Diamond Mountain Viticultural District
Area
The viticulture area of the Diamond Mountain District is located in Napa County, California. The northeastern boundary follows the 400-foot contour line parallel to Highway 29, north of St Helena, to Petrified Forest Road west of Calistoga then southwest along Petrified Forest Road to the Sonoma County line. After following the Sonoma County Line to the boundary of the Spring Mountain Viticulture Area the boundary turns east to the 400-ft. contour line.
The Diamond Mountain District is situated on the eastern slope of the Mayacamas Mountains. The region consists entirely of residual upland soils derived from volcanic parent material. These soils are very different from the alluvial soils on the floor of the Napa Valley to the east and northeast and are also significantly different from the sedimentary upland soils prevalent in the Spring Mountain viticulture area to the south. The soils in Sonoma County to the west and southwest are shallow and dry.
The viticulture area&rsquos; topography and aspect contribute to a special microclimate. Hillside topography and valley temperature inversions combine to give the region an unusually moderate temperate regime during the growing season, with lower maximum temperatures and higher minimum temperatures than nearby on the valley floor. The microclimate of the Diamond Mountain region is clearly distinctive when compared to the surrounding areas. The region is greatly influenced by northeastern aspects, and the cooling effect of the marine breezes from the Pacific Ocean.
The eruption of Mt. Konocti on the south shore of Clear Lake eight million years ago is credited with contributing those crystals along with great quantities of volcanic ash to the Diamond Mountain&rsquos; soil composition. Jacob Schram was one of the first valley settlers to recognize the potential of the Diamond Mountain &lsquos; soil to produce the classic red wines similar to those produced in the famous steep hillside vineyards of Europe. There are currently thirteen growers and seven wineries with vineyards in the Diamond Mountain District. Because of the steep hillsides and deep canyons there are few opportunities to increase the 500 acres presently planted to vines out of the total of 5000 acres in the District.
The viticulture area of the Diamond Mountain District is located in Napa County, California. The northeastern boundary follows the 400-foot contour line parallel to Highway 29, north of St Helena, to Petrified Forest Road west of Calistoga then southwest along Petrified Forest Road to the Sonoma County line. After following the Sonoma County Line to the boundary of the Spring Mountain Viticulture Area the boundary turns east to the 400-ft. contour line.
The Diamond Mountain District is situated on the eastern slope of the Mayacamas Mountains. The region consists entirely of residual upland soils derived from volcanic parent material. These soils are very different from the alluvial soils on the floor of the Napa Valley to the east and northeast and are also significantly different from the sedimentary upland soils prevalent in the Spring Mountain viticulture area to the south. The soils in Sonoma County to the west and southwest are shallow and dry.
The viticulture area&rsquos; topography and aspect contribute to a special microclimate. Hillside topography and valley temperature inversions combine to give the region an unusually moderate temperate regime during the growing season, with lower maximum temperatures and higher minimum temperatures than nearby on the valley floor. The microclimate of the Diamond Mountain region is clearly distinctive when compared to the surrounding areas. The region is greatly influenced by northeastern aspects, and the cooling effect of the marine breezes from the Pacific Ocean.
The eruption of Mt. Konocti on the south shore of Clear Lake eight million years ago is credited with contributing those crystals along with great quantities of volcanic ash to the Diamond Mountain&rsquos; soil composition. Jacob Schram was one of the first valley settlers to recognize the potential of the Diamond Mountain &lsquos; soil to produce the classic red wines similar to those produced in the famous steep hillside vineyards of Europe. There are currently thirteen growers and seven wineries with vineyards in the Diamond Mountain District. Because of the steep hillsides and deep canyons there are few opportunities to increase the 500 acres presently planted to vines out of the total of 5000 acres in the District.