Yolo Olive Oil

In 1881 a yearling Mission tree from the nursery was planted on R. B. Blowers’ farm just south of Woodland. It began bearing in its fourth year and, in its last season before March 1891, yielded 25 gallons of olives. In Blowers’ opinion the Mission was “the most profitable olive that this soil has yet found.” Woodland merchants kept no pickled ripe olives in 1895 because there was no sale for them, and the many ripe olives pickled on the Blowers farm had to be sent away to find a sale. In 1905 his pure olive oil won a gold medal at the Portland exposition.

Morris & Smith, north of Woodland, put their first olive pulp under the press in 1899 and made about fifty or sixty gallons of oil. In 1900 the firm could buy only about seventy-five tons, and that December it was paying $40 a ton for Yolo and Solano olives. It dried, sacked and stored the ripe olives so pressing could run through the year, and ten men worked steadily through the drying and storing season. A ton of green olives made about thirty-five gallons of oil.

In 1909 the Winters Canning company built a separate olive packing and oil making department and put up 1,000 gallons of oil that season. In Woodland, V. Santoni, who had started a small plant two or three years before, expected about 1,000 gallons of oil from about seventy-five tons of olives bought from his neighbors. Many of the county’s heaviest growers, the Blowers estate among them, shipped their crops to the Ehman Olive Company at Oroville, where Freda Ehmann pickled ripe olives and by 1915 bought “all the available supply in the Sacramento Valley.” By November 1915 Santoni had won an exposition medal for his olive oil, but oil prices were “not satisfactory” after a boom in new plantings, the Sacramento Union reported.

John’s daughter Frances Wolfskill Wilson left part of the estate to UC Davis, and her will asked for the 1861 olive avenue to be kept “as a memorial to her parents and as a symbol of peace to the great State of California.” In 1946 Professor Hudson Hartmann and John Whisler grafted nearly 100 imported varieties onto many of the old Mission trees. UC Davis still grows olives at Wolfskill Ranch and harvests them in late October or early November.

In Davis, a row of olive trees on the campus side of Russell Boulevard dropped fruit on the bike path, where bicycle tires slipped in the oil “and sometimes the riders went flying.” In the early 2000s Sal Genito, director of the campus Grounds Division, asked Dan Flynn for a feasibility study rather than remove the trees. Flynn calculated the olive oil program could save the $60,000 a year the campus paid for cleanup and accidents. The first 1,200 bottles of UC Davis Olive Oil, filled by hand in a grounds office conference room, went on sale at Picnic Day in 2005. “Wham! They were gone on Picnic Day,” Flynn said.

UC Davis established its Olive Center in January 2008, with Flynn as executive director. In March 2010 its researchers bought bottles labeled extra virgin in Sacramento County, the Bay Area and Los Angeles County. Their July report found that 69 percent of the imported samples and 10 percent of the California samples failed the sensory standard for extra virgin oil, with flavors such as “rancid, fusty, and musty.” The study led to a federal investigation, and in 2014 the California Department of Food and Agriculture adopted olive oil rules that cited the UC Davis research.

Yolo County harvested 24,400 tons of olives for oil in 2024 from 8,076 acres, a crop worth $13,713,000.

1. 8,076Acres harvested
2. 24,400Tons
3. $13.7MValue of the crop

Frate Sole, Jim and Andrea Mayer’s orchard on County Road 27 near Woodland, takes its name from Brother Sun in the Canticle of St. Francis. Its trees are mostly Tuscan varieties, the same ones that dot the hillsides of Assisi. The fruit is hand-picked or raked from the trees into custom-built catchers and “cold-processed before the sun sets a second time.” Half the land is habitat, including a seasonal wetland the Mayers recreated, where about 100 greater white-fronted geese spent one winter. As of April 2025, Frate Sole had given oil for more than a decade for the Chrism that Bishop Soto consecrates for 200 parishes from the capital north to the Oregon border. It won another gold medal at the 2026 California State Fair.

At the same fair Sherri Wood’s Capay Valley Olive, from Capay Valley Lavender in Capay, won Best of Show among extra virgin olive oil blends with its French Blend in its first year entering, from its first harvest and milling. Wood said the award “celebrates the terroir of Capay Valley and the many hands behind this oil.”

The HIVE Tasting Room & Kitchen in Woodland prints “Frate Sole olive oil” on four dishes, among them the Tuscan focaccia. Séka Hills oil is on the rosemary focaccia with stracciatella at Paragary’s, the hand-pulled mozzarella with Ray Yeung’s heirloom tomatoes at Mulvaney’s B&L, and a mushroom salad and a margherita at Zinfandel Grille. The Midtown tasting room puts its Arbequina oil in olive oil ice cream.

In Colusa County, Organic Roots in Maxwell has made oil since 2013 and runs its own mill. Farther up the valley are Sutter Buttes Olive Oil in Yuba City and Calolea in Loma Rica.