Reducing Tillage for the Climate

Posted on Tuesday, 1 November 2022 under Supporting Farmers and Ranchers Feature

Turning over the soil to control weed and pest pressure and preparing the ground for seeding is a long-standing farming practice. Intensive tillage, however, increases soil erosion leading to nutrient runoff and the release of greenhouse gases into the atmosphere. Though tilling is often vilified, it is important to consider that tilling is a necessary practice for many farmers in BC. To help farmers have healthier farms and limit environmental damage, tilling can be done less intensively.

 

Reducing tillage is increasingly recognized as a climate solution and a beneficial practice for soil health, minimizing soil disturbance and targeting goal-specific benefits for farmers. Share on X

Reducing tillage is increasingly recognized as a climate solution and a beneficial practice for soil health, minimizing soil disturbance and targeting goal-specific benefits for farmers. This practice often means tilling with less intensity at a shallower depth, resulting in a less disturbed area overall. Reducing tillage is recommended to decrease soil erosion and runoff, increase soil productivity, and lessen production costs. Given the reduction in energy inputs and soil disturbance, this practice has quickly become a climate solution in agriculture and is often referred to as conservation tillage. Decreasing soil disturbance reduces carbon dioxide and greenhouse gas emissions, leads to less reliance on farm equipment and heavy machinery, and an overall reduction in fuel and energy. The practice of reduced tillage or conservation tillage, is a beneficial climate strategy and provides long-term benefits for farmers.

Soil scientist Matthew Kyriakides describes tillage as destructive to soil health. Kyriakides specializes in agroecology and restoration ecology. He is working on a PhD with the Ecogastronomy Research Group at the University of Victoria and holds a BSc in Global Resource Systems from UBC and an MSc in Earth and Environment from Wageningen University & Research in the Netherlands. As the Manager of Land Resources at the Sandown Centre for Regenerative Agriculture, prioritizes working with local communities to create regenerative systems that benefit us all. The Sandown Centre, located on the traditional lands of the WSÁNEĆ peoples, delivers food production, programming, and research with a focus on ecological health. Their mission is to steward biodiversity, foster growers, and engage the community.

“There are a lot of good reasons why people want to [till],” says Kyriakides. Tilling is an important practice to manage weeds and pests, and gives farmers an easier surface to seed into. Kyriakides describes the payoff as short term; microbes can feast from the initial oxygen and room added to the soil. However, the soil recompacts over time, resulting in a need to till again. He explains, “One of the things that is damaging with tillage is looking at things like mycorrhizal fungi – these are creatures that are forming a symbiosis with plants. They are so much smaller than the plant roots. They are basically like a web that can go and gather nutrients and water and bring them into the plant in exchange for carbons and sugars.”

Kyriakides emphasizes how important these fungi are. He says, “[Fungi] are a really important way that plants access the resources that they need, but they are also very sensitive to disruption. When you till, you break up those fungal hyphae, those mycorrhizal connections, and it takes a bit of time for them to start to establish again.” Tillage promotes short-term relief when dealing with weeds but disrupts important ecological communities within the soil. Kyriakides says tillage is, “A way to just make a more simplified, homogenized system, treating the land as a commodity rather than a partner in this very delicate dance that agriculture is.”

The relationship between plants and soil microorganisms is crucial yet complex, tracing back thousands of years. Kyriakides explains the relationship between the two, saying, “Plants produce sugars and carbohydrates in exchange for gathering things like phosphorus and nitrogen from the soil. Another really important way that plants do this is through something called the Rhizosphere – a little zone around the end of each root. At the end of a little tip, they pump a lot of sugar and carbohydrates straight out into the soil to feed the microorganisms and bacteria, which can be just as important as nutrients. The plant can’t necessarily feed itself in bare soil, but it can in relationship with a community of organisms.”

There are significant physical, chemical, and biological benefits of storing carbon for soil structure and our climate. Share on X

Deep, repetitive, and intensive tillage disrupts these networks and kills microorganisms below ground. Kyriakides notes, “In a forest where there hasn’t been any tillage, these networks are quite incredible.”

Many farmers understand the disruptive nature of tillage and are working to minimize this practice. The ultimate goal of reducing tillage is to build soil health and fertility. There are numerous strategies for building healthy soil and reduced tillage is just one of many components. Others include cover cropping, compost, diverse plantings, mulching, and more. Kyriakides says, “You can think of these practices as tools in a toolkit.” The main objective is diversity and resilience in the soil by fostering biological activity through these practices.

There are steps to building soil fertility when getting started and reducing tillage over the long term might require some initial tillage, depending on the land being worked. Kyriakides says, “I think we need to be doing some deep tillage just a couple of times, at Sandown, really strategically, so that is not going to be damaging things further. I think it’s necessary unless you want to wait decades for the biological processes to start to help that soil.” He adds that reducing tillage, “Is a destination, not an immediate goal for a lot of people.”

Building healthy soil is the best way to reduce emissions and build up climate resilience on a farm. When soil is tilled, carbon is released into the atmosphere, increasing emissions from agriculture and decreasing soil health for the farmer. Keeping carbon in the ground increases biological activity, water regulation, and storage of nutrients and cycling. There are significant physical, chemical, and biological benefits of storing carbon for soil structure and our climate.

Soil structure is especially crucial during periods of extreme weather. Kyriakides notes, “If [the soil] has a good structure throughout the year, it can take up water as it starts to rain and save like a bank account for the days when it’s needed.” In periods of heavy rain, the soil can absorb the water like a sponge and save this for the periods of drought we may experience.

 In contrast, “Any sort of climate disturbance that comes through is going to be amplified by poor quality soil,” says Kyriakides.

Michael Kosaka, head farmer and owner of Amazia Farm, decided to move into no-till for the sake of his soil and to reduce emissions on his farm. He says, “Every time you plow your field, you’re setting your microbes off and they are releasing all that carbon that they’re chewing through. So in that small way, we’re mitigating some climate change.” Kosaka has to till when starting a new bed for production. From there, he can reduce tillage in the following years and ultimately has achieved no-till on several areas of his farm. It takes patience and presents challenges at times, but Kosaka understands the importance of observing his land and implementing necessary interventions to achieve his goal of reducing tillage.

Financial considerations and farmer livelihoods are an important part of climate solutions in agriculture. Though we do need to reduce emissions coming from agricultural lands, farmers need to be able to make a living and continue to feed our communities. At The Sandown Centre, Kyriakides notes that they are farming in deeply compacted heavy clay and achieving the reduced tillage they are aiming for will take time and patience. He says, “We have farmers whose livelihoods depend on making a living this year, not ten years from now. So we need to be tilling in the short term to make sure that they can plant into the land and work with it.”

Cory Schurz from Root Renaissance Farm mimics a forest system on his vegetable farm through a variety of practices, including reduced tillage. Once beds are established, the soil is disturbed as little as possible. After every harvest, compost is added, roots are left to decompose, and the life in the soil is maintained within the beds. Schurz says, “Trees drop organic matter on the forest floor, and it builds and builds. When you go into a forest, you have this beautiful, rich, decomposed organic matter at the foot of the trees because nature doesn’t come in and rip everything out or grind everything up.”

Farming practices that contribute positively to a no-till system include cover cropping, mulching, natural additions such as compost and compost teas, diversified planting, and perennial planting. These applications, in conjunction with conservation tillage, are the best way to build healthy, living soil and reduce emissions in agriculture.

Tillage has become a vilified practice for its contributions to emissions. However, some tillage and intervention are necessary steps for farmers as they transition to reduced soil disturbance. Goals vary from farm to farm but reducing soil disturbance is the best way to trap carbon in the ground and build soil fertility. Soil disturbance may be necessary from time to time, but conservation tillage is possible on many farms around BC. This is crucial for reducing emissions in agriculture. Kyriakides says, “A lot of climate greenhouse gas emissions come from farming. I think farmers have a role to play and are at the forefront of this conversation because we are on the frontline of climate change. We are working with the land daily and seeing how it’s changing and shifting.” Conservation tillage plays an important and positive role in reducing emissions and contributing to the success of farms producing high-quality food.