Yorkville Highlands was approved as an AVA in 1998 because of its distinctive soils and temperatures relative to neighboring Anderson Valley. Yorkville Highlands’ rocky soils, with high-gravel content, differ from the loamy, clay soils common to neighboring appellations. These highly-porous soils allow for superior water drainage, forcing the roots of vines to dig deep for water. The result is low-vigor vines that yield concentrated fruit. The moderate temperatures of the AVA are suitable for Sauvignon Blanc, but also show great promise for Bordeaux reds like Cabernet Sauvignon and Merlot. More information is available at Yorkville Highlands Growers and Vintners Association