Posts Tagged: Conservation Agriculture
Alan Wilcox of Wilcox Agri-Products and UC Cooperative Extension specialist Jeff Mitchell debated the challenges and opportunities for increased implementation of conservation tillage practices on California farms during the World Ag Expo in February, reported Alan Stenum in Farm Equipment magazine.
Wilcox said farmers are going to be resistant to anything they suspect will affect yield. Mitchell said creative innovation underway will have a big impact on some of the more challenging crops that are grown in California.
"This is a region where costs are high. The cost of doing business is high, and maximum yields on any crop are important to even break even," Wilcox said. "We're going to be intensely committed to water management and the maximum amount of water."
Mitchell said farmers in other parts of the U.S. started to switch to reduced disturbance no-till systems to conserve water.
"The recognition of the value of that opportunity to reduce soil water evaporation and have more water going through the crops through transpiration hasn't really sunk in here in California in large fashion," Mitchell said.
While Mitchell noted that water is essential to the discussion of conservation agriculture, there are other important aspects to consider.
"Biological cycling of nutrients in the soil, tightening up the system so there are fewer losses, either to the groundwater as some sort of pollution, or improving the overall soil function and nutrition provision capacity of the soil - that's not a small aspect of the overall system, nor are the opportunities for reducing costs," Mitchell said.
Wilcox said he would characterize the argument differently.
"The point is in all of our tillage strategies - and in every situation - we never compromise yield," he said.
Read the complete debate in Farm Equipment magazine.
More information about the use of conservation agriculture practices can be found on the UC Conservation Agriculture Systems Innovation website.
“Mike McRee has been extremely willing to share his experiences with others and has graciously hosted numerous public field days at his dairy farm over the years,” said Jeffrey Mitchell, UC Cooperative Extension cropping systems specialist and CASI founder.
The dairy producer, who milks about 2,000 cows at his farm west of Chowchilla, double crops his own dairy forage along with tomatoes and alfalfa crops on about 850 acres. After his pioneering efforts with strip-till – some of the very earliest in the entire San Joaquin Valley – McRee soon found that the conservation agriculture practice saved him time and money as he had anticipated, and yielded other important benefits for his farm as well.
McRee noticed improved water-holding capacity of his soil since working with strip-tillage, as well as increased consistency in the soil's ability to absorb water, mellower soil overall, and more consistent crop stands and yields overall.
Improved soil tilth, increased soil organic matter and earthworms give him consistent yields year to year without extreme highs or lows.
McRee's quest to improve the performance of his silage production systems began back in 2007.
He readily admits that he faced challenges early on.
He tried no-till wheat, but was limited in this effort by hard, compacted soils. Having the right equipment is a key to the whole endeavor, McRee points out.
He has worked with local NRCS partners and the EQIP program, which assists growers with implementation of practices to improve our soil, water and air resources.
Following a great deal of consultation with other growers and experimentation, he developed a very successful strip-tillage system for his silage corps. The change was spurred initially by his interest in reducing the number of times he had to drive a tractor through his fields to save fuel and labor.
He now does fall primary tillage using a Wilcox 7-shank subsoil ripper with a crumbler. Vertical tillage has replaced disc plowing to achieve a smooth seedbed without turning the soil over.
After winter forage is harvested, preparation for corn silage planting begins. McRee explains that he rips the soil down 13 to 14 inches and uses coulters to prepare the seedbed. After pre-irrigation, he uses the Dawn Pluribus strip-till row unit, a tool that preps an eight-inch band of soil for planting. Using GPS, he can run his tractor 6 to 7 mph for this pass.
“With three passes, I can do everything,” McRee said.
“Additionally, McRee has recently installed subsurface drip irrigation that utilizes dairy lagoon water for his silage crops,” said Priscilla Baker, NRCS soil conservationist in Madera. “This project is in partnership with the organization Sustainable Conservation.”
McRee received the award Oct. 13 at the annual meeting of the San Joaquin Valley Resource Conservation Districts held at the Wool Growers' Restaurant in Los Banos.
In 2005, the University of California, NRCS and the Conservation Agriculture Systems Innovation (CASI) Center established the Conservation Agriculture Farmer Innovator Award as a means for providing greater visibility to conservation agriculture pioneers in California. The criteria for this award are demonstrated innovation and leadership in the development, refinement and use of conservation agriculture systems within the California crop production environment.
For more information about conservation agriculture systems, visit http://casi.ucanr.edu.
How do you cut your water use by a third, cut your nitrogen use in half, maintain your tomato yield and improve your fruit quality?
“With patience, perseverance and by treating your soil like a living ecosystem — which it is,” says Jesse Sanchez.
Sanchez should know. He and Alan Sano have been experimenting with soil enhancements for 15 years on Sano Farms in Firebaugh. They believe they have hit upon a winning strategy — though their experiments continue.
Today, they grow 50-ton-per-acre tomatoes with half of the nitrogen (120 units) and a third less water than before. They also report fewer weeds and better tomato quality.
The soil organic matter (SOM) — the living portion of the soil that turns crop residue into minerals needed by growing plants — has gone from 0.5 percent to 3.0 percent, report Sano and Sanchez.
“The soil is like day and night,” says Sanchez. “You can dig it with your hands,” he says, cupping a handful to prove his point.
So how do you transition largely inert soil into the ecological powerhouse found on Sano Farms?
Cover crops, reduced equipment passes, and subsurface irrigation have been key, according to Jeff Mitchell, UC Cooperative Extension specialist based at the UC Kearney Agricultural Research and Extension Center. These practices combine to feed and protect the soil microorganisms often ignored in agricultural systems. Mitchell has been coaching the Sano/Sanchez team for over 10 years, witnessing their progress and connecting them with like-minded farmers and organizations.
“Farmers sometimes worry that cover crops will compete with the cash crop for water and nutrients,” says Mitchell. “We're starting to see at Sano Farms — looking long term — that the tradeoffs might actually be favorable.”
Sanchez says he terminates the cover crop before the tomatoes are planted, leaving the dead residue to smother weeds and feed the soil microorganisms.
The SOM also builds the sponge that allows the farm to thrive on less water, says Zahangir Kabir, soil health specialist with USDA's Natural Resources Conservation Service.
“A one percent increase in SOM builds your soil's ability to hold water by 19,000 to 25,000 gallons per acre. Calculating conservatively, Sano Farms' fields hold 50,000 gallons of water more per acre than they did before," Kabir said.
You can see this in action at Sano farms. “When it rains here the water soaks into the field. It stays put,” says Sanchez. “It doesn't run off like some farms.”
Sanchez, who received a White House Champions of Change Award last summer, says he knows farmers resist change. “But we can't stop change,” he says. “It's all around us.”
And, if they (farmers) do change the way they work with their soil, says Sanchez, “they are going to like what they see. ”
Sanchez will be a featured speaker at the second annual Latino Farmers Conference on Nov. 15 at the Monterey Hyatt Regency. The event is free but registration is required. http://www.nrcs.usda.gov/wps/portal/nrcs/events/ca/newsroom/events/?eventid=584#584 .
USDA NRCS produced a three-minute video profile of Alan Sano and Jesse Sanchez at Sano Farms in Firebaugh. View it here:
In California, 40 percent of agriculture is still irrigated by pouring water onto farmland, a much less efficient practice that drip and overhead irrigation. But those numbers are changing, reported Matt Weiser on Water Deeply.
Weiser interviewed UC Cooperative Extension cropping systems specialist Jeff Mitchell about the water-saving potential of using overhead irrigation, a system that is popular in other parts of the nation and world, but only used on 2 percent of California farmland. Mitchell was the primary author of a research article in the current issue of California Agriculture journal, which said that water and money can be saved using overhead irrigation in production of wheat, corn, cotton, onion and broccoli.
Mitchell said California researchers are looking more closely at overhead irrigation because they anticipate future constraints on agriculture, including water and labor shortages. Additionally, the system is ideal for combining with conservation agriculture systems, which include the use of cover crops, leaving crop residue on the soil surface and reducing tillage disturbance of the soil. The combination of overhead irrigation and conservation agriculture practices reduces water use, cuts back on dust emissions, increases yield and improves the soil.
Weisner asked how overhead irrigation could be as efficient as drip, when people typically see "water spraying everywhere from these roving sprinklers high off the ground."
Mitchell said farmers use pressure regulators and a variety of nozzles on hoses hanging down from the system to deliver water at precisely the rate and location where it is needed through the season.
"So, they're not spraying water. These are low to the ground, and there are various delivery nozzle practices that can be used," Mitchell said.
That is beginning to change.
UC Cooperative Extension and Fresno State agricultural production scientists researched overhead irrigation at the UC West Side Research and Extension Center for five years, growing wheat, corn, cotton, tomato, onion and broccoli and comparing them with crops produced under furrow and drip irrigation. With all of them except tomato, overhead irrigation led to similar or increased yields, according to the scientists' report published in the current issue of California Agriculture journal.
“Overall, we are very encouraged by these results, and they reflect the experiences that many California farmers have recently been having with overhead irrigation systems,” said lead author Jeff Mitchell, UC Cooperative Extension specialist. “We've confirmed that overhead irrigation systems work in California. We also concluded that there are opportunities to get even better results with more research and experience, particularly when overhead irrigation is coupled with practices that preserve crop residues and rely on reduced tillage.”
The tomato yields under overhead irrigation were disappointing, particularly since tomatoes have a prominent role in many Central Valley annual crop rotations.
“This isn't a simple process,” Mitchell said. “You can't just turn it on and let it go. It will require focused and dedicated farmer and researcher attention and innovation to solve.”
The authors are working with a team of Central Valley tomato farmers, processors, irrigation experts and research colleagues to improve overhead irrigation management in tomatoes. They are encouraged by the success of Walnut Grove farmer Michael Boparai, who achieved profitable processing tomato yields with overhead irrigation.
Overhead irrigation systems were invented more than 60 years ago. They now irrigate 50 percent of total U.S. farm irrigated acreage. In Nebraska, 87 percent of irrigated land is under overhead systems. By contrast, in California overhead systems irrigate only 150,000 acres, just 2 percent of the state's irrigated farmland.
Mitchell and his co-authors outlined several factors that contributed to its slow rate of adoption in California:
- Early adopters ran into serious problems, giving the systems an undeserved bad reputation that persists even though in recent years California farmers are using the systems successfully.
- Center pivot systems typically leave the corners of the field unirrigated, which can reduce production.
- Purchase and installation cost of the overhead system is substantially higher than furrow irrigation.
However, the UC and Fresno State research has shown many advantages.
- Overhead irrigation can be managed remotely and automatically.
- The system can accommodate different terrain and soil types.
- Overhead systems requires less maintenance than drip systems in terms of avoiding clogging of emitters and repairing leaks.
- Overhead irrigation may also help with salinity management by uniformly leaching salts from a crop's root zone.
- Precision irrigation, including overhead systems, are becoming ever more critical with coming groundwater regulations, surface water cuts and the increasing cost of water for farmers in California.
A significant advantage of overhead irrigation is its compatibility with other farm management technologies that optimize the farming system and reduce costly inputs, including water, fuel, labor and fertilizer.
“We're committed to continuing our work on the whole package – reduced tillage, preserving residue, improving water infiltration, improving soil water-holding capacity and increasing productivity uniformity – a system that we refer to as conservation agriculture,” Mitchell said. “We are working to encourage adoption of conservation agriculture in crops where viability of the system is well established, and facilitate the research and innovation needed to optimize conservation agriculture production in additional crops.”