Issue link: https://digital.copcomm.com/i/913027
40 { THE SOMM JOURNAL } DECEMBER/JANUARY 2017/2018 { soil types } THE BORDERS OF THE Russian River Valley AVA are defined by climate and weather. Soft, misting fog released from the Pacific Ocean shrouds the valley to create perfect growing conditions for the fine wine vinifera of Pinot Noir and Chardonnay. As the French have been preaching for a thousand years, terroir is so much more than just the weather. The very core of the word—terra—speaks to the importance of the earth in which the vines grow. The roots run deep in the Russian River Valley, and the array of soils present speaks to the complexity of the region. For millions of years, the North American and Pacific tectonic plates have ground against one another, creating friction and raising bedrock to the surface. This tension created the Mayacamas Mountains and released some of the Earth's hidden energy through volcanic vents. Over time, these vents piled layers of ash over the shallow sea that once covered the valley. That sea receded between 3 and 5 mil - lion years ago, leaving behind the unique blend of volcanic and sandy soils we now call Goldridge. The combination of low soil fertility and excellent drainage allows wine - makers and vineyard managers complete control over water and nutrient manage- ment. Goldridge soil is most commonly associated with the small Green Valley sub-AVA, though it does extend into the greater Russian River Valley. Pinot Noir and Chardonnay thrive in this Goldridge soil, though experimentation with Zinfandel and Rhône varieties is also showing promise. In the western section of the AVA, we find massive amounts of Hugo gravelly loam. This well-draining soil accounts for the greatest propor tion of the valley, covering roughly 20 percent of the total landmass. Hugo is found along the slopes in the steep hills around the towns of Forestville and Guerneville. While vinifera vines are planted here, it seems that the great redwoods have taken to Hugo more so than the grapevines themselves. On the opposite side of the valley in the foothills of the Mayacamas, we find the Chalk Hill sub-AVA. Chalk Hill is a bit of a misnomer, as it actually has no chalk in its soil; the white coloring instead comes from the quar tzite-rich volcanic ash that covers the area, a result of eruptions from Mount Saint Helena. This volcanic soil is very nutrient poor, which forces vines to struggle and helps to control vigor. Here we see greater diversification in grape plantings; Sauvignon Blanc, Cabernet Sauvignon, Merlot, and Cabernet Franc join Chardonnay as leading varieties. A slew of other soil types enrich the landscapes of the Russian River Valley: Steinbeck, Huichica, Haire, Arbuckle, and Zamora, to name a few. Each speaks through the wine to truly give the Russian River Valley its own signature of unparal - leled diversity and individuality. Diverse Terra-tory UNEARTHING THE SOIL PROFILE OF THE RUSSIAN RIVER VALLEY AVA by Peter Wilke PHOTO BY CHRIS BEVERLY2070 VIA THINKSTOCK