North America.

California.

Alameda County.
This area, situated near San Francisco Bay, contains 1600 acres of vineyards of which about three quarters are dedicated to producing white wines. Most of the vineyards are located in the Livermore Valley. About half the white wine produced is Chardonnay, with significant amounts also of Cabernet Sauvignon and Sauvignon Blanc.

Amador County.
The Sierra Foothills have a warm climate, particularly suited for growing the Zinfandel grape. This is a red grape variety common mainly to California, and is robust, fruity and full of tannin. Zinfandel accounts for over 1600 acres of vines, dwarfing the other production of mainly Sauvignon Blanc and Barbera.

Lake County.
Lake county, named because it contains Clear Lake - the largest lake in California - has over 3500 acres under vine. Production is almost 50/50 between red and white wines. The majority of varieties produced are Sauvignon Blanc and Chardonnay for the whites and Cabernet Sauvignon and Zinfandel for the reds.

Madera County.
This is the second largest producer in California, with nearly 40000 acres of vineyards. By far the most planted variety is Colombard, but varying amounts of Chenin Blanc, Grenache, Carigane and Barbera exist.

Mendocino County.
Situated on the north Californian coast, this county has 13000 acres of vineyards. Varying temperatures along the river valley result in a wide variety of grape varieties proliferating, including Zinfandel, Cabernet Sauvignon, Petite Sirah, Chardonnay, Sauvignon Blanc and Carignane.

Monterey County.
This county produces over half of all the Riesling grown in California in nearly 30000 acres of vines.

Napa County.
The majority of vineyards in Napa County are in the Napa Valley. There are over 200, making this county arguably the most important producer in the states. Of over 35000 acres of vines, over half is dedicated to Chardonnay and Cabernet Sauvignon. Others include Merlot, Sauvignon Blanc and Pinot Noir.

San Joaquin County.
Part of the Central Valley, this county still contains many rarer grape varieties including Alicante Bouschet, Mission and Palomino. However, the majority of its 40000 acres of vines are given over to Zinfandel, Chardonnay, French Coumbard, Cabernet Sauvignon and Chenin Blanc.

San Luis Obispo County.
A fairly small region, producing around 10000 acres of vines. Most wines are reds, such as Cabernet Sauvignon, Zinfandel and Merlot.

Santa Barbera County.
Again, a small county with only 8000 acres, the predominant varieties are white; Chardonnay, Johannisberg Riesling, Sauvignon Blanc and Chenin Blanc are common.

Sonoma County.
With over 36000 acres under vine, this is larger than Napa County. Over two thirds of the grapes grown are Chardonnay, with exceptional examples coming from Dry Creek valley. Cabernet Sauvignon, Zinfandel and Pinot Noir are also common.


Washington.

Washington is the second largest wine producing state in the states (behind California, natch), with 13000 acres of vines. Predominant growing areas are the Yakima Valley, Walla Walla Valley and Columbia Valley. The red / white ratio is almost half each; Chardonnay, Johannisberg Riesling, Merlot and Cabernet Sauvignon are well represented.


Oregon.

Oregon has one of the longer histories of wine making in the states, and is steadily increasing its output. Current vine coverage is about 8000 acres. The three principle valleys are Umpqua Valley, Willamette Valley and Rogue River Valley. The main varietals are Pinot Noir, Chardonnay and Riesling.