Posts Tagged: Soil
Soil acidity is an important factor for gardeners to consider when placing ornamental and edible plants in landscapes and vegetable gardens. It is possible to add amendments to the soil to adjust pH, but according to Dustin Blakey, UC Cooperative Extension advisor in Inyo and Mono counties, it's not always the best course of action.
“It is generally best to work with the soil you have, rather than try to attain the soil you wish for,” Blakey said.
Blakey wrote a six-page publication, “Adjusting Soil pH in California Gardens,” which is available for free download from the UC Agriculture and Natural Resources catalog.
In the new publication, Blakey describes how to quantify acidity, measure soil Ph, increase acidity and reduce acidity. Readers will also find typical desirable soil pH range for select garden plants, including fruit, nut and citrus trees, blueberries, avocados, azaleas, vegetables and lawns.
Download the full publication here: https://anrcatalog.ucanr.edu/Details.aspx?itemNo=8710.
Historically, chickens were not a rare sight on farms, where they contributed to soil fertility as they freely pecked and scratched around vegetable gardens and crop land. Now, UC Cooperative Extension specialists have launched a research project to quantify the potential for chickens to be part of safe and sustainable commercial organic vegetable production.
“It's not a new idea. A lot of farmers are trying this kind of thing,” said UC Davis International Agriculture and Development graduate student Faye Duan, the project coordinator. “But there is currently little scientific information for using chickens on a bigger scale, especially in terms of food safety concerns.”
The California trial is part of a national effort to diversify organic vegetable farms with chickens. Last year, the USDA-funded study was launched by Iowa State University horticulture professor Ajay Nair. The project also includes UC Cooperative Extension specialists Maurice Pitesky and Jeff Mitchell, based at UC Davis, and University of Kentucky entomology professor David Gonthier.
In the trials, chickens are introduced as part of a rotation that includes cover crops and a variety of vegetable crops. In California, chickens were placed on research plots in April following a winter cover crop of vetch, peas, fava beans and oat grass.
“We don't let the chickens run around the field,” Duan said. “We keep them inside of chicken tractors to protect them from predators.”
Twenty-nine birds live in each 50-square-foot tractor, essentially a floorless chicken coop on wheels. The tractors, built by UC Davis students Mallory Phillips and Trevor Krivens, are wood frames covered with mesh and plywood. Each day, the tractors are moved to a different part of the plot, where the birds can graze on cover crop residue and deposit manure. Adjusting to the daily move took time, Duan said.
“The first day, the chickens were confused. We had to go slowly. It's a learning process for the chickens and us,” she said. “But now, the chickens are excited to move to a new spot where they have fresh food to graze on.”
After 24 days on pasture, the chickens will be removed, and become part of the project's meat study.
“We have broiler chickens that are raised for meat,” Duan said. “Some people believe chickens that graze and eat grass taste better and are more nutritious. It will be part of the study to look at the chicken's meat quality.”
Once the chickens have done their part on the research plots, vegetables are planted amid the leftover cover crop residue and chicken manure. This summer, the experiment in California will grow processing tomatoes. Subsequently, melons, eggplant, spinach and broccoli will be part of the vegetable rotation in California or the other states involved in the project. Other replications of the trial will have the chickens immediately follow the vegetable harvest so they can graze on the crop leftovers before the cover crop is planted. Comparing the soil health, fertilizer needs, chicken quality and other factors will help the scientists optimize the rotation.
“Vegetable yield will be an important indicator of success,” Duan said.
Soil samples will be tested to determine the presence or absence of Salmonella bacteria after the chickens have been removed, said Pitesky, a poultry specialist and a project lead. Salmonella is a bacterium that can be part of poultry's microbiome. If the bacteria contaminates human food, it can cause illness.
“Since Salmonella lives in the chicken gastrointestinal system, when it gets into the soil, it will eventually be out-competed by bacteria more adapted to soil than the gut of a chicken,” Pitesky said. “There are many different types of Salmonella, and only a select few found in birds are the ones that are harmful to humans. Nevertheless, it is very important to test and use various practices to mitigate the presence of Salmonella on land that will be used for crop production following poultry.”
Early results of soil tests in Iowa and Kentucky detected Salmonella in the soil where chickens grazed, however, the bacteria disappeared very quickly.
With winter soon upon us, it's a good time to treat your garden bed just like the one where you tuck in at night, says Dustin Blakey, UC Cooperative Extension advisor, director and UC Master Gardener coordinator in Inyo and Mono counties.
Blakey hosted a webinar on Facebook during Healthy Soils Week 2020 (Nov. 30 – Dec. 5) to advise home gardeners how to promote healthy soils to maximize their gardening success.
“Some genius suggested we call garden plots ‘beds,'” he said. “It makes sense. Mom was right. Don't stand or walk on the bed. Keep it neat and tidy. And cover it, in the case of a garden bed, with organic mulch.”
The goal is to end up with garden soil that holds adequate water, nutrients and air, supports soil life forms, like worms, insects and microorganisms, and is convenient to work with.
“If I have to get a mallet to bang a trowel into the ground, it's not healthy soil,” Blakey said.
As a first step, designate permanent walkways in the garden so only those areas become compacted by foot traffic, leaving the plots where vegetables will be grown undisturbed.
“Along parts of the Oregon Trail, almost 200 years later you can still see the ruts where the wagon wheels rolled, and plants aren't growing there,” Blakey said.
He recommended gardeners cover their walkways with gravel, decomposed granite or organic materials like wood chips, bark or grass. Installing raised garden beds is an ideal way to differentiate growing and walking areas. In his own garden, Blakey built the beds four feet wide to have easy access to all the plants while standing on the walkways.
Add compost to the soil inside the beds to reap a variety of benefits.
“It's often said, no matter the problem, compost is the solution,” Blakey said.
Compost provides a food source for beneficial microorganisms in the soil. If soil is sandy, compost helps it hold water and nutrients. If the soil is clay-like, compost loosens the soil, making it more friable.
Covering the garden soil surface with mulch or cover crops is also critical to soil health, Blakey said. The topping moderates the soil temperature, supporting the organisms living below ground. The covering helps prevent weeds, and as the mulch breaks down, it adds organic matter to the soil.
“You can also grow cover crops,” Blakey said. “I'm surprised how few gardeners use cover crops. Put some seeds in the ground instead of buying a bag of amendments.”
Cover crops can be part of a healthy garden crop rotation, keeping roots growing in the soil all year long.
“Grasses scavenge nutrients. Legumes fix nitrogen. I grow sweet potatoes. They shade everything and keep the weeds at bay. A daikon radish cover crop penetrates deep into the ground, naturally tilling the soil,” he said.
Blakey discourages a common habit of some long-time gardeners, frequent rototilling with a heavy machine, and rather encourages what he calls “gentle tilling.”
“You don't need power equipment. Experiment with using a shovel,” he said. “My soil is loose and easy to work. Some beds, I don't even turn. I just plant directly in the healthy soil.”
View a recording of Blakey's one-hour webinar on healthy soil on the UC Master Gardener Program Facebook page: https://www.facebook.com/UCMasterGardeners. The UC Master Gardeners offer many online gardening resources and programs in most California counties. Find your local program at http://mg.ucanr.edu/FindUs.
After another record year for California wildfire, concern is now turning to the soil impacted by firestorms, reported Sarah Klearman in the Napa Valley Register.
High-temperature flames can incinerate vegetation and destroy plant root systems, said Toby O'Geen, UC Cooperative Extension soil specialist at UC Davis. The loss of vegetation destabilizes the landscape, making it vulnerable to serious erosion or flooding.
"The most important way to battle erosion is to have surface cover - living vegetation anchoring your soil," O'Geen said. "We have none of that. If you have soil with existing susceptibility (to erosion) and now nothing to hold it in place, it's a new disaster."
Particularly catastrophic fire can make the soil surface water repellent, which allows water to pond up and release higher concentrations of run-off water even when rainfall is low.
"That creates more massive erosive events - it gives rise to accelerated erosion, and in some extreme instances, mudslides," O'Geen said.
Consumers who purchase luxury cotton textiles want more than cool, soft, absorbent fabric. Increasingly, they demand clothing made from fiber grown using ecologically sound practices and they're willing to pay for it, said speakers representing the textile industry at a UC Cooperative Extension webinar on Healthy Soils for Healthy Profits.
A recording of the three-hour Sept. 17 webinar – which features clothing manufacturers, farmers and scientists – may be viewed on YouTube at https://youtu.be/rEm8pjbbnaE.
At the beginning of the webinar, UC Cooperative Extension conservation agriculture specialist Jeff Mitchell recalled the tragic 1991 dust storm on the west side of Fresno County, which reduced visibility on Interstate 5, causing a 104-vehicle pile-up that took 17 lives. The devastating accident foreshadowed debates about agriculture's role in reducing dust emissions, he said.
“It turns out that air quality was just the beginning,” Mitchell said. “There is now a whole cascade of expectations that buyers, consumers and the public are demanding of farmers about how food, fiber, feed and fuel crops are actually produced.”
Speakers from non-profit and commercial fashion and fiber organizations said they are anxious to get access to cotton grown using practices that promote soil health and sequester carbon to give their products climate-change mitigation cachet.
“What we envision when we look at the fields is groundcover year-round. Living roots in the soil year-round,” said Rebecca Burgess, director of Fibershed, a California non-profit organization that develops regional and regenerative fiber systems. “No-till or strip-till practices have garnered interest to protect soil from disruption, to avoid breaking up fungal networks. To produce cotton in a system that isn't eroding top soil.”
Wrangler jeans is a clothing brand that has successfully incorporated sustainably produced cotton into its products. The company worked with a group of Tennessee cotton farmers and the Soil Health Institute to produce 100% sustainable cotton jeans and sell them in its Wrangler Rooted Collection. Men's jeans in the collection run about $100 a pair. Ordinary cowboy cut Wrangler jeans range from $39 to $41 a pair.
Burgess said the fashion and textile industry is organizing itself to align with the 1.5-degree pathway, a target set by the Intergovernmental Panel on Climate Change that limits the rise in global average temperature to no more than 1.5 degrees C above pre-industrial levels.
“We want to work with farmers to enhance the ecosystem function of the landscape,” Burgess said. “We need to embed the cost of transitions into the cost of the cotton.”
Growing regenerative cotton in California comes with challenges that farmers are facing head on. Firebaugh farmer John Teixeira this year grew a multi-species cover crop that he terminated with a flail mower rather than a herbicide. He is making compost on the farm and in some parts of the farm spreading 8 to 10 tons per acre.
“We spread it on soil and also on cover crops to digest the cover crop,” Teixeria said. “We're adding bacteria. We would love to have more fungal diversity in the compost, but that's really hard. Fungi don't like to be disturbed. I believe microbes are the future. The key is to keep them alive.”
Gary Martin of Pikalok Farming in Firebaugh was using poultry manure on the farm, until it became prohibitively expensive. He then turned to cover crops and municipal compost to improve water infiltration, soil structure, water retention and increase organic matter. After three years, he added gypsum to improve the soil health.
He found that planting a cover crop without irrigation is a gamble.
“The net value of the cover crop is negative if it doesn't grow (because of a lack of rain),” Martin said. “Composting is more of a sure bet.”
Bowles Farm is experimenting with using a native plant cover crop.
“Native plants are designed to grow when we get moisture, and go away when we don't,” said Bowles Farm executive vice president Derek Azevedo. “It could be a habitat for pollinators.”
The company is also working on writing a carbon plan to map out how much carbon a cotton farm in Merced County can capture. The trial is managed with a multi-species cover crop, strip tillage, untreated seeds, fungal-dominated compost inoculation and a reduction in synthetic nitrogen.
“I can tell you already that the results of that carbon plan are being awaited by one of the brands in the San Luis Obispo area,” Burgess said. “They want to work with that cotton. They are excited to know what this can do for the climate.”
“We're interested in making products that stand the test of time, stay out of landfills, eliminating waste,” Daeschner said.
The company currently sources its high-end materials mainly from Italy, but is interested in transitioning to fabrics that are not only high quality, but also have a reduced environmental footprint. A new line, CO Natural World, focuses on the highest levels of sustainability, organic and regenerative materials, climate-beneficial wools, organic cotton, organic linen and recycled cashmere from garments that can no longer be salvaged.
“To create a garment that goes beyond the very least amount of harm to a garment that actually benefits the planet is the ultimate luxury,” Daeschner said.
The company is part of a network of five clothing brands that are working together to create the California Cotton and Climate Coalition, or C4 Coalition.
“We can do more together than we can do alone to boost the demand for beneficial cotton,” she said. “We are sharing pre-competitive information and pooling our financial resources to overcome existing gaps in the supply chain. And we will share our findings and results to attract new brands to the coalition.”
Calla Rose Ostrander, climate change communicator with the People, Food and Land Foundation, spoke from her home base in Colorado about opportunities for incentives to assist farmers in transitioning to healthy soils practices. She has been working with Maurice Marciano, the founder of Guess Jeans, and his daughter Olivia, who provided funding for part of the Bowles Farm project.
“They want to give back to the cotton community given the legacy of their company,” she said.
Ostrander said there is a network of philanthropic funders who may be interested in supporting the evolution of the cotton production system.
“There's a lot of commitment out there,” Ostrander said. “We're all trying to figure out how to do it and make sure that we can support the farmers in this transition. I'm really glad to see that the emphasis has stayed on supporting the producer and this idea has evolved. It takes time to build things.”