Our five-step plan for healthier soils

By Gabe Brown

I want to start by telling everyone up front that I am not a soil scientist. I am a farmer/rancher who has spent the last 20 years working to improve the soil resource on my operation.

I have tried doing this in a myriad of ways, with some successes and many “learning experiences.” What I am going to do is share some of my experiences and observations, using my own operation to illustrate the concepts I follow. Realize that every operation is different. Each has its unique set of circumstances, and it is up to the operator to determine what works best on his or her own farm.

When my wife Shelly and I purchased our operation in 1991, the cropland had seen heavy tillage for many, many years. The crops grown were all small grains, primarily spring wheat, oats, barley and occasionally flax. Synthetic fertilizers and herbicides were used regularly. As a result, organic matter levels were at 1.7 to 1.9%, with water infiltration rates of only half-an-inch per hour. These were “normal” levels and rates for the area.

They were not, however, levels that allow the soil to function properly. As a comparison, native rangeland on our operation is around 7% organic matter with an infiltration rate of 6 inches per hour. My soil had become nothing more than a medium to hold a plant upright! I was farming a degraded resource, and I needed to accept that fact.

I believe this is one of the most difficult things for a producer to realize: We are all farming degraded resources. It is up to us to regenerate those resources.

What kind of progress can we make by focusing on regeneration? In July we tested those fields that originally tested below 2% organic matter and less than half an inch of infiltration. We found soil OM levels in the 5.3-6.1% range, with infiltration rates at  more than 8 inches per hour. We have achieved this without the use of synthetic fertilizers, pesticides and fungicides. Over the course of two decades we have made excellent progress in turning a degraded resource into healthy soils that are productive without requiring lots of expensive crutches.

How did we do this? Before starting the regeneration process, we must understand some basics of soil health.

First, soil is a living, breathing dynamic ecosystem. The organisms in this ecosystem are responsible for the clean air, clean water and healthy plants that lead to healthy animals and healthy people.

Second, if we expect those organisms to function properly, we need to provide them with what they need: a home and food. The home for the majority of these organisms is the pore spaces between soil particles. Many live in the small films of water that fill these pores. How do we ensure we have these pore spaces?

The first step was to eliminate tillage. Tillage destroys soil structure and reduces infiltration long term. I have been on hundreds of farms all over the U.S., Canada and Australia, and have never seen an operation using tillage that has the soil structure and infiltration of our long-term no-till fields.

Carbon is the food for nearly all of these organisms. That carbon is found in root exudates, organic material from plants, waste products from other organisms or the other organisms themselves. For me it has been a learning process to create the proper environment for supplying the carbon these organisms need. I have learned that you do not create that kind of environment through tillage.

After adopting zero-tillage, the second step to improving soil health is to increase diversity. I’ve made a point of observing the native prairie ecosystem, and then transferring what I’m seeing to my cropland. When looking at a native prairie ecosystem, one of the first things I notice is the incredible diversity. Grasses, forbs, legumes and shrubs all live and thrive in harmony. Think of what each of these species has to offer. Some have shallow roots, some deep, some fibrous, some tap. But all are releasing root exudates to attract soil biology.

Now think of the cropland acres being farmed today. Monocultures! How is the soil biology in those cropland acres going to proliferate and thrive when it is being fed a monoculture diet, and even then only during the time the particular crop is growing? Due to various factors, we now have a production model that shuns both diversity and the idea of planting more than one crop per growing season. Do you ever wonder why weeds grow when cropland is idle? Nature is trying to do two things: cover the soil, and provide a living root to produce the exudates that feed soil life.

There are four crop types: cool season grasses, cool season broadleaves, warm season grasses and warm season broadleaves. You should be able to find all four of these when looking at healthy native rangeland.

We need to see this kind of diversity on our cropland as well. This is why a corn/soybean rotation is unsustainable. Yes, you can grow those crops year after year, but not without significant inputs. On our operation we try to grow as many of the four crop types as we can each year on each field. Obviously we do not always accomplish this, but it is important to try. I will discuss this further in the next issue of Graze.

The third step in improving soil health is to feed soil life as long as you can throughout the year.  Here in central North Dakota, we typically get our last frost around mid-May and our first fall frost around mid-September. I used to think those 120 days were my growing season.

How wrong I was. We now fall seed biennials that grow into early winter and break dormancy earlier in the spring, thus feeding soil organisms at a time when the cropland used to lie idle.

I think of it this way: Just as I ensure that my livestock have adequate nutrition throughout the year so, too, do I need to do the same with soil life.

Step number four is to add cover crops to the rotation. By cover crops I mean multiple-species blends. In the ‘90s I grew two- and three-way blends such as sorghum-sudangrass, millet and cowpeas or hairy vetch, and winter triticale/sweetclover.

That all changed in 2006 when I heard a presentation by Dr. Ademir Calegari. Dr. Calegari is probably the world’s foremost authority on cover crops. He spoke of the importance in growing multiple-species blends, recommending at least six or seven species in a blend. I immediately thought of the diversity of native prairie. This just makes sense. Since then we have planted very diverse blends, usually with 15 or more species.

What this does is speed up biological time. Fifteen species do in one year what a single species needs 15 years to do. This strategy also provides a more varied diet for the biology within the soil. How healthy would we be if we were forced to eat the same thing day after day after day? How can we expect soil organisms to function properly if we restrict their diet?

The fifth step we have taken to improve soil health involves livestock integration.  By this I do not mean just turning some livestock out on crop residues, but rather utilizing livestock as a tool to improve the resource. Take a look at how prairie soils were formed.  Large herds of grazing animals moved across the landscape and did not return for an extended period of time, allowing the plants time to fully recover.

Not grazing livestock on our cropland is one of the most degrading things we can do for our resources. On our operation we grow multi-species blends, and then use livestock to convert these blends to a saleable product.

When we graze these blends we usually (but not always) use fairly high stock densities. We prefer densities of more than 500,000 lbs. of live weight per acre. I realize those numbers may scare some people, but remember I emphasized that everyone has to figure out what works best on his or her operation. We also only allow the livestock to graze approximately a third of the above-ground biomass. We want to leave two-thirds as armor to protect the soil and to feed soil life.

These are the basic steps we are using to regenerate our soil resource. My future articles will delve deeper into the intricacies of these steps. I will talk about cover crop blends and what we take into consideration in making decisions about what to plant, seeding rates, and other aspects of the program.

Gabe Brown grass finishes beef on his family’s ranch near Bismarck, ND.