Posts Tagged: overhead irrigation
Overhead irrigation holds water-saving potential for California farms
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.
Enhanced irrigation and crop management technologies developed in Five Points, Calif.
The need to produce more food, feed, fiber, and fuel with less water now looms as perhaps the greatest challenge ever faced by farmers worldwide. Our ability to meet this challenge may well determine not only our overall quality of life, but also our very survival in the future. Developing and adopting enhanced irrigation and crop management technologies that achieve greater water-use efficiencies is essential.
What Has ANR Done?
For the past several years, a team of researchers, farmers, and private sector partners has been working at the University of California West Side Research and Extension Center in Five Points, Calif. to develop enhanced water and crop management systems for a range of crops commonly produced in the central San Joaquin Valley. This work has focused on the coupling of advanced sustainability technologies (such as precision overhead and subsurface drip irrigation systems) with strip-till and no-till planting to achieve cheaper and more sustainable systems.
The use of overhead irrigation (sometimes called "mechanized" irrigation) is not new in many parts of the world. Overhead pivot irrigation is widely used in the Pacific Northwest, the Great Plains, and the southeast U.S. as well as in many other places around the world. It is the most widely used irrigation system in the U.S. and has been successfully adopted in those regions for decades, but it is not widely used in California.
The Five Points research team is working to couple the proven benefits of overhead irrigation, including labor, cost and water savings, with additional benefits derived from preserving high amounts of surface crop residues. "Our goal," says UC Davis researcher Jeff Mitchell, "is to follow in the steps of legendary South Dakota State University researcher Dwayne Beck, and the no-till farmers he works with, to have crops use water more efficiently."
The Payoff
Coupling precision overhead irrigation with no-tillage increases efficiencies
Working with colleagues at Valley Irrigation in Omaha, Neb., the California team found that irrigation water application uniformity for the overhead system is 93 percent. This excellent level of application uniformity allows for less water use to meet irrigation demand than systems that are less uniform, such as surface or gravity flow furrow irrigation. In addition, the team showed that 13 percent (4 inches) of soil water evaporation can be saved in the soil during a typical summer season when a thick matte of residues is on the soil surface. This research shows the potential for California farmers to reduce water use and evaporation by combining overhead irrigation and no-till practices.
Contact
Supporting Unit:
Department of Plant Sciences, UC Davis, Department of Land, Air and Water Resources, Fresno County Cooperative Extension
1. Jeff Mitchell, Department of Plant Sciences, UC Davis
2. Wes Wallender, Department of Land, Air and Water Resources, UC Davis
3. Will Horwath, Department of Land, Air and Water Resources, UC Davis
4. Dan Munk, Fresno County Cooperative Extension
Merging conservation tillage with overhead irrigation systems
"One of the things that we see with overhead systems and the sprinkler packages that we have attached to them is that they are highly efficient," said Dan Munk, UC Cooperative Extension advisor in Fresno County, on the video. "They are highly efficient systems because they apply water uniformly. If we time this properly with proper irrigation scheduling techniques, we can reduce the amount of water applied."
Water, notes Monte Bottens, president of California Ag Solutions, is "the key to everything."
"If the water is not there and the water is not right, forget it," Bottens said.
West side farmer John Diener goes on to explain in the video that, in addition to delivering water uniformly, overhead irrigation, such as center pivots, gives farmers more flexibility with the land.
"All the tillage we did prior to having pivots was done primarily so we could run water from one end of the field to the other and put it on uniformly," Diener said. "With this practice, we have eliminated the need to have such great uniformity on the soil surface and, as such, we can do more non-tillage practices that allow us to store more carbon in the soil."
The University of California dedicates its first center pivot irrigation system at the UC West Side Research and Extension Center on Thursday. The dedication is part of the annual Twilight Conservation Agriculture field day, scheduled for 4 p.m. Sept. 13. Farmers and other members of the public are invited to the free event to see the system in operation and learn how overhead irrigation can be combined with no-till or minimum-till farming methods to create a more sustainable, profitable and environmentally sound agriculture industry. The field day includes a free barbecue dinner. For more information, see the field day announcement. To register, go to http://ucanr.edu/TwilightRegistration.
The body of CT research knowledge continues to grow
UC scientists presented recent additions to the growing body of research on conservation tillage in California at the second annual Twilight Conservation Tillage and Cropping Systems field day last month, demonstrating progress in agricultural systems that will help farmers cut production costs, reduce soil disturbance and save water.
UC scientists and their partner farmers are conducting research that addresses the current needs of the San Joaquin Valley agricultural industry and research that is looking to the future by anticipating changes that may need to be negotiated in coming decades.
During the field day at UC's West Side Research and Extension Center in Five Points, Calif., participants visited two primary research areas. The first is the longest-standing conservation ag system study in California, where a cotton/tomato rotation has been farmed for 12 years running. The plots include standard tillage with and without cover crops and conservation tillage with and without cover crops.
“This might be the most-visited research field in California,” said Jeff Mitchell, UC Cooperative Extension vegetable crops specialist and chair of the CT workgroup. “Many students and scientists have conducted research here.”
For example, scientists have been able to quantify significant improvements in soil quality with the use of cover crops and conservation tillage. UC Davis soil biochemist Will Horwath reported that conservation tillage combined with an off-season cover crop has increased the soil carbon content close to five tons per hectare.
“Is that significant?” Horwath asks. “Yes. In 10 years, we have almost doubled the soil carbon content.”
Because of the valley’s dry, hot climate, the native soils are typically very low in carbon, which is a characteristic of low soil quality. Carbon in the soil acts as a glue, helping reduce wind erosion.
At the second research field, conservation tillage research is being combined with overhead and subsurface drip irrigation. Coupling overhead irrigation with conservation tillage is common in other regions of the U.S., but is just beginning to get attention in California.
“There are more than 17,000 center pivots in the state of Nebraska, and it is estimated that there are somewhere between 300 and 500 pivots currently in use in California, the No. 1 ag state in the nation,” Mitchell said. “This situation is changing rapidly.”
Overhead irrigation is efficient, automated, allows for diverse cropping and, with soil residues from conservation tillage, permits uniform infiltration.
Four users of overhead irrigation shared their experiences with the irrigation system at the field day. West side farmer John Deiner said mechanized irrigation has significantly reduced labor input in his agronomic crops while boosting crop yields.
“Our corn grew two to three feet taller under the pivot,” he said.
Will Taylor of King City grows potatoes for In and Out Burger under center pivots. He said his yields are 20 percent higher when using the overhead irrigation system.
“Once you overcome challenges,” Taylor said, “they’re awesome.”
He demonstrated their ease of use by bringing along his 9-year-old son Liam, whom he said can already manage the machine.
Darryl Cordova of Denair uses overhead irrigation in a hilly area on the east side of the valley.
“What used to take three guys six hours of moving pipe is now done with a push of a button on my cell phone,” Cordova said.
Scott Schmidt, who farms across the street from the West Side Research and Extension Center, said he has learned how to successfully use overhead irrigation and conservation tillage from the “school of hard knocks.”
“Most of the problems have been self-inflicted wounds,” Schmidt said. But now, he calls the system “flawless.” “We have seven pivots that I operate remotely from my phone.”
The body of CT research knowledge continues to grow
UC scientists presented recent additions to the growing body of research on conservation tillage in California at the second annual Twilight Conservation Tillage and Cropping Systems field day Sept. 8, demonstrating progress in agricultural systems that will help farmers cut production costs, reduce soil disturbance and save water.
UC scientists and their partner farmers are conducting research that address the current needs of the San Joaquin Valley agricultural industry and research that is looking to the future by anticipating changes that may need to be negotiated in coming decades.
During the field day at UC's West Side Research and Extension Center in Five Points, Calif., participants visited two primary research areas. The first is the longest-standing conservation ag system study in California, where a cotton/tomato rotation has been farmed for 12 years running. The plots include standard tillage with and without cover crops and conservation tillage with and without cover crops.
“This might be the most-visited research field in California,” said Jeff Mitchell, UC Cooperative Extension vegetable crops specialist and chair of the CT workgroup. “Many students and scientists have conducted research here.”
For example, scientists have been able to quantify significant improvements in soil quality with the use of cover crops and conservation tillage. UC Davis soil biochemist Will Horwath reported that conservation tillage combined with an off-season cover crop has increased the soil carbon content close to five tons per hectare.
“Is that significant?” Horwath asks. “Yes. In 10 years, we have almost doubled the soil carbon content.”
Because of the valley’s dry, hot climate, the native soils are typically very low in carbon, which is a characteristic of low soil quality. Carbon in the soil acts as a glue, helping reduce wind erosion.
“There are more than 17,000 center pivots in the state of Nebraska, and it is estimated that there are somewhere between 300 and 500 pivots currently in use in California, the No. 1 ag state in the nation,” Mitchell said. “This situation is changing rapidly.”
Overhead irrigation is efficient, automated, allows for diverse cropping and, with soil residues from conservation tillage, permits uniform infiltration.
Four users of overhead irrigation shared their experiences with overhead irrigation at the field day. West side farmer John Deiner said mechanized irrigation has significantly reduced labor input in his agronomic crops while boosting crop yields.
“Our corn grew two to three feet taller under the pivot,” he said.
Will Taylor of King City grows potatoes for In and Out Burger under center pivots. He said his yields are 20 percent higher when using the overhead irrigation system.
“Once you overcome challenges,” Taylor said, “they’re awesome.”
He demonstrated their ease of use by bringing along his 9-year-old son Liam, whom he said can already manage the machine.
Darryl Cordova of Denair uses overhead irrigation in a hilly area on the east side of the valley.
“What used to take three guys six hours of moving pipe is now done with a push of a button on my cell phone,” Cordova said.
Scott Schmidt, who farms across the street from the West Side Research and Extension Center, said he has learned how to successfully use overhead irrigation and conservation tillage from the “school of hard knocks.”
“Most of the problems have been self-inflicted wounds,” Schmidt said. But now, he calls the system “flawless.” “We have seven pivots that I operate remotely from my phone.”