Editing Sierra Nevada (section)

===Conservation===
{{see also|Protected areas of the Sierra Nevada}}
[[File:General Sherman tree looking up.jpg|thumb|upright|The [[General Sherman Tree]], a [[Sequoiadendron giganteum|giant sequoia]] in [[Sequoia National Park]], is the world's largest tree by volume.]]

The tourism potential of the Sierra Nevada was recognized early in the European history of the range. [[Yosemite Valley]] was first protected by the federal government in 1864. The Valley and [[Mariposa Grove]] were ceded to [[California]] in 1866 and turned into a state park.<ref name="Schaffer"/> John Muir perceived [[overgrazing]] by [[domestic sheep|sheep]] and logging of [[Sequoiadendron giganteum|giant sequoia]] to be a problem in the Sierra. Muir successfully lobbied for the protection of the rest of Yosemite National Park: Congress created an Act to protect the park in 1890. The Valley and Mariposa Grove were added to the Park in 1906.<ref name="Schaffer" /> In the same year, [[Sequoia National Park]] was formed to protect the Giant Sequoia: all logging of the Sequoia ceased at that time.

In 1903, the city of [[San Francisco]] proposed building a [[hydroelectric dam]] to flood [[Hetch Hetchy Valley]]. The city and the [[Sierra Club]] argued over the dam for 10 years, until the [[U.S. Congress]] passed the [[Raker Act]] in 1913 and allowed dam building to proceed. [[O'Shaughnessy Dam (California)|O'Shaughnessy Dam]] was completed in 1923.<ref>{{cite book |title=Dam!: Water, Power, Politics, and Preservation in Hetch Hetchy and Yosemite National Park |last=Simpson |first=John W. |year=2005 |publisher=Pantheon Books |isbn=978-0-375-42231-7 |url=https://archive.org/details/damwaterpowerpol00simp}}</ref><ref>{{cite book |title=The Battle over Hetch Hetchy: America's Most Controversial Dam and the Birth of Modern Environmentalism |last=Righter |first=Robert W. |year=2005 |publisher=Oxford University Press |isbn=978-0-19-531309-3 |url=https://archive.org/details/battleoverhetchh00righ}}</ref>

Between 1912 and 1918, Congress debated three times to protect Lake Tahoe in a national park. None of these efforts succeeded, and after [[World War II]], towns such as [[South Lake Tahoe, California|South Lake Tahoe]] grew around the shores of the lake. By 1980, the permanent population of the Lake Tahoe area grew to 50,000, while the summer population grew to 90,000.<ref>{{cite web |title=Stream and Ground-Water Monitoring Program, Lake Tahoe Basin, Nevada and California |url=http://pubs.usgs.gov/fs/FS-100-97/ |publisher=USGS |access-date=May 31, 2010 |archive-date=May 30, 2010 |archive-url=https://web.archive.org/web/20100530064146/http://pubs.usgs.gov/fs/FS-100-97/ |url-status=live }}</ref> The development around Lake Tahoe affected the clarity of the lake water. In order to preserve the lake's clarity, construction in the Tahoe basin is currently regulated by the [[Tahoe Regional Planning Agency]].<ref>{{cite web |url=http://www.trpa.org/default.aspx?tabindex=1&tabid=40 |archive-url=https://web.archive.org/web/20110716131956/http://www.trpa.org/default.aspx?tabindex=1&tabid=40 |archive-date=July 16, 2011 |title=Construction Monitoring |publisher=Tahoe Regional Planning Agency |url-status=dead}}</ref>

As the 20th century progressed, more of the Sierra became available for recreation; other forms of economic activity decreased. The [[John Muir Trail]], a trail that followed the Sierra crest from Yosemite Valley to [[Mount Whitney]], was funded in 1915 and finished in 1938.<ref>{{cite journal |last=Starr |first=Walter A. |date=November 1947 |title=Trails |journal=Sierra Club Bulletin |volume=32 |issue=10}}</ref> [[Kings Canyon National Park]] was formed in 1940 to protect the deep canyon of the [[Kings River (California)|Kings River]].

In the 1920s, automobile clubs and nearby towns started to lobby for trans-Sierra highways over [[Piute Pass]]<ref name=usfsRoad>{{cite web |url=https://www.fs.usda.gov/Internet/FSE_DOCUMENTS/fseprd499744.pdf |title=The High Sierra Piute Highway |first=Steve |last=Marsh |publisher=US Forest Service |year=2015 |access-date=December 31, 2020 |archive-date=August 15, 2021 |archive-url=https://web.archive.org/web/20210815210623/https://www.fs.usda.gov/Internet/FSE_DOCUMENTS/fseprd499744.pdf |url-status=live }}</ref> (which would have closed the gap in [[California State Route 168|SR 168]]) and other locations. However, by end of the 1920s, the Forest Service and the Sierra Club decided that roadless wilderness in the Sierra was valuable, and fought the proposal. The Piute Pass proposal faded out by the early 1930s, with the Forest Service proposing a route over [[Minaret Summit]] in 1933.<ref name=usfsRoad/> The Minaret Summit route was lobbied against by California's Governor [[Ronald Reagan]] in 1972. The expansion of the [[John Muir Wilderness|John Muir]] and [[Ansel Adams Wilderness]]es in the 1980s sealed off the Minaret Summit route.<ref name=usfsRoad/>

A trans-Sierra route between [[Porterville, California|Porterville]] and [[Lone Pine, California|Lone Pine]] was proposed by local businessmen in 1923.<ref>{{cite news |newspaper=Los Angeles Times |title=Trail Over Mountains Supported |date=June 15, 1923 |page=II10}}</ref> Eventually, a circuitous route across the Sierra was built across [[Sherman Pass (California)|Sherman Pass]] by 1976.<ref>{{cite news |newspaper=The Fresno Bee |title=See It All in the Sierra |date=October 24, 1976}}</ref>

By 1964, the [[Wilderness Act]] protected portions of the Sierra as primitive areas where humans are simply temporary visitors. Gradually, 20 [[U.S. Wilderness Areas|wilderness areas]] were established to protect scenic [[backcountry]] of the Sierra. These wilderness areas include the [[John Muir Wilderness]] (protecting the eastern slope of the Sierra and the area between Yosemite and Kings Canyon Parks), and wilderness within each of the National Parks.

The Sierra Nevada still faces a number of issues that threaten its conservation. Logging occurs on both private and public lands, including controversial clearcut methods and thinning logging on private and public lands.<ref name=":0">{{Cite web |title=Forest Issues - CSERC |url=http://www.cserc.org/local-issues/forests/ |website=CSERC |date=December 16, 2014 |access-date=January 28, 2016 |language=en-US |archive-date=January 21, 2016 |archive-url=https://web.archive.org/web/20160121020027/http://www.cserc.org/local-issues/forests/ |url-status=live }}</ref> Grazing occurs on private lands as well as on National Forest lands, which include Wilderness areas. Overgrazing can alter hydrologic processes and vegetation composition, remove vegetation that serves as food and habitat for native species, and contribute to sedimentation and pollution in waterways.<ref>{{Cite web |title=2014 Grazing Report Released by CSERC - CSERC |url=http://www.cserc.org/news/2014-grazing-report-released-cserc/ |website=CSERC |access-date=January 28, 2016 |language=en-US |archive-date=February 2, 2016 |archive-url=https://web.archive.org/web/20160202145658/http://www.cserc.org/news/2014-grazing-report-released-cserc/ |url-status=dead}}</ref> A recent increase in large wildfires like the Rim Fire in Yosemite National Park and the Stanislaus National Forest and the King Fire on the Eldorado National Forest, has prompted concerns.<ref name=":0" /> A 2015 study indicated that the increase in fire risk in California may be attributable to [[anthropogenic global warming|human-induced climate change]].<ref>{{Cite journal |last1=Yoon |first1=Jin-Ho |last2=Wang |first2=S.-Y. Simon |last3=Gillies |first3=Robert R. |last4=Hipps |first4=Lawrence |last5=Kravitz |first5=Ben |last6=Rasch |first6=Philip J. |date=2015 |title=Extreme Fire Season in California: A Glimpse Into the Future? |url=https://www.researchgate.net/publication/283425168 |journal=Bulletin of the American Meteorological Society |volume=96 |issue=11 |doi=10.1175/BAMS-D-15-00114.1 |issn=1520-0477 |pages=S5–S9 |bibcode=2015BAMS...96S...5Y |osti=1240234 |doi-access=free |access-date=September 26, 2016 |archive-date=February 1, 2016 |archive-url=https://web.archive.org/web/20160201194439/https://www.researchgate.net/publication/283425168_EXTREME_FIRE_SEASON_IN_CALIFORNIA_A_GLIMPSE_INTO_THE_FUTURE |url-status=live }}</ref> A study looking back over 8,000 years found that warmer climate periods experienced severe droughts and more stand-replacing fires and concluded that as climate is such a powerful influence on wildfires, trying to recreate presettlement forest structure may be difficult in a warmer future.<ref>{{Cite journal |last1=Pierce |first1=Jennifer L. |last2=Meyer |first2=Grant A. |last3=Timothy Jull |first3=A. J. |date=November 4, 2004 |title=Fire-induced erosion and millennial-scale climate change in northern ponderosa pine forests |journal=Nature |language=en |volume=432 |issue=7013 |pages=87–90 |doi=10.1038/nature03058 |issn=0028-0836 |pmid=15525985 |bibcode=2004Natur.432...87P |s2cid=1452537}}</ref>