From Tree to Table
BY LAUREN MCEWEN
Student efforts are at the heart of Cal Poly olive oil production
The buttery texture and grassy, fruity profile of Cal Poly’s new olive oil is generating intrigue in the local community as the ideal product for marinades, spreads, drizzling and more.
Students of the Plant Sciences Department produced their second batch of Arbequina extra virgin olive oil from the 230 olive trees at the Crops Unit in the fall — which is available for purchase on campus and in a number of retail stores across San Luis Obispo. The first batch, made from fruit harvested in 2023, flew off the shelves.
The delectable golden liquid is the final step in a process that has come full circle since the orchard was planted in 2020 as a senior project envisioned by Joni Shaffery (Agricultural and Environmental Plant Sciences, ’20).
Students and a contracted crew harvested the olives and Kiler Ridge Mill in Paso Robles pressed them into oil. Pomace, remnants from the milling, was then used by the Cal Poly compost program.
Students are involved in every facet of olive production, said plant sciences Professor Lauren Garner, providing numerous Learn by Doing orchard management opportunities that are unique to the crop. This includes pruning the trees to “ease the task of harvesting the olives by hand and balance the crop load to reduce alternate bearing,” Garner said. In doing so, the orchard will produce a more consistent crop each year. Other tasks done by students include pest management, irrigation and monitoring the fruit’s ripeness.
Pest management is a critical aspect of maintaining the orchard. Fourth-year plant sciences major Chrisann Perivoliotis explained that she was "involved in the biological control release of a small wasp that parasitizes the olive psyllid. It’s definitely the most unique, and one of the most memorable experiences I’ll take with me.” Students enrolled in the course, Biological Control for Pest Management, determined that the release, which was done in coordination with the California Department of Food and Agriculture resulted in parasitism of all of the orchard’s olive psyllids. Additionally, students in several classes participated in the deployment, monitoring and maintenance of traps that were part of the Integrated Pest Management program that helped control a key pest of olives, the olive fruit fly.
Perivoliotis works with the orchard crew to maintain the various orchards at the Crops Unit, doing everything from pruning, harvesting, fertilizer injections and irrigation management for all of the campus orchards, she said.
Perivoliotis even acquired professional experience from Kiler Ridge Mill, the same company that pressed Cal Poly’s olives into oil, through her connections with Cal Poly’s olive orchard. “I was able to work at the mill for a few weeks last season and it was a great experience,” she said. “The environment was really high paced, but it was awesome to be able to gain the knowledge of pressing olives and making oil firsthand.”
Cal Poly Olive Oil can be purchased at the downtown farmers market on Thursdays, the Cal Poly bookstore, Cal Poly Meats, Village Market on campus, at the Cal Poly U-Pick events on Saturdays, at the Poly Plant Shop, SLO Ranch Market and through Talley Farms’ Farm Box program.
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