Farmers Measure Carbon for Healthy Soil
Farmers across a broad spectrum of the agriculture industry are embracing the ‘healthy soil’ movement. A key component of healthy soil is the amount of carbon it holds. But how can you tell? And how can you find out without disturbing the operations of a working farm or ranch? KBUT’s Christopher Biddle has more.
Bruce Allen is a third generation cattle rancher from Gunnison, Colorado. Through a co-op, he sells high end grass-fed beef to retailers like Whole Foods and Blue Apron. Like many in the industry, Allen is adapting to new understandings of what makes for healthy and productive pastures.
“In the spring, we feed hay on one of our sagebrush pastures that we purchased about 15 years ago, that had been grazed in a season long pattern, that had degraded the productivity and diversity in that pasture, and so we have been trying to introduce carbon to the pasture with hay off of our meadows.”
By feeding cattle in this once carbon poor pasture, the ranchers are able to put some back in. Whatever's left behind after feeding becomes part of the soil structure, as does the manure from the cattle. The idea is similar to subset of the healthy soil movement within agriculture that promotes “no-till” methods. Wilted cover crops rejuvenate, say a pasture usually meant for corn or wheat, as do the livestock that occasionally graze there. Popularity in such methods has exploded in recent years, even leading a small group of lobbyists to push for a new labeling system that identifies food produced with healthy soils. At the Allen ranch, the modified feeding practices have paid off, but the improvements are mostly anecdotal.
“There’s been a observable difference in the plant density and diversity, but I don’t have any data as far what is happening in the deep carbon profile, which is carbon that will stay in the ground even during drought years.”
Cue Jake Courkamp, a graduate student at Western State Colorado University in Gunnison, in the Masters of Environmental management or MEM program.
“I kind of came into this program with a n idea of an area that I wanted to focus but I was knew from the beginning that I wanted to address a community need, so the frist thing I did when I got here is just you know, ask my advisor, what question can I help answer, what can I work to actually that somebody in the community actually needs or wants to address.”
Western’s MEM program is designed to foster a better connection between the school and the surrounding community, which includes large swaths of ranchland. Bruce Allen says that makes working with students and researchers from the school more appealing
“I’m definitely interested in gaining a better understanding of how our management practices are influencing the organic matter on our rangelands.
And that’s why he needs to be able to track that deep carbon profile of his pastures.
“As climate change impacts us with more variability and drought , it’s pretty critical from just a business perspective, not even a social good perspective, that we build more resiliency within the eco-systems that we manage and to be able to build up organic matter so the water cycle is more stable through draughts, and there’s better overall health.”
“For every unit of carbon in the soil, it can hold eight units of water.”
Again Jake Courkamp.
“So if you double the amount of carbon in your soil, you’ve increased your water holding capacity by eight times.”
His goal was to establish a repeatable method for measuring the amount of carbon in the soil, as well as baseline for comparison. He took more than 12 hundred core samples, a little under one sample per acre of the plot of land he studied. He heated them up, combusting any non-organic material. He was then able to calculate the amount of carbon based on the weight of what remained
It’s been more than a year since courkamp began this work. Since then the healthy soils movement has spread. It was featured in a story by NPR in April as being embraced by major names in the industry, like Monsanto and General Mills. NPR said that It’s the same message from groups like the Union of Concerned Scientists and the Nature Conservancy.
Jake says he’s seen interest in his study from cattle businesses that were most impressed with how the method was developed in the context of a working business. That’s actually encouraged him to try to publish his results.
“I think the main thing to understand here is that trapping carbon underground, taking it out of the atmosphere and trapping it underground, is actually a bi-product of actually making the system more productive. Climate change abatement is kind of a co-benefit of just having a more productive system.”
“Rather than seeing cattle as an issue, I would posit that under certain management techniques we can actually use grazing for a tool to improve abating climate change, and the primary driver in that is getting carbon sequestered into the soil.”
For KBUT, I’m Christopher Biddle.