As Allen Williams sees it, the world’s “oldest watering system” is the symbiotic relationship between plants and the soil, which mediates 90% of plant function.
“But we’ve disrupted that watering system through a lot of our modern agricultural practices,” says the founding partner and president of Livestock Management Consultants.
Williams says integrating livestock, cover crops and more flexible grazing programs can reverse this trend. On a farm in southern Illinois where Williams has worked with the owner to integrate cover crops, livestock rotations, biological products and other practices, they found earthworm middens surrounding the brace roots in nearly every field for 1,500 acres of corn — even in the heat of August.
“In 3 years, this farmer has reduced inorganic fertilizer inputs more than 55%, and it’s still going down,” he says.
“This system allows you to be more highly observant and pay attention to the cattle, the plants and the soil…”
— Allen Williams
Soil is Money
Having worked with farmers across North and South America, Williams says many fields and pastures have soils that are bacteria dominant and lack the earthworms, fungi, soil predators, nematodes and insects, such as dung beetles, that are crucial in nutrient cycling and organic matter creation.
There is a financial payoff for farmers or ranchers when they decide to take better care of their soils, Williams says.
In healthier soils, there is an abundance of mycorrhizal fungi that attach themselves to the roots of plants, and they’re 6-10 times better than the roots at picking up micronutrients from the soil and transferring them to the plant, he says. In turn, the plant roots produce food exudates to feed the fungi.
When left unabated, mycorrhizal fungi form a dense mat around the root zone and transfer nutrients from one plant to another. “In highly functioning fields, these mycorrhizal mats can actually cover thousands of acres,” he says.
Soil organic matter has a monetary value, Williams says, noting published research that concludes every percent of soil organic matter has $750 worth of nutrients in the soil. Building organic matter up to 5% could increase that figure to $3,700 in nutrients.
Soil health has a direct link to keeping more water on fields and pastures, but it doesn’t seem many farmers or ranchers are making the connection. Williams has found water infiltration rates of less than ½-inch per hour, even in fields in Iowa, Nebraska, Minnesota, Illinois and Indiana thought to have deep, dark soils.
Earlier this year, as Williams was working with farmers in the Mississippi Delta with better soils, he couldn’t find a single farm that had a water filtration rate greater than 1 inch per hour, and he found hardpans as shallow as 6 inches deep.
“If you build your water infiltration rates through building soil microbial population, through increasing and always having roots in the ground, and having cover on top of the ground, then not only do you get to keep the rainfall that falls on your farm or ranch, but you get to get your neighbors’ too,” he says.
Williams is a proponent of integrating livestock and cover crops in various ways to increase soil biological health and help growers keep more moisture and nutrients on their farm.
He typically spends his time early on measuring soil-water infiltration rates and gathering other baseline data so improvements can be tracked.
The grazing systems he advises look like this:
- Bale Grazing. This is a practice implemented through the winter months that involves setting out bales prior to winter in a checkerboard fashion, about 30 feet apart. Cattle traffic is controlled through a single strand of electrified poly wire.
Residue is left behind in the fields as the animals dismantle and feed on the bales. While many colleagues think that’s a waste of hay, Williams disagrees. “I’m doing a lot more than just feeding cows. I’m feeding my soil and I’m building soil,” he says.
Williams has tried this system in Michigan, Wisconsin, Minnesota, New York, Vermont, the Dakotas and Canada, and found bale grazing can add 0.5%- 0.75% more organic matter in a field in a single winter.
“It also makes it very, very easy to feed your cattle. We’re doing it through the winter instead of cranking up a tractor and hauling hay out to cattle,” he says. “We’re just simply moving a poly wire and letting the cattle eat the hay and harvest it themselves.”
- Winter Stockpile Grazing.Williams says this involves stockpiling everything from perennial forages to warm-season and cool-season plants for winter grazing.
While most farmers might think there isn’t much value with those stockpiled plants, Williams says past samples from those stockpiles showed 65% total digestible nutrients and relative forage quality of 179, indicating high-quality feed.
“And we’re not having to do anything except control their access to it through a single strand of poly wire,” he says. “That makes it a very simple way to be able to move the cattle through in a higher density matter through the winter months, as well as to apply that manure and urine in a very even distribution during that time period. Then it’s sitting there ready and prepped to fertilize that soil when the temperatures start warming up, the snow melts, the ground warms up and everything starts growing again.”
- Adaptive High-Stock Density Grazing.This is a system allowing for flexibility in grazing methodology based on weather and field conditions, rather than locking fields into a rigid system that never changes.
Williams says early support for this system grew due to research by Richard Teague at Texas A&M AgriLife Extension, who says short-term grazing on multiple paddocks can carry many more animals, have more forage than their neighbors and have excellent wildlife habitat.
They also achieve high levels of animal performance per acre while equaling the vegetation composition, soil cover, soil carbon, soil health and infiltration rates measured on ranches under light continuous grazing.
In contrast, Teague has said, ranches managed under higher stocking rates with continuous grazing had a higher degree of soil compaction, more bare ground, lower soil carbon, poorer grass composition, more weeds and lower forage production than those under multi-paddock management at high stocking rates, or the continuous grazing at low stocking rates.
On one farm in western Texas that Teague studied, cows were allowed to continuously graze for a long time on whatever part of the farm they chose, Williams says.
By tracking the GPS-collared cows, he found only 39% of the area of the ranch was even used by the cows throughout that year, as they congregated where the lush forage was typically growing. It took the farmer 21 acres per cow/calf unit to maintain them, William notes.
After that, the ranch was subdivided with temporary fencing, the rancher strategically placed water across the ranch and started grazing with higher stock densities, with a shorter grazing duration and longer rest periods. This helped the rancher reduce fencing costs and also cut the cow-calf unit from 21 acres to 9.
Leave Something Behind
One hallmark of adaptive grazing is the power of observation, and that comes into play in knowing how long to let animals feed and paying attention to weather cycles.
When grazing with soil health in mind, Williams says it’s crucial to think about not only what plant material is left above the ground, but what root mass remains below ground that will benefit soil microbial populations, plant recovery and forage biomass production.
“You can go up to 50% plant leaf removal with a single grazing and only have 2-4% root growth stoppage. But if you make another 10% jump, you remove an additional 10% of leaf material and you’re up to 50% root growth stoppage,” he says. “And if you get up in the 70-80% leaf removal area, then you get up to 100% root growth stoppage.”
Weather patterns also seem to be getting more fickle. Williams says many ranchers in his area of northeast Mississippi are getting into trouble in August and September and feeding supplemental hay because they haven’t accounted for changes in weather patterns in the last 10 years.
Williams says in his state, winter months tend to be very wet and the dry season takes over in early summer, with very little rain falling. When plants start losing roots below the ground, they shorten up, get stressed and don’t re-grow rapidly. Shrinking the root zone also affects microbial populations, he says.
“Every decision we make has a cascading effect,” Williams explains. “If we graze the crop down too tight, we stop root growth and have not only slowed down the time of plant recovery, but done a whole host of other things that are very negative to our operations.”
Another tenant of adaptive high-stock density grazing is using a multitude of different stocking densities throughout the year. Williams says it’s a mistake to ordain there will only be, for example, 200,000 pounds an acre in animals grazing year-round, and it’s better to adapt to the conditions and the rancher’s objectives.
To get to higher stock densities of 250,000, 500,000 or even 1 million pounds an acre, the livestock need to be moved more frequently. Some grazing experts he noted, such as Saskatchewan, Canada’s Neil Dennis, are moving them 12 or more times a day, and while most farmers can’t do that year-round, they could do it for a week to a field they’re targeting for rapid improvements.
“And then you can relax again and do just once-a-day moves. So there’s all different types of flexibility that you can build into the system,” he says.
Cows graze in a field at 150,000 stock density. Using higher stock densities, controlling access to fields, moving livestock more frequently and aiming for longer recovery periods can help no-tillers increase soil organic matter and water infiltration rates in their soils, and better meet the nutritional needs of their animals.
To illustrate how quickly adaptive grazing can change a field or pasture, Williams discussed a farm his business partner purchased 5 years ago in the Black Belt Prairie of Mississippi, because it was strategically located to another farm they were grazing. The land had been “absolutely used up” with bare, exposed soil dominated by weed or brush species.
Even though it was in the region with the second best soil in the state, that farm had soil organic matter levels of only 1.3%-1.6% across the farm, with water infiltration rates of less than half-inch per hour. The brix score on the forage species existing was less than 2, and major forage species numbered no more than 3-4.
After bale grazing the first winter due to a lack of available forage, adaptive grazing was implemented the following spring and summer, using higher stock densities, shorter grazing durations and longer rest periods.
“We didn’t put old, dry cows or yearling heifers on there. These were gestating, lactating cows that we depended on to make some money,” Williams says.
They calved in April and May and fed on ironweed, giant ragweed, sumac, pigweed and other plants that, much to Williams’ surprise, turned out to have favorable brix scores due to the plants being deep rooted.
With no tillage or chemical treatments in between, forage species were added to the program through tapping the latent seed bank, and they began to out-compete the weeds.
After 4 years, soil organic matter on that farm has improved to about 5.2%, forage species increased to 43, including natives, plant brix averaged 15-22%, water infiltration was at 8-10 inches per hour, and stocking rates decreased from one animal unit per 6 acres to 1 per 1.5 acres.
“Those 43 species were all the result of the latent seed bank, using the cattle to tap into the latent seed bank,” Williams says. “And on top of that, we’ve seen a significant increase in earthworm, soil-level insects, pollinators and wildlife. We’ve also been measuring an increase in soil microbial populations.”
Williams feels this system also has its advantages in terms of “trading labor for labor.
“If I wasn’t doing this, I’d have my butt seated on a tractor cutting, raking, baling hay and then feeding hay back in the wintertime. You’re not adding any time. And this allows you to be more highly observant and pay attention to the cattle, the plants and the soil.”
This farm purchased 5 years ago by grazing consultant Allen Williams’ business partner was reduced mostly to weeds and brush species in year 1 (left). But after implementing an adaptive high-stock density grazing program, soil organic matter improved from 1.3%-1.6% across the farm to an average of 5.2%, water infiltration increased from 0.50 inches per hour to 8-10 inches, and forage species increased from 3-4 the first year to 43 in year 4.
Increasing soil carbon is a key strategy toward building healthier no-till soils. To that end, Williams has been working with “Team Soil Carbon” — a consortium of soil scientists and experts — to examine how beef systems can help restore ecosystems and capture and store more carbon in the soil.
Last fall, they examined three operations — the farm Williams had just converted to adaptive grazing and two neighboring farms that had high- or low-level conventional grazing management for three or more decades. All had the same soil types.
At random locations on each farm, they dug 3-foot-deep soil pits and took soil samples at every 6-inch gradient for root growth and structure, soil biological activity, texture and aggregation, as well as total soil carbon.
They found Williams’ farm with adaptive grazing had, in the top 6 inches, 4.67% total soil carbon in horizon 1, compared to 1.64% for the high-level conventional farm — where animals were moved every 2 weeks — and 1.36% for the low-level farm where animals were allowed to roam at large on the ranch year round. The trend continued in the lower depths.
Soil organic matter for Williams’ farm was 4.26% in horizon 1, higher than the 3.28% for the high-level farm and 2.7% for the low-level farm. In addition, the researchers found Williams’ “carbon assessment per acre,” or carbon sequestration, was 188.13 tons per acre vs. 105 tons for the high-level farm and 81 tons for the low-level farm.
“That’s significantly higher carbon sequestration rates compared to the slow rotation and the continuous grazing,” Williams says. “That’s pretty staggering, when you see what that’s all about.”
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