A group of CASI partners has been working with Walnut Grove, CA tomato farmer, Michael Boparai, this summer on his efforts to produce processing tomatoes using an automated, precision-application center pivot irrigation system. Boparai is a new tomato farmer who recently purchased two 135-acre pivots that he had been using to irrigate alfalfa and corn before deciding to use them for his tomatoes in 2015.

The CASI team includes a diverse group of UC Cooperative Extension Advisors, Gene Miyao of Yolo, Sacramento, and Solano Counties, Brenna Aegerter and Michelle Leinfelder-Miles of San Joaquin County, and Cropping Systems Specialist, Jeff Mitchell of UC Davis, along with private sector partners, Dan Schueler of Senninger Irrigation Company, Rick Hanshew of Reinke Mfg., and Jerry Rossiter of CiscoAg. Several of these supporters of Boparai's goal of successfully producing tomatoes under his pivot this year have already met out in the field on a number of occasions to help him to assess progress of the crop and to develop water and crop management strategies for completing the 2015 season ahead of his harvest.

While overhead irrigation has been researched and used successfully for a number of crops that have been recently featured in several CASI peer-reviewed studies, the application of this proven irrigation technology to tomatoes in California has so far not fared well in the limited number of trails that have been conducted. A variety of reasons including the need to very carefully maintain an adequate watering regime throughout the season and to avoid falling behind in terms of recharging the soil profile so that tomato roots can adequately acquire stored moisture to meet the demand of evapotranspiration account for why overhead irrigation of tomatoes has faced problems in these past attempts. Knowing how much water is stored in the soil profile is also a key to managing irrigation of tomatoes and thus the team that is working with Boparai has recently installed soil water sensors and dataloggers in his pivot irrigation field so as to gain real-time information on soil water status that can then be used to schedule irrigations.

Because of the importance of tomatoes to many crop rotations throughout much of the Central Valley, being able to use pivot irrigation for this “anchor” crop is seen as being very important to the wider expansion of overhead irrigation systems in the region.

Additional updates and a summary of the learning that has taken place through this team effort with Boparai will be available in September.