Snake River Valley is Idaho's first American Viticultural Area (AVA) that encompasses an area in

southwestern Idaho Southwestern Idaho is a geographical term for the area along the U.S. state of Idaho's borders with Oregon and Nevada. It includes the populous areas of the Boise metropolitan area and the Treasure Valley. The counties of Ada, Adams, Boise, ...

and two counties in eastern

Oregon Oregon ( , ) is a U.S. state, state in the Pacific Northwest region of the United States. It is a part of the Western U.S., with the Columbia River delineating much of Oregon's northern boundary with Washington (state), Washington, while t ...

. The area was established on April 9, 2007 by the Alcohol and Tobacco Tax and Trade Bureau (TTB),

Treasury A treasury is either *A government department related to finance and taxation, a finance ministry; in a business context, corporate treasury. *A place or location where treasure, such as currency or precious items are kept. These can be ...

after reviewing the petition submitted by Idahoan vintners of the Snake River Valley, the Idaho Grape Growers and Wine Producers Commission, and the Idaho Department of Commerce and Labor, collectively acting as “petitioner” to establish the viticultural area named "Snake River Valley." For wines to bear the "Snake River Valley" label, at least 85% of the grapes used for production must be grown in the designated area, which includes the southwestern Idaho counties of Ada, Adams,

Boise Boise ( ) is the capital and most populous city of the U.S. state of Idaho. As of the 2020 census, there were 235,685 people residing in the city. Located on the Boise River in southwestern Idaho, it is east of the Oregon border and nor ...

Canyon A canyon (; archaic British English spelling: ''cañon''), gorge or chasm, is a deep cleft between escarpments or cliffs resulting from weathering and the erosive activity of a river over geologic time scales. Rivers have a natural tendency t ...

, Elmore, Gem, Gooding,

Jerome Jerome (; ; ; – 30 September 420), also known as Jerome of Stridon, was an early Christian presbyter, priest, Confessor of the Faith, confessor, theologian, translator, and historian; he is commonly known as Saint Jerome. He is best known ...

, Owyhee, Payette, Twin Falls, and

Washington Washington most commonly refers to: * George Washington (1732–1799), the first president of the United States * Washington (state), a state in the Pacific Northwest of the United States * Washington, D.C., the capital of the United States ** A ...

, and the Eastern Oregon counties of Malheur and

Baker A baker is a tradesperson who baking, bakes and sometimes Sales, sells breads and other products made of flour by using an oven or other concentrated heat source. The place where a baker works is called a bakery. History Ancient histo ...

. The appellation, when established, was resident to 15 wineries and 46 vineyards with under vine.

History

Idaho was resident to the first wineries in the Pacific Northwest in the 1800s.

Vitis vinifera ''Vitis vinifera'', the common grape vine, is a species of flowering plant, native to the Mediterranean Basin, Mediterranean region, Central Europe, and southwestern Asia, from Morocco and Portugal north to southern Germany and east to northern ...

were first planted in the state by French

immigrants Immigration is the international movement of people to a destination country of which they are not usual residents or where they do not possess nationality in order to settle as permanent residents. Commuters, tourists, and other short- ...

Louis Desol and Robert Schleicher, and Jacob Schaefer from

Germany Germany, officially the Federal Republic of Germany, is a country in Central Europe. It lies between the Baltic Sea and the North Sea to the north and the Alps to the south. Its sixteen States of Germany, constituent states have a total popu ...

before grapes were ever planted in

and

. Idaho viticulture flourished after the passage of the Homestead Act of 1862, granting tracts of land to farmers in sparsely populated western territories. As a result, Idaho wines received awards and gained national recognition before

Prohibition Prohibition is the act or practice of forbidding something by law; more particularly the term refers to the banning of the manufacture, storage (whether in barrels or in bottles), transportation, sale, possession, and consumption of alcoholic b ...

crippled the industry and shutdown production. In fact, Idaho issued a state

prohibition Prohibition is the act or practice of forbidding something by law; more particularly the term refers to the banning of the manufacture, storage (whether in barrels or in bottles), transportation, sale, possession, and consumption of alcoholic b ...

in 1916 before the 18th Amendment was enacted in 1920 and

repealed A repeal (O.F. ''rapel'', modern ''rappel'', from ''rapeler'', ''rappeler'', revoke, ''re'' and ''appeler'', appeal) is the removal or reversal of a law. There are two basic types of repeal; a repeal with a re-enactment is used to replace the law ...

in 1933. The state's viticulture industry was not revived until the 1970s when grape vines were planted in the Snake River Valley toward the southern part of the state.

Terroir

Topography

The ancient Lake Idaho is the physical focus and an important distinguishing feature of the Snake River Valley viticultural area. Ancient Lake Idaho was a trough-like structure of deep lakes that filled the western part of the Snake River Valley, also known as "

Snake River Plain The Snake River cutting through the plain leaves many canyons and Canyon#List of gorges, gorges, such as this one near Twin Falls, Idaho The Snake River Plain is a geology, geologic feature located primarily within the U.S. state of Idaho. ...

", approximately 4 million years ago. The Snake River Plain, a crescent-shaped belt of lava and sediment ranging from wide, extends about in length across southern Idaho. The geology of the western portion of the Snake River Plain has lower elevations and a rift-bounded basin, which contrast to the higher elevations of the eastern section of the Snake River Plain. Also, according to the petitioner, the colder and drier climate of the eastern area is not conducive to successful viticulture, unlike the warmer weather and lower elevations of ancient Lake Idaho. The geologic history of the Snake River Valley viticultural area includes flood basalts, northwest-trending structures, loess mantles, and outburst floods. The ancient Lake Idaho extends northwest to southeast as a system of lakes and flood plains, from the Oregon-Idaho State line to west of Twin Falls, Idaho. North of the Snake River Valley viticultural area boundary line, the petitioner explains, are

Cretaceous The Cretaceous ( ) is a geological period that lasted from about 143.1 to 66 mya (unit), million years ago (Mya). It is the third and final period of the Mesozoic Era (geology), Era, as well as the longest. At around 77.1 million years, it is the ...

granites of the Idaho

Batholith A batholith () is a large mass of intrusive rock, intrusive igneous rock (also called plutonic rock), larger than in area, that forms from cooled magma deep in the Earth's crust. Batholiths are almost always made mostly of felsic or intermediate ...

Eocene The Eocene ( ) is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (Ma). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''Eocene'' comes ...

volcanoes, older sedimentary rocks, and volcanic flows. The Snake River Valley viticultural area boundary encircles the now dry, ancient Lake Idaho, a low elevation, fault-bounded, rift basin with a relatively flat, sedimentary bottom. To the south of the boundary line, volcanic rocks overlie the southern extension of the granite basement. The surrounding areas have a mountainous topography with generally higher elevations. Lower elevations, between when compared to the surrounding mountains and the eastern portion, is a significant distinguishing feature of the Snake River Valley viticultural area, as shown on the

United States Geological Survey The United States Geological Survey (USGS), founded as the Geological Survey, is an agency of the U.S. Department of the Interior whose work spans the disciplines of biology, geography, geology, and hydrology. The agency was founded on Mar ...

(USGS) maps and described by the petition.

Oxbow Dam Oxbow Dam is a hydroelectric run-of-the-river rockfill dam in the western United States, on the Snake River in Hells Canyon ( river mile 273) along the Idaho-Oregon border. Description Completed in 1961, the dam is part of the Hells Canyon ...

, along the

Snake River The Snake River is a major river in the interior Pacific Northwest region of the United States. About long, it is the largest tributary of the Columbia River, which is the largest North American river that empties into the Pacific Ocean. Begin ...

in Adams County, Idaho, lies at an elevation , but the encircling viticultural area boundary line generally adheres to an elevation , according to the boundary outlined in the petition. The boundary line deviates from its prescribed elevation twice at the northernmost boundary on the McCall map and again along the western boundary of the

Vale A vale is a type of valley. Vale may also refer to: Places Georgia * Vale, Georgia, a town in the Samtskhe-Javakheti region Norway * Våle, a historic municipality Portugal * Vale (Santa Maria da Feira), a former civil parish in the municip ...

map. The petitioner explains that the contour line, past the boundaries of the McCall and Vale maps, continues into regions not associated with the Snake River Valley or with viticulture. The region's viticulture, according to the petitioner, is successful between elevations of . Mountains surrounding the western Snake River Valley region exceed , especially to the east of the viticultural area boundary line in the

Boise National Forest Boise National Forest is a United States National Forest, National Forest covering of the U.S. state of Idaho. Created on July 1, 1908, from part of Sawtooth National Forest, it is managed by the United States Forest Service, U.S. Forest Se ...

, as shown on the

Idaho City, Idaho Idaho City is a town in, and the county seat of, Boise County, Idaho, Boise County, Idaho, United States, located about northeast of Boise, Idaho, Boise. The population was 466 at the 2020 United States census, 2020 census. Idaho City is part ...

, USGS map. The City of

Twin Falls, Idaho Twin Falls is the county seat of and the largest city in Twin Falls County, Idaho, United States. The city had a population of 51,807 as of the 2020 United States census, 2020 census.

, about southeast of the Snake River Valley viticultural area's eastern boundary line, as shown on the USGS Twin Falls, Idaho, map, lies at an elevation of , or about higher than the elevation of the viticultural area boundary line. The petitioner provided three topographic profiles of the Snake River Valley viticultural area drawn from various points of the compass. The three profiles include (1) California Mountain, Oregon, to

Bruneau, Idaho Bruneau is a Census-designated place in Owyhee County in the southwestern part of the U.S. state of Idaho. The mouth of the Bruneau River is to the northwest and Bruneau Sand Dunes State Park is to the east. As of 2014, Bruneau has a populatio ...

, (2) Oreana, Idaho, to Danskin Peak, Idaho, and (3)

Marsing, Idaho Marsing is a city in Owyhee County, Idaho, United States. The population was 1,031 at the time of the 2010 census. It is part of the Boise metropolitan area. Geography Marsing is on the Snake River, which forms the border with Canyon County ...

, to Emmett, Idaho. The profiles show the lower elevations of the ancient Lake Idaho basin in comparison to the surrounding higher mountain elevations beyond the viticultural area boundary line. Payette, Idaho, is at an elevation of about in the basin, but California Mountain, Oregon, reaches a height of approximately , significantly higher than the viticultural area boundary lines.

Climate

The distinguishing climatic features of the Snake River Valley viticultural area, include precipitation, air temperature, heat-unit accumulation, and growing season length. The factors affecting climate include the region's topography, a basin depression with surrounding mountainous terrain; the continental inland location approximately east of the

Cascade Range The Cascade Range or Cascades is a major mountain range of western North America, extending from southern British Columbia through Washington (state), Washington and Oregon to Northern California. It includes both non-volcanic mountains, such as m ...

; and the 43 degree north latitude line. The petitioner adds that the Snake River Valley viticultural area is in a climatic transition zone with both continental and maritime regimes. The combination of elevation and latitude of the Snake River Valley viticultural area creates a shorter grape-growing season than those in many other viticultural regions in the

Western United States The Western United States (also called the American West, the Western States, the Far West, the Western territories, and the West) is List of regions of the United States, census regions United States Census Bureau. As American settlement i ...

. Climatic data from four weather stations in the West Snake River Valley (WSRV) and for other grape-growing districts in the Western United States are noted in the climatic data table below. The petitioner used online data from 1971 to 2000 compiled and archived by the National Climatic Data Center (NCDC) and

National Oceanic and Atmospheric Administration The National Oceanic and Atmospheric Administration (NOAA ) is an American scientific and regulatory agency charged with Weather forecasting, forecasting weather, monitoring oceanic and atmospheric conditions, Hydrography, charting the seas, ...

, for four areas within the Snake River Valley viticultural area and for three viticultural regions outside of Idaho. The petition averaged the collected data for the four Idaho weather stations listed in the climatic data table below. The data are listed separately in the table for each station outside of Idaho, including Umpqua Valley,

; Walla Walla Valley,

; and

Napa Valley Napa Valley is an American Viticultural Area (AVA) in Napa County, California. The area was established by the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) on February 27, 1981, after a 1978 petition submitted by the Napa Valley Vin ...

California California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...

, all of which are within established American Viticultural Areas.

Precipitation

Snake River Valley is a semiarid desert with minimal summer precipitation. The viticultural area has a mean annual precipitation of , occurring mostly in winter. The low precipitation rate combines with warm weather during the growing season, and the vineyards, therefore, need irrigation. According to the petitioner, the Idaho weather stations within the Snake River Valley viticultural area record about half the annual precipitation of the weather stations at Umpqua Valley, Oregon; Walla Walla Valley, Washington; and Napa Valley, California. The petitioner explains the lower annual precipitation of Snake River Valley viticultural area may be partially due to the

rain shadow A rain shadow is an area of significantly reduced rainfall behind a mountainous region, on the side facing away from prevailing winds, known as its leeward side. Evaporated moisture from body of water, bodies of water (such as oceans and larg ...

s of the Cascade,

Sierra Nevada The Sierra Nevada ( ) is a mountain range in the Western United States, between the Central Valley of California and the Great Basin. The vast majority of the range lies in the state of California, although the Carson Range spur lies primari ...

, and Owyhee Ranges.

Temperature

The Snake River Valley viticultural area's mean annual temperature, based on an average of the four Idaho stations monitored, is , or . The mid-winter mean temperatures are below for several months, and potential vineyard damage is a hazard, the petitioner explains. The California, Oregon, and Washington weather stations listed in the climatic data table above record warmer average winter temperatures. The differences in the extreme winter temperatures and the mean annual temperature ranges between the Snake River Valley viticultural area and the three weather stations monitored in California, Oregon, and Washington show significant variations in viticultural growing conditions. The petitioner explains that the difference in winter temperatures between the colder Snake River Valley viticultural area and the stations at Umpqua Valley, Oregon; Walla Walla Valley, Washington; and Napa Valley, California, results, to a great extent, from the higher elevations in the viticultural area, which are between . Elevations of the other stations are Umpqua Valley, about ; Walla Walla Valley, ; and Napa Valley, . Also, distances from the Pacific Ocean affect the amount of moderating, marine air temperatures the seven weather stations receive. Oceans tend to moderate air temperatures over land; hence, a wider annual temperature range indicates a greater degree of continental influence, or distance from an ocean. The Snake River Valley viticultural area and the Walla Walla Valley both have, as a measure of continental influence, mean annual temperature ranges of about . In comparison, the Umpqua Valley and the Napa Valley, both of which are closer to the Pacific Ocean and are at low elevations, have a smaller mean annual temperature range—about . The temperatures of Snake River Valley viticultural area, according to the petitioner, rise rapidly during the growing season, from June through August. The Umpqua Valley in Oregon and the Snake River Valley viticultural area have similar, annual, total growing degree-days, as shown in the climatic data table above; but, they have between 200 and 250 fewer heat units than the Walla Walla Valley, Washington, and the Napa Valley, California. Each degree that a day's mean temperature is above , which is the minimum temperature required for grapevine growth, is counted as 1 degree-day. The length of the Snake River Valley viticultural area's growing season correlates to the frost-free period from about May 10 to September 29 annually, according to the petitioner. The total measurement of annual viticultural growth is between 64 and 117 days less than that measured at Walla Walla Valley, Washington; Umpqua Valley, Oregon; and Napa Valley, California. Located on the same

latitude In geography, latitude is a geographic coordinate system, geographic coordinate that specifies the north-south position of a point on the surface of the Earth or another celestial body. Latitude is given as an angle that ranges from −90° at t ...

as Oregon's Umpqua Valley AVA, the Snake River Valley has a more drastic

diurnal temperature variation In meteorology, diurnal temperature variation is the variation between a high air temperature and a low temperature that occurs during the same day. Temperature lag Temperature lag, also known as thermal inertia, is an important factor in diur ...

than other

appellations An appellation is a legally defined and protected geographical indication used to identify where the ingredients of a food or beverage originated, most often used for the origin of wine grapes. Restrictions other than geographical boundaries, ...

in the

Pacific Northwest The Pacific Northwest (PNW; ) is a geographic region in Western North America bounded by its coastal waters of the Pacific Ocean to the west and, loosely, by the Rocky Mountains to the east. Though no official boundary exists, the most common ...

due to the high

elevation The elevation of a geographic location (geography), ''location'' is its height above or below a fixed reference point, most commonly a reference geoid, a mathematical model of the Earth's sea level as an equipotential gravitational equipotenti ...

of most of the appellation's vineyards. At elevations of

above sea level Height above mean sea level is a measure of a location's vertical distance (height, elevation or altitude) in reference to a vertical datum based on a historic mean sea level. In geodesy, it is formalized as orthometric height. The zero level ...

, the region's is also more than from the tempering effects of the

Pacific Ocean The Pacific Ocean is the largest and deepest of Earth's five Borders of the oceans, oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean, or, depending on the definition, to Antarctica in the south, and is ...

Soil

The soils of the Snake River Valley viticultural area are described as being diverse and not a distinguishing feature, because the soils have developed in various parent materials, during various time frames, and under varying climatic conditions. The soils are broadly classified as

Aridisols Aridisols (or desert soils) are a soil order in USDA soil taxonomy. Aridisols (from the Latin ''aridus'', for "dry", and ''solum'') form in an arid or semi-arid climate. Aridisols dominate the deserts and xeric shrublands, which occupy about on ...

, the petitioner adds, and no single soil series or association is dominant. Vineyards within the Snake River Valley viticultural area are on soils that have underlying parent material derived from weathered sediment from the ancient Lake Idaho, according to the petition. At the surface are loess, sand, and, in slack water areas, flood-deposited silt. Typically, slope vineyards in the area are on very shallow soils.

Wine Industry

According to the Idaho Wine Commission, the Gem State is one of the fastest-growing wine regions in the United States. In 2013, Idaho's wine industry had a $169.3 million impact, up from $73 million just five years before. There were 40 wineries in Idaho in 2011, and by 2022 that number increased 75%. There are over 70 wineries in Idaho, with the largest and oldest winery being Snake River Valley's St Chapelle, founded 1975, in Caldwell. The state's economy was boosted $210 million by its wine industry in 2022, and as Idaho keeps growing, so will that number. Vineyards with elevations up to have an extended growing season, similar to Argentina's Uco Valley, home to some of the "world's best" Malbecs. Riesling and Malbec, both are perfectly suited for southern Idaho's hilly terrain. Rhône varieties such as Syrah, Viognier, Petite Sirah and Grenache-Syrah-Mourvèdre blends also are wines to notice, as well as Petit Verdot and Tempranillo are keys to Idaho viticulture's success.

References

External links