What is so special about the Cascade-Siskiyou National Monument?

This national monument spans the border between Oregon (Jackson County) and California (Siskiyou County) immediately east of the I-5 freeway. It was first established in 2000 by President Bill Clinton and expanded in January 2017 by President Obama as one of his last actions before leaving office. The monument is managed by the Bureau of Land Management (BLM) from the local Medford Oregon office. It is an important time to learn more about the monument because it is one of the four that Interior Secretary Zinke (Trump administration) has proposed to shrink. 

Several weekends ago, we hiked to Hobart Bluff in the monument with Mike and Chris from the San Francisco Bay Area. This view (with Jay and Mike) is to the northwest, parallel to the Bear Creek arm of the Rogue Valley, with Emigrant Lake in the near part of the valley and the buildings of Ashland just beyond the lakes. To the west of the valley (left side of photo) are the Klamath Mountains that consist of old Paleozoic and Mesozoic, mostly oceanic, rocks that were added to the continent many tens of millions of years ago. To the east of the valley (right side of photo) are the mountains that make up the Western Cascades—the now-eroded volcanoes that were active from about 40–15 million years ago. The currently active volcanoes are located just east of the Western Cascades; although they didn’t show up well in photographs, Mt. McLoughlin volcano was visible to the east and Mt. Shasta volcano was visible to the south.

So why was this area declared a national monument by President Clinton in the first place? Turns out this monument was the first to be recognized solely because of a desire to preserve its incredible biodiversity. In recognition of this biodiversity, the region has also been designated as an Area of Global Botanical Significance and proposed as a World Heritage Site and UNESCO Biosphere Reserve. 

And what is the cause of all this biodiversity, you may ask? Well, it’s all about the geology, of course! This location is at the intersection of the Cascade, Klamath and Siskiyou mountain ranges, with additional climatic influences from the Basin and Range province to the east (starting at Klamath Lake) and the Pacific coast to the west. These rugged mountain ranges are characterized by a complex suite of rock types that creates the various soil types, topographic changes, and micro-climates that produce so many diverse ecological niches. David Rains Wallace’s 1983 book about the natural history of the region (biological and geological), entitled “The Klamath Knot”, produced a visual way (a knot) to think about this complexity.

Clearly, there are many good reasons for preserving the natural environment of this region. As it is, there remain many private holdings within the monument, and the law allows for recreational activities such as hunting and fishing. In fact, our hike was curtailed by gun shots as we attempted to continue south to Soda Mountain. Only very limited commercial interests are likely to benefit from the monument’s shrinkage and it is my hope that the monument will remain at its current size so that more of the public can enjoy its bounty and beauty.

For more information :

—BLM site with photos and useful information: https://www.blm.gov/programs/national-conservation-lands/national-monuments/oregon-washington/cascade-siskiyou

—Site of Friends of the Cascade-Siskiyou National Monument, a group that organizes hikes and other activities in the monument and strives to protect it: http://www.cascadesiskiyou.org/

—World Wildlife Fund’s site about the area’s global significance: https://www.worldwildlife.org/ecoregions/na0516

—Wikipedia site about “The Klamath Knot”: https://en.m.wikipedia.org/wiki/The_Klamath_Knot

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  1. Mark on October 28, 2017 at 5:05 am

    Karen, your blog posts are always so informative, and interesting, and well written. Really great. I did a short paper for school on the Rouge Valley viticultural area, and of course geology (yet again) plays a role, both in terms of topography and soil characteristics. The Rouge Valley is right at the intersection with the Siskiyou and Cascades ranges and makes for a diversity of terriors. We’ll have to open a local bottle (or two) for a more in-depth geological analysis.

    • Landscapes Revealed on October 30, 2017 at 5:10 pm

      Terroir is, indeed, another interesting aspect of the geological diversity! It seems that the region is not known for any one varietal because so many do well here, depending on the specific eco-niche. Come back and drink wine with us!!

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