Editing Elm (section)

====Cautions regarding novel cultivars====
Elms take many decades to grow to maturity, and as the introduction of these disease-resistant cultivars is relatively recent, their long-term performance and ultimate size and form cannot be predicted with certainty. The [[National Elm Trial]] in North America, begun in 2005, is a nationwide trial to assess strengths and weaknesses of the 19 leading cultivars raised in the US over a 10-year period; European cultivars have been excluded.<ref>(1) {{cite web |year=2018 |title=National Elm Trial |url=http://bspm.agsci.colostate.edu/national-elm-trial/ |work=Bioagricultural Sciences & Pest Management |publisher=[[Colorado State University College of Agricultural Sciences]]: [[Colorado State University College of Agricultural Sciences#Academic Departments|Department of Agricultural Biology]] |location=[[Fort Collins, Colorado]] |access-date=8 February 2021 |archive-date=30 March 2018 |archive-url=https://web.archive.org/web/20180330152322/http://bspm.agsci.colostate.edu/national-elm-trial/ |url-status=dead }}.<br />(2) {{cite journal |last1=Griffin |first1=Jason J. |last2=Jacobi, E. |first2=William R. |last3=McPherson |first3=Gregory |last4=Sadof |first4=Clifford S. |last5=McKenna |first5=James R. |last6=Gleason |first6=Mark L. |last7=Gauthier |first7=Nicole Ward |last8=Potter |first8=Daniel A. |last9=Smitley |first9=David R. |last10=Adams |first10=Gerard C. |last11=Gould |first11=Ann Brooks |display-authors=4 |year=2017 |title=Ten-Year Performance of the United States National Elm Trial |url=https://webdoc.agsci.colostate.edu/bspm/NationalElmTrial/AUF2017.pdf |journal=Arboriculture & Urban Forestry |publisher=[[International Society of Arboriculture]] |volume=43 |pages=107–120 |doi=10.17660/ActaHortic.2018.1191.5 |issn=0567-7572 |oclc=7347020445 |access-date=February 7, 2021 |first12=Christian R. |last12=Cash |first13=James A. |last13=Walla |first14=Mark C. |last14=Starrett |first15=Gary |last15=Chastagner |first16=Jeff L. |last16=Sibley |first17=Vera A. |last17=Krischik |first18=Adam F. |last18=Newby |number=3 }}</ref> Meanwhile, in Europe, American and European cultivars are being assessed in field trials started in 2000 by the UK charity [[Butterfly Conservation]].<ref name="Brookes">Brookes, A. H. (2013). ''Disease-resistant elm cultivars, Butterfly Conservation trials report, 2nd revision, 2013.'' Butterfly Conservation, Hants & IoW Branch, England. {{cite web |title=Archived copy |url=http://www.hantsiow-butterflies.org.uk/conservation/2013%20Elm%20Report%20Sept%202013.pdf |url-status=dead |archive-url=https://web.archive.org/web/20140529181302/http://hantsiow-butterflies.org.uk/conservation/2013%20Elm%20Report%20Sept%202013.pdf |archive-date=29 May 2014 |access-date=2014-01-30 |df=dmy-all}}</ref>