Editing Ydre Municipality (section)

==Climate and vegetation==
[[File:Naturreservat Torpon.jpg|thumb|left|View from Torpön naturresevat in the southern tip of Torpön, April 2019.]]
{{see also|Sarmatic mixed forests}}
Relative to other areas of southern Sweden Ydre stands out for its low precipitation and low humidity.<ref name=sodra2015>{{cite report |chapter=4. östra Götalands sprickdals- och eklandskap |date=2015 |title=Skogliga naturvärdesregioner för södra Sverige|trans-title=Forest biodiversity regions in southern Sweden  |url=http://skogscertifiering.se/wp-content/uploads/2017/10/Naturv%C3%A4rdesregioner_Rapport-S%C3%B6dra-Skogs%C3%A4garna.pdf |publisher=Södra |page=66 |language=sv }}</ref> The rainiest months of the years are September followed by July and August. Each of these months had a precipitation of c. 70&nbsp;mm. The driest months are February and March, with 35&nbsp;mm each.{{efn-ua|Precipitation is given for [[Norra Vi]] 1961–1990.<ref name=natprov/>}} The hottest months are July, Juni and August averaging 14–15&nbsp;°C. The coldest months are January and February with about -4&nbsp;°C.<ref name=natprov>{{cite report |date=2017 |title=Nätprovfiske i Sommen 2016 |url=http://www.diva-portal.org/smash/get/diva2:1205926/FULLTEXT01.pdf|language=sv |publisher=Länsstyrelsen Jönköping |series=Meddelande |access-date=April 19, 2019}}</ref>{{efn-ua|Temperatures are given for [[Malexander]] 1961–1990.<ref name=natprov/>}} The climate is expected to become warmer and drier in future.<ref name=natprov/>

The [[growing season]] around Sommen is of about 216 days with 2614 [[degree day]]s.<ref name=larsetal2005>{{cite journal |last1=Larsson |first1=S. |last2=Forseth |first2=T. |last3=Berglund |first3=I.|last4=Jensen |first4=A.J.|last5=Näslund |first5=I. |last6=Elliott |first6=J.M.|last7=Jonsson |first7=B.|date=2005 |title=Thermal adaptation of Arctic charr: experimental studiesof growth in eleven charr populations from Sweden, Norway and Britain |url=https://www.researchgate.net/publication/229589055 |journal=[[Freshwater Biology]] |volume=50 |issue= 2|pages=353–368 |doi=10.1111/j.1365-2427.2004.01326.x |access-date=June 10, 2019}}</ref> The vegetation in Ydre is mostly dominated by [[pinus sylvestris|pine]] and [[Picea abies|spruce]] forest. [[Temperate deciduous forest|Broad-leaf forest]] and [[agriculture in Sweden|open agricultural fields]] can also be found at some locations.<ref name=vattenorg>{{cite report |title=Sommen |url=https://www.vattenorganisationer.se/motalasodra/downloads/36/Forenklat_Sommenblad.pdf |publisher=vattenorganisationer.se |access-date=April 20, 2019 |language=sv }}</ref> In particular the southern shores of lake Sommen contain more lush vegetation and broad-leaf forest than the northern side, which has more cliffs and contiguous pine forests.<ref name=Hellgren1960>{{cite book |last1=Hellgren |first1=George |title=Ydre-Boken |date=1960 |location=Linköping |pages=86–91|chapter=Något om växtligheten i Ydre|editor-last=Filén|editor-first=Thure|language=sv}}</ref> The rare and endangered flower ''[[Anthericum liliago]]'' can be found along the lake's rocky shores.<ref name=sommennatsom>{{cite web |title=Om naturum |url=http://sommen-naturum.se/om%20sommen.html |website=sommen-naturum.se |publisher=Naturum Sommen |access-date=April 20, 2019|language=sv}}</ref><ref name=storsandliljaartdata>{{cite web |title=Anthericum liliago Stor sandlilja |url=http://artfakta.artdatabanken.se/taxon/61 |website=Artdatabanken |publisher=[[Swedish University of Agricultural Sciences]] |access-date=May 2, 2019|language=sv}}</ref> This is one of the northernmost locales where it grows.<ref name=storsandliljaartdata/>

In Torpön island grows Sweden's largest [[Ulmus glabra|wych elm]] and at [[Asby, Sweden|Asby]], a few kilometers from the southern shores grows Sweden's thickest [[Picea abies|spruce]].<ref>{{cite web |url=https://www.ydre.se/turism/segora/storatrad.4.548e62af1215e34a249800051857.html |title=Stora träd i Ydre |website=ydre.se |publisher=Ydre kommun |access-date=April 20, 2019 |language=sv}}</ref> The name [[Ydre]], which was formerly applied to most of the area around Sommen, is interpreted to mean "place of [[Taxus baccata|yews]]".<ref name=ortnamnlexiko2003-375>{{cite book |last1=Wahlberg |first1=Mats |title=Svensk ortnamnslexikon |date=2003 |publisher=Språk- och folkminnesinstitutet |location=Uppsala |isbn=91-7229-020-X |page=375 |url=https://www.sprakochfolkminnen.se/download/18.5850f85e15732ead0b325e/1529494467246/Svenskt%20ortnamnslexikon.pdf |access-date=April 30, 2019|language=sv}}</ref> One locality in particular appears to be further associated with yews. This is [[Idebo]] along Norra Vifjärden.<ref name=ortnamnlexiko2003-375/>{{efn-ua|Also, about 33 km east of Sommen there is a locality named [[Idhult]], probably also linked to yews.<ref name=ortnamnlexiko2003-375/>}}

Some plants usually associated to [[carbonate rock]] areas appears as rarities near Sommen, since there are no known carbonate rock [[outcrop]]s in the area. The plants are ''[[Vicia|Vicia pisiformis]]'' and the [[Orchidaceae|orchids]] ''[[Ophrys|Ophrys myoides]]'', ''[[Malaxis|Malaxis monophyllos]]'',  ''[[Herminium monorchis]]''.<ref name=Hellgren1960/>{{efn-ua|''[[Vicia|Vicia pisiformis]]'' can be found in carbonate-rich areas in [[Kolmården]] and [[Kinnekulle]], while the said orchids are best known in Sweden from calcium-rich fens in [[Gotland]] and [[Öland]].<ref name=Hellgren1960/>}}