The Russian River Valley AVA
The Russian River Valley became a recognized American Viticultural Area (AVA) in 1983. In 2005, the AVA was expanded by the government from 30,200 acres to 126,600 acres, of which 15,000 acres are planted to premium wine grapes. Presently the Russian River Valley AVA covers approximately 150 square miles within Sonoma County’s borders, and is home to 150 wineries.
The Russian River Valley is shaped by two important factors — weather and geology. A deep Pacific Ocean marine layer in the form of fog typically moves into the region during the summer growing season, providing optimum temperatures for producing world-class pinot noir and chardonnay. This natural air-conditioning allows the grapes to develop to full maturity, retaining much of the natural acidity that might otherwise be lost to heat spikes, such as those farmed in California’s interior valleys.
The second most important factor in shaping the wines of the Russian River Valley is the region’s wide variety of alluvial soils. The gravel, loam and sandy soils found along the river valley have been transported to the area and deposited along the river’s path in several ways. Much of this soil is made up of alluvial materials or weathered sandstone.
Over the past 10 million years, the collisions between the North American and Pacific tectonic plates have caused great uplift in the region’s ancient bedrock. Over the millennia, this bedrock has been eroded and washed by receding oceans and river flooding. The ebbing and flowing of massive glaciers played a role in grinding and pushing rock and soil from other areas into this region. (Since the planet first formed, there have been five major glacial periods where ice covered significant portions of the Northern Hemisphere.)
With the volcanic activity and general instability in the Earth’s surface on what is now known as the Mayacamas Mountains, a thick layer of volcanic ash and lava moved into nearby shallow seas. Evidence of pyroclastic flows can be found on Sonoma Mountain and Mount Saint Helena. This volcanic rock combined with the alluvial material brought here either through flooding, the air, glaciers, or receding seas are found throughout the Russian River Valley. Some of these rocks and soils have been washed and re-washed over millions of years into a gritty, loamy sandstone, known as Goldridge soil. Goldridge, a relatively “old” soil in geologic terms, is most prized by vintners within the Russian River Valley AVA for its fine loam character and moderate drainage.
When you combine all the other alluvial sand/clay/loam soils found in the region, such as Zamora, Arbuckle, Yolo, Haire, and Cortina, there are more variations in soil types in the Russian River Valley than in all of France. This is undoubtedly one of the reasons why, in addition to pinot noir and chardonnay, so many grape varieties grow exceedingly well in the region.
Though it is generally agreed in scientific terms that a soil cannot impart flavors to a wine, a soil clearly enhances the character of a grapevine and the fruit that grows on that vine. When all the elements of winegrowing come together — choosing the right grape variety and clonal selection, matching the soil type, and ensuring there is proper moisture content and position to sunlight — a certain magic occurs. In France, winery vignerons have one word to describe this interaction with the environment — terroir.
At J Vineyards & Winery, the journey of wine excellence and appreciation of our terroir has only just begun. In geologic terms, we are still in the embryonic stage. The wide variety of alluvial soils found in our 257-acres of Russian River Valley estate vineyards have been forming for millions of years and have revealed themselves to us as a major asset in our winemaking endeavors.
J Founder and President, Judy Jordan, holds a degree in Earth Sciences/Geology from Stanford University and knows something about rocks and soil. Her passion for the land and understanding of what goes into making world-class wines holds no bounds. Accompanying Judy on this exploration of wine excellence are veteran Winemaker, Melissa Stackhouse (UC Davis), and Viticulturist, John Erbe. Both have become knowledgeable experts on all aspects of our Russian River Valley terrain, and their dedication shines through in all J wines.