Off The Beaten Path: The Wolfskill Olive Ranch

Near Winters in California’s Yolo County stand rows of Mission olive trees planted more than a century and a half ago. Neglected for decades, then rescued as a living laboratory, they tell the whole story of how American olive oil grew up.

The Wolfskill Ranch sits in the flat, hot farmland near Winters, west of Sacramento. In the nineteenth century a settler named John Wolfskill developed it from a Spanish land grant, trialling hundreds of fruits, nuts and vegetables to see what would thrive in California’s Mediterranean climate. Among them he planted rows of Mission olives — the variety Franciscan missionaries had carried up from Mexico — along the edges of the property. The family later gave the ranch to the University of California as a working research farm, on the understanding that the old olive trees would be allowed to live on.

Trees that refuse to quit

What strikes you first is scale and stubbornness. Some of these Mission trees are close to four storeys tall, and though storms and rot have taken limbs over the decades, they keep bearing a useful crop year after year. That is the olive’s great party trick: you can neglect it, forget to water it, prune it badly, and it will still fruit. It is a tree that forgives, which is exactly why it spread across the dry, sunny corners of the New World wherever the Spanish went. By the standards of the Mediterranean, where working olives can be a thousand years old and more, these Californian veterans are barely middle-aged.

A living laboratory

Handed to the university, the old grove became something rarer than a heritage curiosity: a research tool. Scientists could study how century-old Mission trees behave, how their fruit ripens, and what kind of oil they yield. The Mission olive itself is dual-purpose — grown both for the table and for a soft, mild oil — and tasting oils pressed from single old varieties is a way of reading the past through the palate. This kind of patient, unglamorous work underpinned the revival of quality American olive oil, which spent much of the twentieth century as an afterthought behind the canned black ripe olive.

Old roots, new plantings

Inspired by survivors like these, a later generation of California growers went looking for better flavour, importing Tuscan and Spanish cultivars and asking what happens when you cross a little Italy with a lot of sunshine. The answer became a genuine American oil culture: estate mills, harvest-dated bottles, and oils that can stand beside Italian and Spanish ones without apology. It started, in part, with somebody deciding that a stand of gnarled old Mission trees was worth saving rather than clearing.

What to take from the Wolfskill trees

• The Mission olive is California’s heritage variety — mild, dual-purpose, forgiving to grow.
• Old trees can crop for centuries; age is no barrier to a useful harvest.
• Single-variety, harvest-dated Californian oils are the fruit of exactly this research-led revival.
• An olive tree is almost never worth cutting down — renovation beats removal.

The Wolfskill olives: common questions

Drawn from University of California olive-research history and California Mission-olive records.