California is the hub of some of the most strenuous environmental regulations in the nation. But when it comes to preserving groundwater resources, the state hasn’t been very progressive until the Sustainable Groundwater Management Act was enacted in 2014.
The SGMA limits water withdrawals to replenished levels in the state, where 80% of water use is related to irrigated agriculture from food-producing powerhouses like the San Joaquin Valley. High-residue no-till practices aren’t very common in California, where many of the crops produced are vegetables and no-till presents a built-in challenge.
But through the work of cropping systems specialist Jeff Mitchell and several other researchers at the University of California Cooperative Extension ag experiment station in Five Points, Calif., no-till has a brighter future.
Mitchell and a team of Agricultural and Natural Resources (ARS) researchers, farmer and private and public sector partners evaluated the potential for producing sorghum and garbanzos using high residue, no-till techniques in a four-year study. Using similar inputs and amounts and pest management, they showed that a garbanzo and sorghum rotation in no-till yielded at least as well as with standard tillage.
Sorghum yields were similar in no-till and standard tillage systems while garbanzo yields matched or exceeded no-till than in standard tillage, depending on the year.
In the trial, no-till garbanzos yielded an average of 3,417 pounds per acre vs. standard tillage with an average of 2,738 pounds per acre; garbanzo production in California, which is almost all in standard till, averages 2,300 pounds per acre.
The University notes reduced tillage and no-till has been under-utilized to improve water-use efficiency and there has been “very little research and there is very little information available to farmers on no-till production systems for the diverse array of crops that have been produced in the state historically.”
If water costs continue to rise and curtailments on water supply increase, the university envisions worries the value of agricultural land in California will eventually decline, but will provide “more of an economic incentive for using no-till for growing a portfolio of crops, such as sorghum and garbanzo, amenable to these pending constraints on irrigation.”
“There already exists high acreage of relatively low-value field crops in the state. As annual row crop farmers are faced with the need to reduce water use, knowing which field crops perform well in no-tillage conditions is important for the region,” the university says.
An outgrowth of this work on no-till systems is the group of about 15 farmers who are now a part of an NRCS Conservation Innovation Grant project that is looking at opportunities and approaches for reducing disturbance in organic vegetable production systems.
Hopefully the results of this work being done by the university and these farmers will spread throughout the agricultural sector in California so water resources will be available for future generations and food can be produced profitably and responsibly.