Editing Eucalyptus (section)

===North America===
;California
In the 1850s, ''Eucalyptus'' trees were introduced to [[California]] by Australians during the [[California Gold Rush]]. Much of California is similar in climate to parts of Australia. By the early 1900s, thousands of acres of eucalypts were planted with the encouragement of the state government. It was hoped that they would provide a renewable source of timber for construction, furniture making and [[railway sleeper]]s. It was soon found that for the latter purpose ''Eucalyptus'' was particularly unsuitable, as the ties made from ''Eucalyptus'' had a tendency to twist while drying, and the dried ties were so tough that it was nearly impossible to hammer [[Rail fastening system|rail spikes]] into them.<ref name="Santos" />

<blockquote>They went on to note that the promise of ''Eucalyptus'' in California was based on the old virgin forests of Australia. This was a mistake, as the young trees being harvested in California could not compare in quality to the centuries-old ''Eucalyptus'' timber of Australia. It reacted differently to harvest. The older trees didn't split or warp as the infant California crop did. There was a vast difference between the two, and this would doom the California ''Eucalyptus'' industry.<ref name="Santos">{{cite web |last1=Santos |first1=Robert L. |title=''The Eucalyptus of California - Seeds of good or seeds of evil?'' |url=https://library.csustan.edu/ld.php?content_id=55856157 |publisher=University Library - Stanislaus State |access-date=31 March 2021}}</ref></blockquote>

[[File:Howard-Ralston Eucalyptus Tree Rows.jpg|thumb|upright|The Howard-Ralston Eucalyptus Tree Rows, planted in [[Burlingame, California]], in the 1870s, are listed on the [[National Register of Historic Places]].]]
The species ''[[Eucalyptus camaldulensis|E. camaldulensis]], [[Eucalyptus tereticornis|E. tereticornis]],'' and ''[[Eucalyptus cladocalyx|E. cladocalyx]]'' are all present in California, but the blue gum ''[[Eucalyptus globulus|E. globulus]]'' makes up by far the largest population in the state.<ref>{{Cite web|url=https://books.google.com/books?id=EVIzzgEACAAJ|title=Growth of Eucalyptus in California Plantations|first=Woodbridge|last=Metcalf|date=Oct 1, 1924|publisher=University of California Print. Office|accessdate=Oct 1, 2022|via=Google Books}}</ref> One way in which the ''Eucalyptus'', mainly the blue gum ''[[Eucalyptus globulus|E. globulus]]'', proved valuable in California was in providing windbreaks for highways, orange groves, and farms in the mostly treeless [[Central Valley (California)|central part of the state]]. They are also admired as shade and ornamental trees in many cities and gardens.{{cn|date=June 2024}}

''Eucalyptus'' plantations in California have been criticised, because they compete with native plants and typically do not support native animals. ''Eucalyptus'' has historically been planted to replace California's [[Quercus agrifolia|coast live oak]] population, and the new ''Eucalyptus'' is not as hospitable to native flora and fauna as the oaks. In appropriately foggy conditions on the California Coast, ''Eucalyptus'' can spread at a rapid rate. The absence of natural inhibitors such as the [[koala]] or pathogens native to Australia have aided in the spread of California ''Eucalyptus'' trees. This is not as big of an issue further inland, but on the coast invasive eucalypts can disrupt native ecosystems. ''Eucalyptus'' may have adverse effects on local streams due to their chemical composition, and their dominance threatens species that rely on native trees. Nevertheless, some native species have been known to adapt to the ''Eucalyptus'' trees. Notable examples are [[heron]]s, [[great horned owl]], and the [[monarch butterfly]] using ''Eucalyptus'' groves as habitat. Despite these successes, eucalypts generally has a net negative impact on the overall balance of the native ecosystem.<ref name=":1" />

A heavy concern regarding Eucalypts in California is their status as a fire hazard.<ref>{{Cite news |date=2006 |title=Fire Management Newsletter: Eucalyptus: A Complex Challenge |url=https://home.nps.gov/pore/learn/nature/upload/firemanagement_fireeducation_newsletter_eucalyptus.pdf |access-date=Oct 29, 2024 |work=U.S. National Park Service}}</ref> ''Eucalyptus'' trees were a catalyst for the spread of the [[1923 Berkeley, California fire|1923 fire]] in Berkeley, which destroyed 568 homes.<ref name=":1">{{Cite web|last=Liza|first=Gross|date=June 12, 2013|title=Eucalyptus: California Icon, Fire Hazard and Invasive Species|url=https://www.kqed.org/science/4209/eucalyptus-california-icon-fire-hazard-and-invasive-species#:~:text=The%20California%20Invasive%20Plant%20Council,need%20certain%20conditions%20to%20thrive.&text=Once%20established%2C%20the%20trees%20can,mineralization%20rates%20and%20soil%20chemistry.|website=KQED}}</ref> The 1991 [[Oakland firestorm of 1991|Oakland Hills firestorm]], which caused US$1.5 billion in damage, destroyed almost 3,000 homes, and killed 25 people, was partly fueled by large numbers of eucalypts close to the houses.<ref>{{cite web |last=Williams |first=Ted |title=America's Largest Weed |publisher=Audubon Magazine |date=January 2002 |url=http://magazine.audubon.org/incite/incite0201.html |url-status=dead |archive-url=https://web.archive.org/web/20060708221528/http://magazine.audubon.org/incite/incite0201.html |archive-date=2006-07-08 }}</ref>

Despite these issues, there are calls to preserve the ''Eucalyptus'' plants in California. Advocates for the tree claim its fire risk has been overstated. Some even claim that the ''Eucalyptus's'' absorption of moisture makes it a barrier against fire. These experts believe that the herbicides used to remove the ''Eucalyptus'' would negatively impact the ecosystem, and the loss of the trees would release carbon into the atmosphere unnecessarily. There is also an aesthetic argument for keeping the ''Eucalyptus''; the trees are viewed by many as an attractive and iconic part of the California landscape. Many say that although the tree is not native, it has been in California long enough to become an essential part of the ecosystem and therefore should not be attacked as invasive. These arguments have caused experts and citizens in California, especially in the [[San Francisco Bay Area]], to debate the merits of ''Eucalyptus'' removal versus preservation. However, the general consensus remains that some areas urgently require ''Eucalyptus'' management to stave off potential fire hazards.<ref name=":0">{{Cite web|last=Emma|first=Marris|date=November 30, 2016|title=The Great Eucalyptus Debate|url=https://www.theatlantic.com/science/archive/2016/11/the-great-eucalyptus-debate/509069/|website=The Atlantic}}</ref>

Efforts to remove some of California's ''Eucalyptus'' trees have been met with a mixed reaction from the public, and there have been protests against removal.<ref name=":0" /> Removing ''Eucalyptus'' trees can be expensive and often requires machinery or the use of herbicides. The trees struggle to reproduce on their own outside of the foggy regions of Coastal California, and therefore some inland ''Eucalyptus'' forests are predicted to die out naturally.<ref>{{Cite web|last=Daniel|first=Potter|date=February 1, 2018|title=Eucalyptus: How California's Most Hated Tree Took Root|url=https://www.kqed.org/news/11644927/eucalyptus-how-californias-most-hated-tree-took-root-2|website=KQED}}</ref> In some parts of California, eucalypt plantations are being removed and native trees and plants restored. Individuals have also illegally destroyed some trees and are suspected of introducing insect pests from Australia which attack the trees.<ref name="Henter2005">{{cite web |title=Tree Wars: The Secret Life of Eucalyptus |first=Heather |last=Henter |date=January 2005 |publisher=University of California, San Diego |work=Alumni |url=http://alumni.ucsd.edu/magazine/vol2no1/features/wars.htm|access-date=2013-11-23 |archive-url=https://web.archive.org/web/20090317055602/http://alumni.ucsd.edu/magazine/vol2no1/features/wars.htm |archive-date=2009-03-17 |url-status=dead}}</ref>

Certain ''Eucalyptus'' species may also be grown for ornament in warmer parts of the Pacific Northwest—western [[Washington (state)|Washington]], western [[Oregon]] and southwestern [[British Columbia]].{{cn|date=June 2024}}