Editing Dutch elm disease (section)

===North America===
[[File:Dutch Elm.jpg|left|thumb|upright|Arborist removing infected elm in [[Saint Paul, Minnesota]]]]
DED was first reported in the [[United States]] in 1928, with the beetles believed to have arrived in a shipment of logs from the Netherlands destined for use as [[Wood veneer|veneer]] in the [[Ohio]] [[furniture]] industry. Quarantine and sanitation procedures held most cases within {{cvt|150|mi}} of metropolitan [[New York City]] until 1941 when war demands began to curtail them.<ref>[[Life (magazine)|''Life'']], 11 September 1944, p. 58</ref> The disease spread from [[New England]] westward and southward, almost completely destroying the famous elms in the "Elm City" of [[New Haven, Connecticut]], reaching the [[Detroit, Michigan|Detroit]] area in 1950,<ref>{{cite news |first=Vivian |last=Baulch |title=How Detroit lost its stately elms |newspaper=Detroit News |date=20 December 2001 |url=http://blogs.detroitnews.com/history/2001/12/20/how-detroit-lost-its-stately-elms-8/}}</ref> the [[Chicago, Illinois|Chicago]] area by 1960, and [[Minneapolis, Minnesota|Minneapolis]] by 1970. Of the estimated 77 million elms in North America in 1930, over 75% had been lost by 1989.<ref>New York Times, 5 December 1989, nytimes.com nytimes.com/1989/12/05/science/new-varieties-of-elm-raise-hope-of-rebirth-for-davastated-tree.html?sec=health&spon=</ref>
[[File:Defense.gov photo essay 060911-D-7203T-018.jpg|thumb|right|200px|Rows of American elm trees south of the [[Lincoln Memorial Reflecting Pool]] on the National Mall in Washington, D.C. (November 11, 2006)]]

The disease first appeared on the planted rows of [[Ulmus americana|American elm trees (''Ulmus americana'')]] on the [[National Mall#American elm trees|National Mall]] in [[Washington, D.C.]], during the 1950s and reached a peak in the 1970s. The United States [[National Park Service]] (NPS) used a number of methods to control the epidemic, including [[sanitation]], [[pruning]], injecting trees with [[fungicide]] and replanting with DED-resistant American elm cultivars (see [[Ulmus americana#Cultivars|''Ulmus americana'' cultivars]]). The NPS combated the disease's local insect [[Vector (epidemiology)|vector]], the smaller European elm bark beetle (''Scolytus multistriatus''), by trapping and by spraying with [[insecticide]]s. As a result, the population of American elms planted on the Mall and its surrounding areas has remained intact for more than 80 years.<ref>{{cite book|last=Sherald |first=James L |url=http://www.nps.gov/nationalmallplan/Documents/Studies/ElmsoftheMonuCore_HistandMgmtPlan_122009.pdf |title=Elms for the Monumental Core: History and Management Plan |id=Natural Resource Report NPS/NCR/NRR--2009/001 |place=Washington, D.C. |publisher=Center for Urban Ecology, National Capital Region, [[National Park Service]] |date=December 2009 |access-date=2010-10-14|archive-url=https://web.archive.org/web/20101129074707/http://www.nps.gov/nationalmallplan/Documents/Studies/ElmsoftheMonuCore_HistandMgmtPlan_122009.pdf|archive-date=2010-11-29}}</ref>

DED reached eastern Canada during World War II, and spread to [[Ontario]] in 1967, [[Manitoba]] in 1975 and [[Saskatchewan]] in 1981. In [[Toronto]], 80% of the elm trees have been lost to Dutch elm disease; many more fell victim in [[Ottawa]], [[Montreal]] and other cities during the 1970s and 1980s. [[Quebec City]] still has about 21,000 elms, thanks to a prevention program initiated in 1981.<ref>{{cite journal |first=Serge |last=Beaucher |title=Québec, terre des ormes |journal=Contact |volume=28 |issue=1 |date=Autumn 2009 |language=fr |url=http://www.contact.ulaval.ca/articles/quebec-terre-des-ormes-1361.html |publisher=Laval University}}</ref> [[Alberta]] and [[British Columbia]] are the only provinces that are currently free of Dutch elm disease, although, in an isolated case, an elm tree in [[Wainwright, Alberta]], was found diseased in June 1998 and was immediately destroyed.<ref>CFIA annual pest survey report. 1999 Summary of Plant Quarantine Pest and Disease Situations in Canada (report available upon demand at the Canadian Food Inspection Agency: http://publications.gc.ca/site/eng/9.831610/publication.html)</ref> The presence of DED was monitored in this area during subsequent years but was not seen again. Today, [[Alberta]] has the largest number of elms unaffected by Dutch elm disease in the world.<ref>{{cite web|url=http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/prm1043?opendocument|title=Dutch Elm Disease|publisher=Alberta Agriculture and Rural Development|access-date=14 December 2014|archive-date=21 May 2018|archive-url=https://web.archive.org/web/20180521191427/http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/prm1043?opendocument|url-status=dead}}</ref>

The provinces of Alberta, Manitoba, and [[Saskatchewan]] all prohibit the pruning of elm trees during the middle of the year (taking effect in April, and lasting through the end of September, July, and August respectively), which they deem to be the most active time of year for bark beetles.<ref>{{Cite web|url=https://www.cbc.ca/news/canada/manitoba/trees-winnipeg-hydro-ban-dutch-elm-1.4223733|title=Hydro contractors snubbing Winnipeg elm-pruning ban, group suspects|date=26 July 2017|website=CBC News|access-date=26 July 2019}}</ref><ref>{{Cite web|url=https://www.albertafarmexpress.ca/2018/04/11/elm-pruning-ban-now-in-place/|title=Elm pruning ban now in place|last1=Agriculture|first1=Alberta|last2=Forestry|date=2018-04-11|website=Alberta Farmer Express|language=en|access-date=2019-07-26}}</ref><ref name="regina.ctvnews.ca">{{Cite web|url=https://regina.ctvnews.ca/pruning-ban-on-elm-trees-starts-april-1-1.4350575|title=Pruning ban on elm trees starts April 1|website= CTV News Regina| date=25 March 2019 |access-date=2019-07-26}}</ref> It is also illegal to use, store, sell, or transport elm firewood.<ref name="regina.ctvnews.ca"/><ref>{{Cite web|url=http://www.sourisplaindealer.ca/news/majestic-elms-marked-for-removal-1.21564891|title=Majestic Elms marked for removal|last=Semeschuk|first=Darci|website=Souris Plaindealer|access-date=2019-07-26}}</ref><ref>{{Cite web|url=https://www.albertafarmexpress.ca/2016/11/14/elm-pruning-ban-over-until-march/|title=Elm pruning ban over until March|last=Release|first=Stopded|date=2016-11-14|website=Alberta Farmer Express|language=en|access-date=2019-07-26}}</ref>

The largest surviving urban forest of elm trees in North America is believed to be in the city of [[Winnipeg]], where close to 200,000 elms remain.<ref>{{Cite web |title=Winnipeg is home to the largest Urban Elm Forest in North America - Winnipeg {{!}} Globalnews.ca |url=https://globalnews.ca/news/2254543/winnipeg-is-home-to-the-largest-urban-elm-forest-in-north-america/ |access-date=2022-08-09 |website=Global News |language=en-US}}</ref> The city spends $3 million annually to aggressively combat the disease using [[Dursban|Dursban Turf]] and the Dutch Trig vaccine.<ref>{{cite web|title=Elm Bark Beetle Control Program |year=2009 |publisher=City of Winnipeg |url=http://www.winnipeg.ca/cms/bugline/news_releases/pdfs/2009/Elm%20Bark%20Beetle%20Program%20Commences%20August%207%202009.pdf }}{{dead link|date=June 2017 |bot=InternetArchiveBot |fix-attempted=yes }}</ref><ref name=Rumbolt09>{{cite web |first=Colin |last=Rumbolt |title=Dutch elm vaccine tested in Winnipeg |date=17 November 2009 |work=the Manitoban |url=http://www.themanitoban.com/2009/11/dutch-elm-vaccine-tested-in-winnipeg/530/}}</ref>