The Walters Ranch Hop Kiln as it stands today.
It was hops, not grapes, that put Sonoma County on the map. A century ago, the leggy bines grew in the millions. Their cones were dried for worldwide sale in oast houses or hop kilns, distinctive peaked barns with castle-like turrets that hulked like mammoths across the Russian River Valley. But by the end of World War II, the hops business had become a losing game. One by one, the county’s hop kilns disappeared or fell into disrepair. Today, by my count, there are just three left in Sonoma County. My journey to find them begins with one that was erected not to dry the conical pods but to honor their former glory. The sky is moody when I visit Russian River Vineyards in Forestville. Its two weathered wooden towers stand in stark relief against the gloom as if straight from the pages of a fairytale. “The hop kiln was built [between 1975 and 1976] to fit the aesthetics of what the Russian River Valley was,” Gio Balistreri, co-owner and winemaker of Russian River Vineyards, explains to me at a picnic table in the wine garden. The first hops were planted in Sonoma County in 1858. By 1900, the San Francisco Chronicle estimated that there were at least 7,500 acres growing there and in neighboring counties, more than almost anywhere in the U.S.
Unidentified hop kilns with conveyor belt and loading platform in Sonoma County sometime in the early 1900s.
But by the 1970s, when the replica oast house was built at Russian River Vineyards, the hop industry there was long gone. Three major factors led to its downfall: the invention of a mechanical hops harvester in 1940 (by Santa Rosa inventor Florian Dauenhauer), “downy mildew” disease among the plants and finally, the parasitic insect phylloxera. The only thing left of that agricultural chapter are the hop kilns, bones of a species now extinct. “To see a real, historic hop kiln, go to Sonoma-Cutrer Vineyards,” Balistreri tells me. “Look northwest and you’ll see three towers in the distance. Ask at the tasting room if you can drive out to see it.” But as I drive into the estate, there are no towers in the distance. At the tasting room, they tell me I’ve arrived just a few months too late. The dilapidated historic building was structurally unsound, and Sonoma-Cutrerhad no choice but to tear it down a few months ago. The hop kilns raised in Sonoma between 1861 and the early 20th century were constructed in the British tradition from wood, brick or stone. Each had ovens or burners on the ground level and a hops drying floor above. Sacks of the freshly picked crop were poured onto the drying floor in a layer up to 36 inches thick. Over the following eight to 20 hours, they dried out in the rising heat. The warmth escaped the top of the structure through towers capped with “cowls.” In Sonoma, they typically took a cabin-like shape, rectangular with sloped-roofs to keep out wet weather. Most hop kilns had two or three towers, but some were much larger. One at Wohler Ranch near Healdsburg had eight.
Outside Martinelli Winery's hop kilns.
The three-towered Walters Ranch Hop Kiln, built in 1905 by Italian stonemason Angelo Soldini, has been on the California state historic register since the 1970s. Landmark Vineyards bought the property in 2016 and has essentially been restoring the structure ever since. Walking me through the kiln, hospitality manager Donna Carroll explains how nearly everything — from the stone to the ceiling — had to be outfitted, upgraded or resurfaced.
As a result, Landmark’s is the most accurate representation of a turn-of-the-20th-century oast house in Sonoma — though it’s not quite done. A wooden balcony and tower-to-ground ramp are still missing (plus, they haven’t quite decided what to do with the huge tubular oil burners they pulled from the ground floor during construction), but its machinery, slatted floors and cowls look just as they did when the kiln dried its last bales in 1952. Not more than a mile from Landmark, I stumble upon another kiln. The two-towered, red-painted former beauty is now crumbling into the hillside. It’s the only still-standing oast house I’ve discovered in the wild. Undoubtedly, there are others, one or two or three more hiding in plain sight on private land out of the view of the public. But nobody seems to know for sure.
The exterior of the hop kilns at Hop Kiln Winery in Healdsburg in 1981.
Picking hops used to be a family affair. In the late 19th and early 20th centuries, agricultural migrants arrived in the Russian River Valley by the wagonload each September. They lived in camps built in the hopyards and, when not working with the stinging, itchy bines, they socialized, swam and danced. “Some people called it ‘vacation with pay,’” laughs Tessa Gorsuch, estate director at Martinelli Winery and Vineyards. Martinelli’s tasting room was once the bailing barn for the immense three-tower hop kiln next door. There, the dried hops would be rolled on a track and dumped into a device that condensed them into rectangular bricks. Signatures of workers — H. Slama 1937, Jack Poggi 1923, Ed Grimes ’44 — are still etched into the wood. “The hop camp was across the street,” Gorsuch continues. “There was a 12 foot by 12 foot platform where they’d pitch their tents, a general store and a swimming hole.” The last hops were picked in 1957, three years before Gorsuch’s great-uncle purchased the estate.
Graffiti and markings made by hop workers at Martinelli Vineyards.
Sonoma County’s hop industry sputtered out slowly over the mid-20th century. The last major harvest was at Bussman Ranch near Windsor in the 1960s. But agricultural trends come in cycles, says Scott Bice, farm manager at Redwood Hill Farm-Capracopia in Sebastopol. Sonoma’s hops are coming back around, and they’re coming fast. “A few years ago, our hopyard was the biggest in Sonoma,” he told SFGATE over the phone. Bice grows several varieties of the citrusy, piney plant, including comet and Chinook, in his 1.5-acre yard. “Now there are probably three others that are bigger, so it’s definitely a growing industry,” he said, “Our sandy loam soil [in the Russian River Valley] is really ideal for hops.” Unlike the hops grown in Sonoma 100 years ago, Bice doesn’t dry his crop. He sells them “wet” (or fresh), to craft breweries like Fogbelt Brewing in Santa Rosa and Crooked Goat Brewing in Sebastopol, as well as to the flower industry.
Ground floor where burners heated up the hops at Landmark Vineyards.
Thus far, family farms have propelled the re-burgeoning hop industry forward. But Bice expects it to evolve over the next five years to include larger growers who will end up drying their hops, just like the industry’s progenitors once did. We can only hope that the fantastical turreted castles of Sonoma’s beer history will return to the Russian River Valley along with them.
Shoshi Parks is an anthropologist and freelance writer specializing in history, travel and food.