Back to the roots for soil
Something is wrong with modern agriculture. Farmers should not have to be buying nitrogen and phosphorus to nourish crops. We are a carbon depleted nation. Farms should be run on fuel from today's sunlight and not with products from ancient sunlight.
Those are some of the fundamental beliefs that Ray Archuleta has accumulated during 30 years of experiences with the Natural Resources Conservation Service while stationed in Missouri, Oregon, New Mexico and North Carolina as an engineering technician for irrigation and a water quality specialist and while traveling across the country during his career.
On a recent 10-day tour, Archuleta spoke to farm audiences about practices designed to improve soil health and address the problems he was describing. One of his stops was at a grazing seminar sponsored by the NRCS, GrassWorks Inc., and the Glacierland Resource Conservation and Development Council with funding through the Great Lakes Restoration Initiative.
What Archuleta perceives as a major fault in agriculture today is its thrust at "mimicking nature" with such tools as tillage equipment, synthetic fertilizers, herbicides, and pesticides rather than working with nature itself to achieve the same goals.
Nature itself has provided at least 3.8 billion years of research data on that topic, Archuleta declared. "Work with nature. Don't try to control it."
Archuleta, who is popularly known within the NRCS as "the soils guy," believes that agricultural practices are based on the wrong foundation.
He particularly questions the widespread practice of tillage, describing it as very destructive because of how it interferes with the natural processes that promote soil health and how it even stimulates new weed growth.
Tillage breaks up the soil structure which creates the aggregate stability that allows water infiltration and accommodates water storage while also exposing the carbon in soil to oxygen, thereby resulting in the loss of the organic matter and carbon that are essential to soil health and plant nutrition, Archuleta pointed out. "Nature does not till the soil."
For far too long, research and education on soils have been much too heavily weighted to the chemical and physical properties of soil which giving scant attention to its biological properties and processes, Archuleta stated.
The principles of biology and ecology apply to all soil types and everywhere, Archuleta stressed. That's why he's both amused and bothered to hear that Wisconsin or any other state "is different" on how to address the question of soil health.
In trying to protect surface water quality, Archuleta believes there has been too much emphasis on buffers and terraces as the answers. He said that the effort needs to begin at the point where raindrops or wind gusts strike the soil, thereby leading to erosion.
One innovative practice which Archuleta endorses for growers of commodity crops is the rolling or crimping of a previous cover crop to stop its growth, followed by no-till planting of the new crop, resulting in a soil cover that thwarts weed growth; holds water and protects soil; leaves a cover ("instant armor") similar to the natural conditions in a forest or on a prairie; and provides the ingredients for organic matter and food for earthworms and soil microbes.
To illustrate his points, Archuleta demonstrated how differently and quickly chunks of soil dissolve in water depending on their organic matter content or whether they were taken from fields that are frequently or rarely tilled.
As the soil was placed in tubes of water at the program here, the sample with only .5 percent organic matter almost immediately dissolved and fell to the bottom, showing its inability to accommodate infiltration and how prone it is to erosion, Archuleta pointed out.
A soil sample with 6.5 percent organic matter remained firm for a long period and filled its pores with water.
Similarly, a difference in soil pores was noticeable in the dissolving rates and water infiltration for the tilled and no-till soil samples.
Regarding water infiltration, Archuleta cited examples of demonstrated cases showing per hour infiltration of up to 27 inches of water on open, nontilled range land compared to only 0.59 inch per hour on a harvested hayfield. Every one percentage point increase in soil organic matter boosts the soil's water storage capacity by 17,000 to 25,000 gallons per acre.
Soil health parameters
Soil pores or air pockets are created by the natural processes that involve microbes and protozoa, plant roots, organic matter and livestock manure and urine that work together to create soil aggregates which resemble cottage cheese, Archuleta explained.
Regarding carbon, Archuleta described it as "the armor" which reduces soil crusting after rainfall, limits extreme increases in soil temperature and provides the dark color which is a sign of good soil health. Because "hot soil changes the ecosystem," the soil should be covered at all times with some vegetation or plant debris.
Once their soil is thawed this spring, Archuleta challenges graziers and all farmers to take the shovel test for their soil health. Each shovelful should have the cottage cheese appearance in structure, have at least four earthworms and have evidence of rhizobia, while each cubic foot of soil should have 20 earthworms, he stated.
Observation on grazing
While complimenting graziers in general for already realizing many of those things and "thinking that way," Archuleta finds that a great percentage of them overgraze their livestock. Overgrazing is not good for the soil biology because, like the making of hay, it removes too much of the carbon; leaves the soil exposed to erosion and penetration of heat; and opens the way for growth of weed species.
But having animals on the soil is valuable because of how they interact with plants and the overall ecosystem, in particular by disturbing the soil surface somewhat and by providing manure, urine, and even saliva that is essential for feeding the soil microbes, Archuleta explained.
Traveling with Archuleta during the 10-day expedition around the Upper Midwest was Justin Morris, who is the new soil health specialist for the NRCS in Wisconsin and Minnesota.
A native of Washington, he has experiences with grass-based perennial agriculture, irrigation and pasture management on open range ranches and feedlots in Oregon, Utah, Idaho and Montana.
Compared to those states, "Wisconsin has an amazing opportunity" for both grass-based and other crop production because of the sufficiency and fairly good dependability of rainfall, Morris indicated.
He's also convinced about the role of animals as herbivores in creating healthy soil.
That's been true with the bison on the American plains, the animals in Africa's savannas and caribou on the tundra in Alaska, Morris stated. "Nature's ecosystem needs animals."
One factor which graziers and cattle managers can control is the livestock density and time period on any grazing paddocks, Morris observed. On that point, he opts for high concentrations of livestock for short periods in part because it mimics the habits of wild animals that gather tightly while they eat as a protection against predators.
Morris also lists reasons such as introducing a herd rather than individual mindset, inducing the animals to be less selective as they eat, and the even distribution of manure and urine. Another important criterion for him is to have the animals trample one third to one half of the available foliage to the soil surface for the multiple biological benefits that it will provide.
Too many graziers are expecting or forcing their animals to eat 80 to 90 percent of the available foliage, thereby creating bare soil and setting up undesirable consequences, Morris stated. But he also allows for flexibility within a grazing system, noting that the approach employed must be geared to what the goals are.
For the graziers who choose to move large groups of cattle frequently, Morris reviewed the terminology which is applied to the practice. He defines managed intensive grazing as having up to 50,000 pounds of live weight per acre, high stock density being up to 250,000 pounds of live weight per acre with two or three daily moves being necessary, and ultra high stocking density being more than 250,000 pounds of live weight per acre accompanied by at least three moves per day.
Morris promised that good biology could be restored to depleted soils with a proper approach to grazing and that old pastures can be revived with the planting of mixed species, and that beef cows will dig tillage radish out of the snow. Annual plantings of warm or cool season species should be dictated by the previous crop.
At least once during a growing season, Morris would allow plant species to express themselves by reaching their heading stage before being grazed. Based on one instance, he also reported how a grazing plan allowed a previously suppressed crop of Eastern gamagrass to establish itself as a major portion of a grazing paddock.
To a question about toxins in certain plants, Morris replied that all plants have some toxins, but unless there's a heavy concentration of plants with certain toxins, the diluting effect should prevent health problems in cattle. To answer those and other questions for themselves, he invited graziers to watch how their animals eat.