When you’re swirling a glass of Dry Creek Valley wine around, pinpointing certain aromas in the nose, are you thinking about dirt? Probably not, since wine is often viewed in such a romantic sense that something as primal as dirt or soil isn’t mentioned outside of wine geek circles.

But soil plays an integral – some would even argue the most important – part in the winemaking process. Differences in soil are what gives a certain grape a unique characteristic that will end up in the bottle. For example, chalky soils may impart a minerality to the wines made from the grapes grown in it.

Dry Creek Valley boasts 25 soil series and 75 soil variations, creating a patchwork of soils, each of which impart unique characteristics into the fruit they bear. We’ve listed four of the more common soil types below; next time you open up a bottle from Dry Creek Valley, see if you can sense the unique contribution the soil has made to the wine.

Yolo loam is a well-drained soil derived from sedimentary rock deposits typically found on the valley floor. In Dry Creek Valley, grape varieties such as Sauvignon Blanc and Chardonnay are commonly grown in this soil series, which impart a minerality that complements the crispness of these wines.

Manzanita loam is a well-drained soil derived from basic igneous rock (rock is formed through the cooling and solidification of magma or lava) found commonly on a terrace or a bench. Cabernet Sauvignon and Zinfandel are commonly grown in Manzanita loam, and the wines produced tend to age well and have a great mouthfeel- characteristics imparted by this soil series.

Boomer loam is a well-drained soil derived from metavolcanics (rocks first formed by volcanoes, then recrystalized after being subjected to high pressure and temperatures brought by rocks forming on top) commonly found in hills and mountains. Grapes grown in this soil, found on steeply sloped hills, yield bold, red wines high in tannin and color.

Zamora silty clay loam is a well-drained soil derived from sedimentary rock commonly found in alluvial fans, which are fan-shaped deposits of sediment crossed and built up by streams. Zinfandel and Cabernet Sauvignon are commonly grown in this nutrient rich soil, which lends fruity characteristics to the resulting wines.