Map of the Cascade range by Shannon, via Wikimedia Commons.
CSW Students might know a bit about the Cascade Mountain Range. They know that the majority of Washington State’s vineyards are planted to the east of, and in the rain shadow of, the Cascades.
They also know that one of the main differences between the geography of Washington State’s wine industry and Oregon’s wine industry is that in contrast, the majority of Oregon’s vineyards are located to the west of the Cascades, sheltered from the effects of the Pacific Ocean by the much tamer mountains of the 200 mile-long Oregon Coast Range. And they have probably heard of the Columbia Gorge, as it’s a tiny AVA that straddles the Oregon and Washington State lines.
And that’s a pretty good start, but there is so much more to know…
The Cascade Range is impressive, stretching for over 800 miles from Mount Lytton in British Columbia, through Cascades National Park in Washington State, past Mount Hood in Oregon, and ending just south of Mount Lassen in Northern California’s Shasta County. The highest peak in the Cascades is Washington State’s Mount Rainier, which rises to 14,411 feet above sea level and dominates the surroundings for miles around. Mount Saint Helens, whose 1980 eruption transformed a mountain with a 9,677 foot tall summit into an 8,365 foot high mountain with a 1 mile-wide horseshoe-shaped crater, is also part of the Cascade Range.
The range, particularly in the area north of Mount Rainier, is extremely rugged. Many of the smaller mountains in this area are steep and glaciated, looming over the low valleys below. The topography settles down a bit as the range winds southward, but even its southernmost peak, Mount Lassen, rises 5,229 feet above its surroundings to an elevation of 10,457 feet above sea level.
Mount Saint Helens, post her 1980 eruption
Due to its proximity to the Pacific Ocean and its westerly winds, the Cascades form a rain shadow for much of the inland Pacific Northwest. The areas to the west of the mountains are known for rainy conditions, and as the elevation climbs, for year-round snow and ice. The western slopes of the Northern Cascades can have annual snow accumulations of up to 500 inches, and with accumulation of over 1,000 inches in exceptional years.
In comparison, on the arid plateau located to the east of the mountains, annual rainfall averages 9 inches. This area, now known as the Columbia River Plateau, was formed over 16 million years ago as the lava flows from Cascade volcanoes coalesced, and covers a 200,000 square mile region in eastern Washington, Oregon, Northern California and Idaho. As all good wine students know, this is the area where almost all of Washington State’s commercial vineyards are planted.
The Columbia Gorge, located where the Columbia River forms the border between Oregon and Washington State, is the only major break in the American section of the Cascade Mountains. The Gorge was formed over the millennia as the Columbia River eroded its way through the burgeoning mountains on its way to the Pacific off of the Columbia Plateau. Lewis and Clark, in 1805, were able to reach the Pacific through the impressive Cascades via the Columbia Gorge, which for many years was considered the only practical passage through the surrounding mountains.
Vineyards in the Columbia River Gorge
In Canada, the country’s second largest wine region, The Okanagan, is also located in the rain shadow of the Cascade Range. The region, which stretches for 100 miles north of the US border with Washington State, shares many of the same geographical/geological features that define viticulture in Washington State, such as a continental climate (somewhat moderated by Lake Okanagan), long daylight hours in the growing season (due to the northerly latitudes), an average of 9 inches of rain per year (requiring irrigation), and the risk of frost damage to the vines over the cold winters.
Other people may note that the majestic Cascades are known for ski resorts, hydro-electric power, strong westward rivers, Douglas Fir trees, important water reserves, Klamath Falls, alpine elk, glaciers, grizzly bears, blueberries, and some of the few remaining wild wolf packs in North America… but for some of us, it’s all about the wine!
The Bubbly Professor is “Miss Jane” Nickles of Austin, Texas: email@example.com
This post was inspired by week ten of my Online CSW Prep Class!