UC Delivers

UC studies overhead center-pivot irrigation in no-tillage systems

The Issue

Sustainable crop production in California’s San Joaquin Valley (SJV) relies on efficient management of increasingly scarce irrigation water and farm labor resources. SJV producers face powerful pressures for new, cheaper, and more efficient water-conserving cropping systems.

A potential means for achieving greater farm production efficiencies may result from the merging of two new technologies that are widely used in other parts of the world, but not yet in California. Coupling overhead low-pressure center pivot irrigation with no-till practices may be a “systems” means for achieving the kinds of production efficiencies that will be required in the SJV in the future.

The merging of these technologies is common in several regions of the world including the Pacific Northwest, throughout the Ogallala Aquifer region of the U.S. Great Plains, and in Brazil and Argentina, but neither technology is currently used much in California.

What Has ANR Done?

Since 1994, a group of researchers from UC Davis, Fresno County Cooperative Extension, and the UC Integrated Pest Management Program has been developing information on a variety of conservation tillage production alternatives including no-tillage planting systems. In 2005, this team began working with two pioneering farmers from Five Points, Calif. on a completely new crop production system for the region that merges overhead center-pivot irrigation with no-till crop rotations. By putting these technologies together, the need to perform intensive intercrop primary tillage is removed and considerable savings of time, labor, and fuel may in theory be achieved.

Studies on overhead, low-pressure center-pivot irrigated no-tillage systems have been instituted at UC’s West Side Research and Extension Center and in two farm fields in Five Points, Calif. to evaluate the economics and resource conservation potential that may be achieved from merging these technologies. To date, this work has demonstrated that yields can be maintained and labor can be significantly reduced with the center pivot system and that no-till planting in circles is possible in the rather thick surface residues that may accumulate as these techniques are sustained.

The Payoff

New crop production paradigms for the San Joaquin Valley

In this work, the University of California has contributed to the development, evaluation, and refinement of completely new crop production systems that may have tremendous value and application in future SJV cropping regions. In 2007, UC researchers with farmer and private sector partners demonstrated the ability to establish a variety of no-tillage crops in circles. Ongoing work is now underway to determine the water use efficiencies of center pivot no-till systems and to develop long-term crop and weed management strategies.

Contact

Supporting Unit: Department of Plant Sciences

Jeff Mitchell
mitchell@uckac.edu
Telephone (559) 646-6565
Mobile Telephone (559) 303-9689