The particular silvopasture system that we are working with uses strip thinning, so it’s not selective logging it’s actually running basically strips in the forest. The tests that we are applying is strip thinning at various widths. We’re basically testing whether the width of a strip influences forage productivity and carbon sequestration in the soil. These widths are not large, they’re 10 or 15 or 20 meter strips in the forest. An interesting side angle is that these strips can likely serve as fire breaks and so I think there could be some really novel ways of working with these two different industries, collaboratively.” Many livestock farmers in BC practice this technique, one being Lost Savanna Farm on Vancouver Island. Britt and Kris Arbanas own the 73 acres, certified organic and biodynamic farm, and strive to produce food that is both nutritious and farmed in a way that regenerates the land.
Grasslands are a critical ecosystem in BC and across the world. Fraser explains, “looking globally, about 24% of the land base is grasslands, in BC less than 1%. They provide habitat for 30% of rare and endangered species.” Cattle and livestock are an important component to the health of our grasslands, here in BC and around the world. Managing livestock on grasslands stimulates growth and enhances diversity. “No matter what the grassland type, if it’s grazed, then plant diversity is going to increase. So, Fraser says, “I think a well-managed grassland can definitely include a cow.”
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