How to Regenerate Soil Using Cover Crops and Regenerative Land Management
December 14, 2014 | 129,217 views
By Dr. Mercola
High-quality soil is crucial to grow nutrient-dense plants. Tragically, most of our soil is being significantly damaged, thanks to modern farming methods. Gabe Brown is a true pioneer in teaching about regenerative land management, which helps restore soil health.Gabe was originally trained as a traditional farmer of the conventional mindset, using heavy tilling, genetically engineered (GE) crops, and chemical principles in his challenging growing farm environment of North Dakota.
I actually had the opportunity to personally met Gabe last week when I was keynote speaker at the ACRES USA conference in Columbus. He is every bit as knowledgeable and inspiring as his interview suggests. I had a chance to listen to his full day seminar and learned loads of great info..At this point, his operation is not certified organic, but he's implemented a number of land regenerative practices. He doesn't till his land anymore, does not use herbicides on crops that are growing. He's stopped using glyphosate altogether and has integrated cocktail cover crops and livestock rotational grazing.In 1991, he and his wife purchased the family farm from her parents, and they began farming conventionally using heavy tillage, low crop diversity, and season-long livestock grazing."Not being from a farm or ranch, I always tended to question why we do certain things," he says. "I had listened and attended a class that Alan Savory put on, talking about rotational grazing.I started doing some rotational grazing. I [also] had a friend in the northern part of North Dakota who was a no-tiller... In 1993, I went 100 percent no-till. Immediately, we started seeing some benefits... We were conserving moisture."
The Importance of No-Till for Soil Regeneration
This is a rather crucial point. Tilling is probably one of the most destructive aspects of modern-day industrial agriculture, as it disrupts and destroys soil biology."Tillage is the act of taking either a plow, a chisel plow, a field cultivator, or any type of steel or implement and destroying the soil's structure and turning the soil over.By reducing the tillage, we leave those soil aggregates, those pore spaces intact, which improve water infiltration and also provide home for soil biology," Gabe explains.Tilling is especially harmful for the mycorrhizal fungi—important soil fungi that attach to the roots of plants. Their thread-like filaments connect the plants together in an underground web that can stretch over long distances, forming a virtual "plant Internet," though which plant communication takes place.When Gabe quit tilling in 1993, he was the lone no-tiller in Burleigh County, North Dakota, where about 60 percent of the land is farmland. Today, about 70 percent of the farmland in this county is no-till. The fact that no-till has really caught on in the Northern Plains is very encouraging.Other important factors for soil health are crop diversification and cover cropping. Gabe learned the importance of this through a series of crop failures. Four years in a row, the farm lost most or all its crops to hail or drought. To keep his livestock fed, he grew various crop cover plants, and began noticing that his soil was slowly improving."We had four devastating years of crop failure in a row. I tell people that's the best thing that ever could have happened to me, because it taught me that I had to learn how to take care of the resource," he says.When he first started, soil tests on his land revealed organic matter levels of 1.7 to 1.9 percent. According to National Rivers and Streams Assessment (NRSA) scientists, organic matter levels in the area used to range around seven to eight percent some 200 years ago. So about 75 percent of the organic matter in the soil has been lost in just the last two centuries."One of the buzz words today is 'sustainable.' Everybody wants to be sustainable. My question is why in the world would we want to sustain a degraded resource? My operation today is still degraded. We need to be regenerative. We need to work on regenerating our soils, not just sustaining a degraded resource," Gabe says.
How No-Till Promotes Soil Health
Last summer, the organic matter on Gabe’s cropland ranged from 5.3 to 6.1 percent. So in just over 20 years of no-tilling and using regenerative land management principles, he’s been able to triple the amount of organic matter in the soil. Earthworms are another marker for soil health, and they too can be brought back when you abstain from tilling."There were no earthworms when we started. This past spring, my son did earthworm counts in our cropland. In a 12"x12"x2" slice of soil, we were averaging over 60. That's considerable when you start with zero. And that's just the earthworms. It doesn't count the myriad of other billions of soil organisms that are also in there," he notes."Earthworms, their castings and their secretions, are very nutrient-dense. When you grow a crop in a soil that's full of earthworms, those plants are going to follow the roots and are going to follow those channels that those earthworms make, and the nutrients will be supplied to the plant.The other thing it does that we don't often talk about is improve water infiltration. When we took over this operation, we could only infiltrate a half of an inch of rainfall per hour. In other words, if we had a rainfall event of an inch, over half of it was going to run off.When you're in a limited-moisture environment, you want all that rainfall to be captured and go into the soil. Well, in the last test we did, we can now infiltrate over eight inches of rainfall per hour, which is huge."Vermicompost—the compost produced by earthworms—is really one of the best compost you could get. Some sell it for about $1,000 for a cubic yard or about 1,000 pounds.The nice thing is that, once you have the kind of density of earthworms, Gabe describes, you're literally producing tens of tons of vermicompost per acre in your soil, and you don't even have to pay for it or move it. It's all done for free by the earthworms."As we move into these very diverse cropping systems and integrate cover crops into them, we actually plant cover crops to benefit soil life and to feed those earthworms. The cover crops become the compost that the earthworm cycle into usable plant nutrients," Gabe explains.
Improving Soil with Multispecies Cover Crop Cocktails
The cocktail of cover crops Gabe has incorporated into his land management system are a really important part of the equation. During those four years of hail and drought he grew mostly monoculture or two-species cover crops, such as triticale and hairy vetch, or sudan grass and cowpeas. Then, in 2006, after listening to Brazilian cover crop expert Dr. Ademir Calegari, he began using a multispecies combination."I was really upset with myself that I hadn't thought of it earlier. Because what I'm trying to do in my operation is mimic native range with the diversity of plant life and the diversity of wildlife, insects, etc. Well, that's what we're really doing with the cover crop cocktail, these multispecies mixes. Today, I plant up to 70 different species in a mix. What we're trying to do is mimic the diversity in nature.Think of it this way. If you plant a monoculture crop, that soil life is only being fed one root exudate. But if I plant a multispecies with 20 different species in it, that soil life is being fed the root exudates from 20 different plants. In other words, I'm accelerating biological time. We're able to regenerate soils much, much faster than scientists used to think were possible."
Five Tenets of Soil Regeneration
Using the following five tenets of soil regeneration, you may be able to add an inch of topsoil in a five-year period:
- No-tillage. This prevents soil erosion and also allows soil microbes to thrive
- Plant diversity and rotation
- Multispecies cover-cropping. While home gardeners can add crop cover like mulch or wood chips, large scale operations can achieve the same results by planting cover crops. Gabe grows cover crops on every acre of crop land each year. The cover crops may be grown before a cash crop, along with a cash crop, or after. But it's the cover crops that provide the carbon that becomes that all-important "armor" on the soil surface. Cover crops also act as insulation, so the soil doesn't get as hot or cold as it would if bare. This allows microbes to thrive longer. Also, the soil biology heats up the soil, which can extend your overall growing season in colder areas
- Maintaining living roots in the soil year-round. It’s important to have living plant roots in the soil as long as possible throughout the year. To accomplish this, use cover crops when not growing a cash crop.
- Livestock integration and diversification
Farm Program in Need of Serious Revisions to Integrate Soil Regeneration Practices
Unfortunately, one major hurdle that needs to be overcome before US farmers can more readily switch over to these regenerative principles is the government farm program, which subsidizes the growing of certain crops. At present, the farm program is strictly geared to monoculture production."I've come to the realization that we need to educate the consumers and the consumers need to drive the change through their purchasing dollars," Gabe says. "Let me tell you of this movement... My son and I started [a grass-fed beef] business in March, and we have zero advertising dollars. We've just been going to local farmers' markets. We already have over 650 repeat customers. We can't keep up with the demand right now. That goes to show you that if that's happening in a rural state such as North Dakota, what's happening in more urban areas?"...I tell the farmers and ranchers I talk to that carbon drives profitability of an operation. We have to start thinking of our farms and ranches as ecosystems and these ecosystems are driven by carbon. The more biomass you produce and the more diversity, the more carbon.Obviously, trees are a little bit scarce here in the Northern Plains. But for the average gardener, there's usually some type of tree removal service that has wood chips available in most communities that you can get and add to that garden. If you're adding carbon, you're going to increase the fungal component and you're going to increase the mycorrhizal fungi [that] secrete glomalin, which starts the formation of soil particles."...There's a great book by Dr. David Montgomery called Dirt: The Erosion of Civilizations. Dr. Montgomery talks about how all the civilizations such as the Incas and the Romans, their rise and fall occurred because of the degradation of their soil resource. I had the opportunity to visit one on one with Dr. Montgomery this past year. I asked him, 'How long do we have as a nation before this occurs to us?' And without blinking an eye, he said, 'Less than 50 years.' He said, 'We cannot continue on this path of degrading our resources like we have.'... [N]o-till is a piece; cover-cropping is a piece; diversity is a piece; and livestock integration is a piece. We have to bring all of these things together."
Feeding the World's Population Requires Emphasis on Soil Regeneration and Regenerative Land Management
Even if you're not a farmer, you can still have an impact by implementing the regenerative aspects of no-till, plant diversity, and using ground cover such as wood chips into your own home garden. Along with that, plant some pollinator species to provide a habitat for pollinators. Monarch butterflies, for example, need milkweed to feed and reproduce. When purchasing bee-friendly plants, make sure they have not been pretreated with pesticides that are toxic to bees, as this could actually do the bee population more harm than good... Most importantly, as a consumer, use your dollars to drive change, and educate others as to the importance of nutrient-dense food."We're spending more money on healthcare than any other country, but look what it's gotten us," Gabe notes. "The United States of America is now the 42nd healthiest country in the world. We're first in cancer, autoimmune diseases, attention-deficit disorder (ADD), attention-deficit hyperactivity disorder (ADHD), Parkinson's, Alzheimer's, and obesity. Why is that? We're degrading our resource so much that we no longer have the nutrient density in our foods in order for people to get healthy diets... We need to start thinking of food as health. Food is preventative medicine. The nutrient density of our foods has decreased anywhere from 15 to 65 percent for the last 40 years. That's uncalled for. It can't continue..."Indeed, the answer to "how will we feed nine billion people by 2050?" is: by regenerating our soils so that it can support more ample and more nutritious crop growth. In order to do that, we must change our farming model, because chemical-based monoculture is leading us straight toward the drop-off at the end of a cliff..."Look at our operation. We grow a diverse number of cash crops. We grow cover crops. We have beef, cattle, sheep, hogs, and chickens. I haven't even talked about how we allow beekeepers to come onto our land. There's a myriad of other potential income streams and enterprises that we can stack," Gabe says. "Feeding the world is absolutely no problem if we change the production model. For the small producers, it's simply a matter of stacking enterprises. Once you do that, you'll find that not only will you have more income streams to make your operation more viable, but you'll actually regenerate the soils much, much quicker."
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