Soil Health for the Common Good

California Healthy Soils Program Helping Farmers

By Jeff Mitchell, Ph.D., UC Cooperative Extension vegetable crops specialist and director of the Conservation Agriculture Systems Innovation center,

Though humans thrived here for millennia without planting seeds or herding animals, the phenomenal success of California’s short-lived agricultural experiment is staggering on a planetary scale, and represents barely over a century of building the highly productive food systems that benefit us all today. The farmers who manage the fields, orchards and vineyards of our Golden State contribute greatly to the common good by providing abundant food from an astonishing variety of crops.

Yet, present and looming challenges of water supply, climate change, air quality and the long-term fertility and sustainability of California’s agricultural soils threaten continued productivity. Such challenges compel farmers, researchers and the private sector to pursue creative soil management innovations that harmonize with the biological foundations of resource use efficiency if California agriculture’s future productivity is to be safeguarded.

Jeff Mitchell, Cropping Systems Specialist, UC Davis

This soil health initiative – which is based on principles including deliberate reduction of soil disturbance, generating and preserving surface residues from a broadened diversity of plant species that are grown to enhance active soil biology and capture maximum solar energy over time – is undoubtedly having a clear impact in many regions of the country. Within California, over the past four years, the Natural Resources Conservation Service has provided some $5.4 million in cost-share payments for soil health-related conservation practices to 172 applicants.

The California Department of Food and Agriculture’s Healthy Soils Program, launched in 2017, is designed to generate similar impacts and benefits. Indeed, CDFA has invested over $50 million to support 307 projects that incentivize adoption of these core soil health management practices. These two government programs are complementary, with NRCS incentivizing voluntary adoption and CDFA supporting a broader range of on-farm research and activities beyond simple practice implementation.

Observing our state’s annual cropland – the many bare, open fields we drive by when we’re out in the country – we see woefully few examples of the successful integration of these basic soil health principles across California’s immense farmscape. By and large, the very same tillage-intensive, high-disturbance soil management practices that have been employed for 90 years in most crop fields are still being used today.

When is the last time that you actually saw a no-till, high-residue field anywhere in California? Whenever we host out-of-state folks who’ve themselves pioneered soil health practice implementation back home, they are astonished by the outright sheer intensity of tillage disturbance and lack of protective residue cover in our state’s annual crop fields.

Government programs take a piecemeal approach. The full complement of integrated soil health principles are not being implemented in very many of either USDA’s or CDFA’s programs. Where cover crops are encouraged, they end up typically being plowed back into the soil by full-on disruptive tillage. That costs money and it flies in the face of the avowed comprehensive systems goals for soil health management that these agencies endorse. Piecemeal government incentives might contribute to very gradual forward movement of California’s food production systems, but they represent incremental “practice substitution” progress at best. These efforts lack a broader systems rationale for change.

A far more ambitious effort is now underway that goes well beyond these fragmented government initiatives. It involves a small group of organic farmers who themselves realize that core soil health, or conservation agriculture principles, can make not only ecological, but also economic sense.

These folks are looking far beyond cashing in on government rewards. They understand that evolution toward a natural systems agriculture has been their modern organic movement’s Holy Grail since its 20th century inception. On all fronts, this group realizes what Pennsylvania no-till and cover crop farmer Steve Groff points out, “You’ll become obsolete if you’re not future-proofing your farm ahead of not only environmental imperatives, but also market and consumer demands.”

This California farmer group might be leading a revolution, but as David Montgomery – author of Growing a revolution: Bringing Our Soil Back to Life – says, it is a movement that “is growing bottom-up, fueled by individual farmers rather than governments, universities or environmental advocacy groups.”

Their innovation – which involves year-round soil cover, greatly reduced disturbance tillage and integration of grazing animals into crop fields – aims to enhance the health of their soils, the health of their farms and the quality of the food they produce. Data compiled from project’s early stages demonstrate that sustained long-term “natural systems mimicry” these farmers have used over decades resulted in improvements in a number of key soil health properties, including carbon storage, water holding capacity and crop nutrient availability.

An underlying challenge that these farmers face, as does all of agriculture, was addressed by Guinda organic vegetable farmer and member of the project, Paul Muller:

“We are at a point where many people are asking how our farming systems can do more for the common good. Long-term stewardship and soil health is a common good; careful water stewardship enhances the common good; finding economic strategies to support and nurture those who grow our food and steward our resources for the long-term is a common good; capturing more carbon with cover crops and reduced tillage to feed a teeming microbial universe underfoot is a common good. Clothing naked soil, and minimizing dangerous pesticides in our food system is a common good; growing nutrient-dense food is a common good. It is all related, and companies can invest in an equitable supply chain where these common good values are properly rewarded. The question remains: ‘Who pays for the defense and enhancement of the common good?'”

This is not going to be an easy question to answer. Three members of the group recently met with representatives of 15 major U.S. restaurant chains to begin a dialog aimed at exploring what will be needed to reform our current food system in ways that promote soil, farm and human health, all while enabling farmers to continue to innovate and develop the alternative systems that we will all need. Project farmer Tom Willey may have surprised the listeners with his summation: “We find ourselves in the current predicament because we get what we pay for. Good food isn’t cheap, and cheap food isn’t good.”

2020-04-22T15:19:48-07:00April 24th, 2020|

Jeff Mitchell Will Show The Benefits of Soil Building Practices

Researcher Invites Public to Visit San Joaquin Valley Soil Health Demonstration site in Five Points

News Release

UC Cooperative Extension cropping systems specialist Jeff Mitchell is issuing a standing invitation to the public to visit the site of an ongoing conservation agriculture research project and see for themselves the results of long-term soil building practices.  

“Every Friday morning from 9 o’clock till noon, beginning in February and going through June, I invite folks to come to the project site to see up close and personal just what soil health means,” Mitchell said.

The research site is at the University of California’s West Side Research and Extension Center, 17353 W. Oakland Ave., in Five Points.

“I promise to be out there every Friday morning from Feb. 15 through June 26,” Mitchell said.

The project, funded by the Natural Resources Institute, compares plots that have been managed for more than 20 years in an annual rotation of cotton, processing tomatoes and, more recently, sorghum, garbanzo beans and melons under four different treatments: no-tilled plus cover crops, no-tilled with no cover crops, conventionally tilled with cover crops and conventionally tilled without cover crops.

“What we’ve got at this site is a very long-term example of exactly what implementation of a small set of soil care, or soil health, principles really means for soil function and management,” Mitchell explained.

Mitchell said that the study site in Five Points is a valuable resource for the people of California because of its dedicated adherence to principles that are widely touted to improve production efficiencies, reduce dust emissions, sequester carbon and reduce inputs over time.

“I recently heard about the value of publicly showcasing long-term sites such as the one we’ve got in Five Points. It’s being done in several other places, including the Dakotas and in Europe,” Mitchell said. “It just seems to make sense to open up our field more widely to folks who might be interested in seeing the remarkable changes we’ve seen and monitored for a long time.”

According to Mitchell, the NRI Project field is already “the most visited research field in the state,” but with this new invitation, he is hoping to have still broader impact.

“We’ve got a simply amazing resource here and I want folks to see it,” he said.

The study has been selected as one of the monitoring sites of the North American Project to Evaluate Soil Health Measurements that have been initiated by the Soil Health Institute of Morrisville, N.C. More than 20 peer-reviewed scientific articles have been published based on work done in this study field.

2021-05-12T11:05:06-07:00February 7th, 2019|

Jeff Mitchell: Conservation No-Till Is One Option For Water Conservation

Jeff Mitchell Has Devoted Career to Conservation No-Till

By Patrick Cavanaugh, Editor

Jeff Mitchell is a Cropping Systems Specialist at UC Davis, based at the Kearney Agricultural Research and Extension Center in Parlier. He has devoted 19 years to improving nitrogen and water use efficiencies in food, feed, fuel and fiber in no-till cropping systems.

Mitchell’s passion helped found Conservation Agriculture Systems Innovation Center (CASI) in 1998. CASI operates under the auspices of the University of California Division of Agriculture & Natural Resources.

His no-till research focuses on soil quality management and potential roles of cover crops and compost in intensive row crop production systems, and the use of cover crop mulches as a means of conserving soil water, suppressing weeds and increasing organic matter in no-till production systems.

He often cites a book called Plowman’s Folly by Edward H. Faulkner, published following the ruinous Dust Bowl. Faulkner dropped an agricultural bombshell when he blamed the then universally used moldboard plow for disastrous pillage of the soil.

This book is the 11th all-time cited, read, or acknowledged a piece of work related to the soil in the history of scientific literature.

“When it was written in 1943, it caused great arguments. The government got involved with the USDA trying to defend the science of the day,” Mitchell said.

The reason the book was so controversial is that it proved that there had been no scientific reason for plowing.

“He was getting in people’s faces by saying, ‘This might not be the way to do it,’ ” Mitchell said. “Faulkner’s stance was embroiling people.”

Mitchell’s work centers on conservation, no-till production of vegetable and cotton crops. The idea is to plant in the crops’ residue, which builds up a rather thick layer of mulch on the bed—leading to reduced water and nitrogen, as well as minimizing weeds.

Mitchell cited several growers in the Midwest and in California that are successfully practicing conservation no-till agriculture. And there is much more recent attention on soils with the Healthy Soils Program (HSP)—stemming from the California Healthy Soils Initiative, a collaboration of state agencies and departments to promote the development of healthy soils on California’s farmlands and ranch lands.

Jeff Mitchell describing the no-till soil that he has been working with for 19 years.

The HSP has two components: the HSP Incentives Program and the HSP Demonstration Projects. The HSP Incentives Program provides financial assistance for the implementation of conservation management that improves soil health, sequester carbon and reduce greenhouse gas (GHG) emissions. The HSP Demonstration Projects showcase California farmers’ and ranchers’ implementation of HSP practices.

“The principles that we are pursuing are allowing growers to keep excellent yields and maybe increase sometimes, cut out some inputs like fertilizers to save money, and to do it with less—less disturbance and fewer operations,” Mitchell explained. “None of this is new. It was 90 years ago when the Natural Resources Conservation Service established the principles of good soil management

  1. Healthy soil holds more water (by binding it to organic matter), and loses less water to runoff and evaporation.
  2.  Organic matter builds as tillage declines and plants and residue cover the soil. Organic matter holds 18 to 20 times its weight in water and recycles nutrients for plants to use.
  3. One percent of organic matter in the top six inches of soil would hold approximately 27,000 gallons of water per acre!
  4. Most farmers can increase their soil organic matter in three to 10 years if they are motivated about adopting conservation practices to achieve this goal.

“In 2013, a group of 30 farmers came up with a similar kind of a list,” Mitchell said. “They brainstormed on what would be good soil management, and they came up [with] feed the soil organic matter, reduced disturbance, increased diversity—the same as the NRCS list.”

Mitchell cited a newspaper article published in 1931. “People were finding benefits of cover crops in San Joaquin Valley farming systems. Now with the Healthy Soils Initiative, farmers are trying these techniques and evaluating it. There’s a lot of activity that is going on at many different sites in the state.”

Mitchell’s work at the West Side Research and Extension Center in Five Points on the conservation no-till approach has been with scientific protocol and replicated over 19 years.

“Initially, we would have several systems. In the no-till system, rotations of cotton, transplanted tomato, and a forage crops would grow back to back in a no-till system,” he explained. “Each crop would be planted in the residue of the previous crop. Over the years, the no-till plots have grey residue from last year plantings.”

A cover crop has been planted in a no-till field of cotton that followed tomatoes.

“Cover crops can also be part of the no-till system, which over the last 18 years have added 34 tons of biomass, which includes 13 tons of carbon per acre to the system, which is a good thing,” Mitchell said. “It adds fuel to the soil biology, but it’s not perfect.”

“My supposition would be that growing cover crops is more completed than people think. I have been at meetings where growers say: ‘are you kidding, I’m not going to grow cover crops because I do not have the water,’” Mitchell noted.

He said he understands the situation in not having enough water. But he explained, “In the winter time, yes there will be evaporation from the soil service every day. Radiation is beating down, and there will be evaporation.”

Evaporation in the cover crop field could be more nuanced. Maybe because the soil surface is shaded out, which would cool the soil, there may not be that much evaporation. The cover crops may increase infiltration of water in the ground, instead of it ponding on the soil surface.

“Yes, there will be some inevitable use of water by growing vegetation in the field in the winter, but it could be less than we think,” Mitchell said.

Mitchell then showed two large aluminum pans of soil. One showed soil dug up in an open field that has been tilled. The other container is soil with crop residue from the non-tilled plots.

He takes a handful of each and drops them into two individual gallon jars within an open metal grid with a few inches of water. This what Mitchell sees every time he does this. The large jar with tilled soil breaks up rapidly with soil particles dropping to the bottom. Within the no-tilled soil jar, the chunk of soil is very stable, with no soil particles breaking off.

“One thing that we are not doing now is looking at the potential benefits of these no-till systems and practices for conserving water and making better use of water that has been achieved in other areas of the world such as South America and the Great Plains and other regions of the United States. They do not have irrigation systems that California has; they have to wait for rainfall.”

“When we do the no-tilled system with lots of residue from back-to-back crops, with cover crops and with no disturbances, you may be able to keep 4 to 5 inches of water in the soil each year compared to a tilled crop.

More information on the Conservation No-Till system can be found here.

2021-05-12T11:05:07-07:00December 10th, 2018|
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