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Home HortTechnology Conservation Tillage Systems Contribute to California's Flourishing Processing Tomato Industry
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Conservation Tillage Systems Contribute to California's Flourishing Tomato ProductionDAVIS, CA--A new report from a team of California extension and university researchers describes the development of the tomato processing industry in California's Central Valley as a "phenomenal success story". Over the past 90 years, the report says, California processing tomato yields (per acre) have increased over 740%, allowing California to claim a 95% share of the U.S. processing tomato production market.

The report in the American Society of Horticultural Science journal HortTechnology notes that, while the tomato production capacity of the California's Central Valley is related largely to the region's Mediterranean climate of rain-free summer growing seasons, sustained breeding and genetic improvement efforts coupled with advances in production technology have significantly contributed to the industry's increased productivity.

The research team's 12-year exploration resulted in a comprehensive summary of recent research and technological developments related to conservation tillage (CT) tomato production in California. "We started with advances in minimum tillage practices along with farmer innovations in strip-tillage tomato production and then described recent research findings on no-tillage tomato systems," explained the study's principle investigator Jeff Mitchell.

Traditionally, processing tomato production in California's Central Valley has relied heavily on tillage to produce high yields. However, recent research and farm innovation have produced a variety of conservation tillage management alternatives that cut costs, reduce soil disturbance, and produce fewer emissions. The term "conservation tillage" (as defined by the University of California Conservation Agriculture Systems Initiative) refers to management systems, such as no-till (NT) and striptill, "that reduce tillage intensity and soil disturbance to maintain 30% or more of the soil covered by residues from previous crops after seeding, or that reduce the overall number of tillage passes across a field by 40% or more relative to what was conventionally done in 2000."

The 12-year study at Five Points, California, demonstrated that CT methods reduced tractor passes by 40%, lowered tillage costs by almost $80 per acre (in 2011 dollars), and achieved yields comparable to standard tillage methods.

According to the report, there are several critical components of CT tomato production systems that will largely determine whether the approaches grow. Among the primary issues are the need to avoid contamination of mechanically harvested processing tomato loads by "trash" or soil surface residues, and the need to avoid unnecessary traffic in what will eventually be crop growth zones within a CT rotation field. The authors added that another possible constraint to sustained CT management in crop rotations with tomatoes is soil compaction. "No rigorous determinations of possible subsurface compacted zones arising from tractor and implement traffic have been conducted in any of the recent CT evaluations that have taken place in the San Joaquin Valley. To be sustainable over the long term, CT systems will likely need to employ some combination of very deliberate compaction avoidance with perhaps targeted zone or vertical tillage."

The report concluded that the cost savings and resource conservation benefits of conservation tillage tomato production systems warrant further evaluation, and projected that as comparable yield performance and net profitability are further demonstrated, a variety of CT systems will become increasingly attractive to producers and more common in the region's flourishing tomato growing industry.


The complete study and abstract are available on the ASHS HortTechnology electronic journal web site:

Founded in 1903, the American Society for Horticultural Science (ASHS) is the largest organization dedicated to advancing all facets of horticultural research, education, and application. More information at


Original Article:

Evolution of Conservation Tillage Systems for Processing Tomato in California's Central Valley
Jeffrey P. Mitchell, Karen M. Klonsky, Eugene M. Miyao, Brenna J. Aegerter, Anil Shrestha, Daniel S. Munk, Kurt Hembree, Nicholaus M. Madden, and Thomas A. Turini
HortTechnology 22:617–626. [Abstract][Full Text][PDF]

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