Posts Tagged: soil
Before digging in to spring planting, pay attention to building the soil, advises an article in the Los Angeles Times by Jeanette Marantos.
Marantos visited the Pasadena backyard garden of Yvonne Savio, the retired coordinator of the UC Master Gardener Program in Los Angeles County. Savio is the creator of the Gardening in LA blog, with new stories appearing "every other week or so."
“The old saying is, ‘Feed the soil, not the plant,'" Savio said. “When you just use chemical fertilizers, you're not establishing a long-lasting base of nutrition for the plant. It's just giving it a huge piece of cake on Sunday, and then by Thursday it's nutritionally starving.”
Savio recommends a steady diet of organic matter be spaded into soil, and a layer of organic mulch added to the top of soil.
When you continually add organic amendments to the soil, the dirt comes alive as the amendments decompose, creating the beneficial bacteria, fungi and the nutrients plants need to grow strong and healthy, Savio said. “It's really like a cafeteria where your plants can pick and choose what they really like.”
On the fifth anniversary of the United Nations' recognition of Dec. 5 as World Soils Day and just in time for the California Department of Food and Agriculture's awarding of $5.23 million in funding to promote the adoption of soil health conservation practices, the California's Healthy Soil Initiative celebrated its first ever California Healthy Soils Week.
For most, that might not sound like a holiday worthy of week-long festivities (a celebration style often reserved for birthdays), but to the passionate folks who've spent the last three years building the nation's leading climate-smart agricultural program, it marks the beginning of a new story of how California agriculture can contribute to feeding the world, saving water and cleaning our air, all while fighting climate change and buffering against its negative effects.
From Dec. 4 to 7, CDFA, in partnership with a broad swath of stakeholder groups ranging from state organizations to the private sector (Fibershed, including Community Alliance with Family Farmers, California Farm Bureau, CalCAN, CA Resource Conservation Districts, Roots of Change, and Fibershed, hosted a variety of panels, webinars, and tours to better demonstrate what soil health actually is, what it looks like, how to promote it, as well as barriers to adoption and on-farm challenges.
CDFA kicked off the week by unveiling a series of Healthy Soils Information Panels directly outside Governor Jerry Brown's office. The information panels included an Natural Resources Conservation Service-inspired infographic defining healthy soils as a dynamic interface of the four elements, containing approximately 45 percent minerals, 5 percent organics, 25 percent air, and 25 percent water and teeming with life on the order of 100 million to 1 billion individual bacteria per teaspoon. The next few banners featured the major benefits of healthy soils. Quite simply: More food. Less water-use. Cleaner air. Healthier planet. The last banner brings it all home with a case-study of all-star farmer, Jesse Sanchez, once honored in Washington, DC as a “Champion of Change.”
Dec. 5 – the official World Soils Day – was jam packed, starting with a 9 a.m. webcast on Climate Smart Agriculture, followed by a legislative staff briefing led by CDFA Deputy Secretary Jenny Lester Moffitt, and a reception to celebrate the connection between soil and food by indulging in the fruits of California agriculture. The briefing included two discussion panels -- one that featured scientists including UC Cooperative Extension advisors Daniel Munk and Glenn McGourty, East Stanislaus Regional Conservation District agent Jeff Borum and Margaret Smither-Kopperl of the USDA-NRCS Plant Materials Center, and one that featured pioneering farmers, Rory Crowley of Niclaus Nut Company, Michael Crowell of Bar-Vee Dairy, and Bruce Rominger of Rominger Brother's Farms. The growers discussed the benefits and challenges of no-till farming, or conservation agriculture, on their own farms.
The next day turned a bit more hands-on, with California EPA and CalRecycle helping deliver bags of compost, along with educational materials to legislative offices and with tours taking legislators out into the field -- first to the Recology compost facility, and then to Sierra Orchards where some of that compost ends up.
Capping it all off, Southern California got looped into the festivities with a tour of the Urban Farm in Los Angeles and keeping in the urban food systems theme, Sacramento Food Policy Group and ReSoil Sac hosted one last panel and reception at Hot Italian, a local restaurant that sources seasonally fresh, California-grown ingredients and is committed to improving communities and the environment. And it's not just talk, these guys walk the walk with a worm-bin on site to help process their waste into a valuable resource for local growers.
Throughout the week, the message was clear: the California Healthy Soils Initiative is here to stay. And while it might take an internationally recognized holiday or a statewide weekly celebration to remind us, soils are the foundation of life, of agriculture, and their health is inextricably linked to that of our own. As Rory Crowley of Niclaus Nut company reminded us, “Every day is World Soil Day on the farm.”
Powers of microbes: UC Davis graduate students get creative to teach farmers about soil microbiology
If you grew up in the 1980s or 1990s (or were a child at heart during that era), the famous Powers of Ten film likely left an indelible mark in your mind.
The film starts with a couple lounging on a picnic blanket and zooms out to the outer reaches of the universe, then back in to peer into the microscopic world of the human body: from white blood cells to DNA, and finally down to the proton of a carbon atom.
In its short 9-minute run time, Powers of Ten manages to inflame an existential angst about the size of a single human life while at the same time connecting the viewer to the beauty of the universe and the human body.
As a high school student watching the video, it filled me with the same sense of awe that I felt the first time I heard Carl Sagan's famous quote that “we are all made of star stuff.”
Powers of Ten reminds us that looking at the world from different perspectives, from the very tiny to the immensely large, helps create a better understanding of the natural world, our place within it, and how we can impact it for good.
Had Powers of Ten returned from outer space by zooming into a piece of soil rather than a the human body, it would have explored the billions of living creatures in one handful of soil, slowly scaling down from millipedes to earthworms to ants to nematodes to protozoa, and finally down to the soil's bacteria and fungi that make up the base of the soil food web.
The video might then have looked a lot like the recent workshop at the Russell Ranch Sustainable Agriculture Facility, which served as a science fair for farmers and researchers to learn about the minuscule but powerful soil microbe.
While farmers often have a baseline knowledge about soil microbiology and its importance on the farm, “the science is evolving so quickly at this point, that it can be hard to keep up,” said attendee Margaret Lloyd, UC Cooperative Extension advisor who works with small-scale farmers in Yolo and Sacramento counties.
The workshop coupled foundational principles of soil microbiology with practical on-farm management situations, making the case for farmers to actively consider soil bacteria, fungi, and other micro organisms in their decision-making process.
Jessica Chiartas, a fourth-year graduate student in soil microbiology and one of the workshop organizers, is somewhat of a soil science evangelist.
Her hope was to help workshop attendees better understand that “soils are not just physical, chemical systems. A majority of the processes that take place underfoot are biologically driven. Soils are living and breathing bodies and much like us, they need to be fed, covered, and protected from disturbance” in order to function in the long term.
The scale of microbial activity in soil makes it challenging to help farmers dig into just what scientists are talking about when they talk about microbes.
“It's important to talk about the scale of microbes,” Chiartas said. “So much of what goes on in soils is mediated by microbes and the scale that they operate on is far different than the scale we measure them at. Our typical method of soil sampling and analysis is analogous to harvesting whole fields of crops, chopping them up, throwing them in a heap and then trying to glean information about the individual plants.”
The presenters at the soil health workshop used vivid analogies to translate the abstract results of scientific research and hard-to-imagine scales into concrete, relatable concepts.
A single gram of soil may contain a billion bacteria, and several miles of fungal hyphae, the web-like growth of fungus. Translated into human scale, the numbers are mind boggling.
If a single microbe were a 6-foot-tall person, then a single millimeter of soil would be as tall as the empire state building. A typical soil bacterium contains as many DNA letters in its chromosome as two copies of “War and Peace.” A stack of copies of “War and Peace” equivalent to bacterial DNA from a single teaspoon of soil would be larger than the Great Pyramid of Giza.
A soil information revolution
The metaphors of scale are a fun thought experiment, and they could provide a jumping-off point for a discussion between farmers and scientists essential for improving our current understanding of soil as a living system. Climate change is expected to amplify the effects of soil erosion, compaction, nutrient leaching and other issues common in our current agricultural systems.
“We need improved management that works with the soil ecosystem to increase crop production while enhancing soil health,” said Radomir Schmidt, a postdoctoral researcher and workshop organizer. ”That's going to take a concerted effort and open dialog between farmers, scientists, and citizen scientists to discover, test, and implement these methods in the real world.”
We are now in the era of “soil information revolution," Schmidt said. As our knowledge of the soil microbiome expands, implementing this knowledge in agricultural practice is more and more possible.
This graduate student cohort is well-positioned to make the necessary connections, learning from farmers while helping them zoom in to see the essential lifeforms that impact their farm, then zoom out to help make decisions that are good for the farmer, good for the crop, and good for the microbe.
Farmers in the Davis area will have another opportunity to learn soil health fundamentals at a workshop this fall hosted by the UC Sustainable Agriculture Research and Education Program and Russell Ranch Sustainable Agriculture Facility. Details about the workshop will be posted here.
Healthy soil does much more than hold plants upright on the surface of the earth. It is a mix of mineral bits and old plant particles teeming with microbes to form a mysterious and complex web of life scientists are just beginning to understand.
While scientists use high technology to study heathy soil – painstakingly counting soil worms and bugs, sequencing the DNA of soil bacteria, for example – some farmers know intuitively whether the soil is healthy just by walking on it.
Scott Park is a first-generation Meridian, Calif., farmer. “When I step on a field and it feels like a road, something is wrong,” he said. “If it feels like a marshmallow or sponge, that's good.”
Park shared his farming experiences with 200 farmers, industry representatives, University of California Cooperative Extension scientists, Fresno State students, news media and others during a half-day UC workshop at the UC West Side Research and Extension Center in Five Points.
“The last 31 years I've been on a mission of building soil,” Park said. “I discovered it by accident and I've made lots of mistakes. But yields trend upwards every year on every crop. Being sensitive to building soil, I'm making a lot of money. And if I'm doing something for the earth, all the better.”
Park said he adds 10 to 15 tons per acre of biomass to his farm every year. He's using less fertilizer, up to 20 percent less water, and even experimenting on the farm by growing a commercial crop with just four inputs: cover crops, water, seed and sun.
“We got high-yielding, good-quality crops,” Park said. “Nobody was more shocked than I am that I got a good crop.”
Researchers are now using the scientific method to figure out the root causes of these empirical observations.
“There's a lot going on in soil,” said Radomir Schmidt, a UC Davis soil microbiologist who spoke at the soil health field day.
A teaspoon of soil has a billion bacteria and six miles of fungal hyphae, the filaments that branch out through the soil from fungi, Schmidt said. The microbes' interaction with living plant roots, the larger pores left by decomposing vegetation and tunneling worms and insects create a system that confers resilience to unforeseen challenges – such as pest pressure, torrential rainfall and plant diseases.
The field day was held under a tent pitched adjacent to an 18-year research trial at the 320-acre facility. The trial compares four farming systems side by side:
- Conventional system, with annual soil tillage and no cover crops.
- Conservation agriculture, with no tilling whatsoever and annual winter cover crops.
- No-till without the cover crop.
- Conventional tilling with a cover crop.
“Take a look over my shoulder to see the difference,” said Jeff Mitchell, UC Cooperative Extension specialist and the study leader. “We've found the cover crops and no-till reduce water needs, cut dust, and lower costs. And there may be more benefits than we realized.”
For example, a graduate student counted the worms, bugs, beetles and other microfauna in soil samples from each of the treatments. There were double the amount in the no-till, cover crop plots compared to the conventional farming system.
UC Cooperative Extension specialist Sloan Rice found that cover crops promote water retention in the soil after rainfall. There is very little water evaporation from the soil surface and water transportation from the cover crop plants in the winter, so little water is lost. Cover crops also promote more water infiltration below three feet.
Healthy soil management also shows promise in confronting global climate change by sequestering carbon in the soil, rather than depleting it.
Manager of Sano Farms in Firebaugh, Jesse Sanchez, was a speaker at the field day. He wasn't surprised by the overflow crowd.
“Farmers are more and more curious. They see some of us using cover crops, and they want to learn more,” Sanchez said. “There has been a swell of interest. I have a tremendous number of visitors every year.”
For more information about soil building, see the UC Conservation Agriculture Systems Innovation website at http://casi.ucanr.edu.
A consultant recently brought in some alfalfa plants to get another opinion on why growth was resuming slowly this spring. The field is located...