Editing Hypericum calycinum

{{Short description|Species of flowering plant in the St John's wort family Hypericaceae}}
{{Speciesbox
|image = Hypericum calycinum - Bauer.jpg
|image_caption = [[Ferdinand Bauer|Bauer]]'s [[Botanical illustration|Illustration]] from [[John Sibthorp|Sibthorp]]'s ''[[Flora Graeca]]''
|genus = Hypericum
|parent = Hypericum sect. Ascyreia
|species = calycinum
|authority = [[Carl Linnaeus|L.]]<ref name="linnaeus">Linnaeus, C. von (1767), ''Mantissa Plantarum'' 1: 106  [tax. nov.] Type: "Habitat in America septentrionali?"</ref><ref name=apni>{{cite web|url=https://biodiversity.org.au/nsl/services/rest/name/apni/81430/api/apni-format|title=''Hypericum calycinum''|work=Australian Plant Name Index (APNI)|publisher=Australian National Herbarium|access-date=2008-12-18}}</ref>
}}
[[File:Hypericum Calycinum photos.jpg|thumb|Taken outside the Mukilteo Washington Library in July 2022]]

'''''Hypericum calycinum''''' is a species of prostrate or low-growing [[shrub]] in the [[flowering plant]] family [[Hypericaceae]]. It is native to the [[Strandzha|Strandzha Mountains]] along the Bulgarian and Turkish Black Sea coast. Widely cultivated for its large yellow flowers, its names as a [[garden plant]] include '''rose-of-Sharon''' in [[Great Britain|Britain]]<ref name=BSBI07>{{BSBI 2007 |access-date=2014-10-17}}</ref> and [[Australia]], and '''Aaron's beard''', '''great St-John's wort''', '''creeping St. John's wort'''<ref name=mobot>[http://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?kempercode=a520 Hypericum calycinum. (n.d.). Retrieved April 9, 2018, from]</ref> and '''Jerusalem star'''.

==Description==
''Hypericum calycinum'' is a low, creeping, [[evergreen]] woody shrub (classified as a subshrub or shrublet<ref name=mobot/>) to about 1 m tall and 1–2 m wide but often smaller. The green, ovate leaves grow in opposite pairs. Usually 4 inches long, the undersides of the leaves are net-veined. In the sun, the leaves are a vibrant green color, and in shade, the leaves are a lighter yellow-green.<ref name=mobot/> The underside of the leaves is a blue-green color and in the fall, the leaves take on a purple color.<ref name=ncsu>[https://plants.ces.ncsu.edu/plants/all/hypericum-calycinum/ Hypericum calycinum. (n.d.). Retrieved April 9, 2018, from]</ref>

The flowers are 3–5&nbsp;cm in diameter, a rich yellow, with five petals and numerous yellow [[stamen]]s. Its flowers can be described as "rose-like" and tend to be single or in units of two or three,<ref name=mobot/> flowering in June to September.<ref>Parnell, J. and Curtis, T. 2012. ''Webb's An Irish Flora.'' Cork University Press{{ISBN|978-185918-4783}}</ref>

''Hypericum calycinum'' is indigenous to southeast [[Europe]] and southwest [[Asia]]. It is a popular, semi-[[evergreen]] garden shrub with many named [[cultivar]]s and [[hybrid (biology)|hybrid]]s derived from it.

Although the genus is generally not affected by [[Rust (fungus)|rust fungi]], it can appear on ''H. calycinum'' (and another cultivated plant, [[Hypericum × inodorum|''Hypericum'' × ''inodorum'']] 'Elstead').<ref name=broddle2007>{{cite magazine |last=Broddle |first=Petra |date=20 September 2007 |title=Hypericum |pages=22–23 |magazine=Horticulture Week |location=Teddington |id={{ProQuest|225418901}} }}</ref>

==Usage==
Various species of the genus ''Hypericum'' have been used since ancient times as [[Herbalism|herbal remedies]].<ref name=ozturk1996>Öztürk, Y., Aydin, S., Beis, R., Başer, K. H. C., & Berberoĝlu, H. (1996). Effects of Hypericum perforatum L. and Hypericum calycinum L. extracts on the central nervous system in mice. ''Phytomedicine'', ''3''(2), 139–146.</ref> This species has been used traditionally to reduce [[Spasm|muscle spasms]] and for the treatment of [[asthma]].<ref name=mat2013>Mat, A. (2013). An overview on Hypericum species of Turkey. ''Journal of Pharmacognosy and Phytotherapy'', ''5''(3), 38–46.</ref>

''Hypericum calycinum'' is an economically valuable plant in [[North America]], commonly used for [[Ornamental plant|ornamental]] reasons and [[landscaping]].<ref name=hinz2017>{{cite journal |last1=Hinz |first1=Hariet L. |last2=Schwarzländer |first2=Mark |last3=Gassmann |first3=André |last4=Bourchier |first4=Robert S. |title=Successes We May Not Have Had: A Retrospective Analysis of Selected Weed Biological Control Agents in the United States |journal=Invasive Plant Science and Management |date=20 January 2017 |volume=7 |issue=4 |pages=565–579 |doi=10.1614/IPSM-D-13-00095.1|s2cid=83493514 |doi-access=free }}</ref>

Under ideal growing conditions, from full sun to partial shade and well-drained [[Soil pH|acidic soil]], this species can grow rapidly.<ref name=ncsu/> Although resilient in many soil types, this species grows best in sandy or [[loam]]y soils. This shrub grows through [[underground stem]]s and is typically grown as [[Groundcover|ground cover]] or to stabilize soil on hills and requires low maintenance. It does have the potential to become [[Invasive species|invasive]], as reported in some areas of [[California]],<ref name=mobot/> due to its ability to grow rapidly by [[stolon]]s. While generally easy to take care of, this species is suggested to be cut down each spring.<ref name=broddle2007/>

According to the [[United States Department of Agriculture|USDA]], this species is used as nursery stock product.<ref name=usda>{{Cite PLANTS |symbol=HYCA10 |taxon=Hypericum calycinum |access-date=April 11, 2018 }}</ref>

It is visited by the [[honeybees]] for its [[pollen]]. <ref>{{cite web | url=http://florabeilles.org/serie/hypericum-calycinum_apis-mellifera | title=Hypericum calycinum & Apis mellifera | date=28 July 2013 }}</ref>

[[Image:Hypericum calycinum Tasmania.jpg|thumb|right|''Hypericum calycinum'']]

==Etymology==
In North America the name Rose of Sharon is applied to a species in a different order, ''[[Hibiscus syriacus]].''

The common name of St. John's wort, which is used to describe plants of the entire genus,<ref name=mat2013 /> arose from the old tradition of ''Hypericum'' plants being burned on the eve of St. John's Day, to stave off evil spirits. The species name, ''calycinum'', comes from the flower's prominent calyx, the [[Whorl (botany)|whorl]] of the [[sepal]]s.<ref name=mobot/>

==Research==
This species is capable of producing the same medicinally active components as ''H. perforatum'' ([[hyperforin]] etc.), though in different ratios, with [[adhyperforin]] predominating, and a low level of hyperforin present.<ref name="calcynum hyperforin">{{cite journal|last1=Klingauf|first1=P|last2=Beuerle|first2=T|last3=Mellenthin|first3=A|last4=El-Moghazy|first4=SA|last5=Boubakir|first5=Z|last6=Beerhues|first6=L|date=January 2005|title=Biosynthesis of the hyperforin skeleton in Hypericum calycinum cell cultures.|journal=Phytochemistry|volume=66|issue=2|pages=139–45|doi=10.1016/j.phytochem.2004.11.003|pmid=15652570|bibcode=2005PChem..66..139K}}</ref>

Research has shown that the UV pigments of the ''Hypericum calycinum'' flower stave off predators such as [[mite]]s and [[aphid]]s. One type of DIP (dearomatized isoprenylated phloroglucinols), a category of pigments alongside [[flavonoid]]s, was found to be toxic to a caterpillar as well. A large quantity of DIPs were found in the male and female reproductive organs, which furthers emphasizes the use of DIPs as a defense mechanism. These pigments also serve a dual function to attract pollinators, as they are visible to insects and not humans.<ref>Gronquist, M., Bezzerides, A., Attygalle, A., Meinwald, J., Eisner, M., & Eisner, T. (2001). Attractive and defensive functions of the ultraviolet pigments of a flower (Hypericum calycinum). ''Proceedings of the National Academy of Sciences'', ''98''(24), 13745-13750.</ref>

Recent research on mice has shown that the alcoholic extracts from ''Hypericum calycinum'' have antidepressant effects and are comparably as effective as antidepressant drugs, such as [[desipramine]] and [[trimipramine]]. Unlike the rest of the genus, ''H. calycinum'' does not have [[hypericin]], which causes [[Photosensitizer|photosensitization]], which causes the side effects of flush, fatigue, and [[pruritus]] when used in drugs. These extracts have the potential to be a remedy for depression without these side effects common in current antidepressants. However, more research is required.<ref name=ozturk1996 />

==References==
{{Commons|Hypericum_calycinum|Hypericum calycinum}}
{{Reflist}}

{{Taxonbar|from=Q159330}}

[[Category:Hypericum|calycinum]]
[[Category:Groundcovers]]
[[Category:Flora of Europe]]
[[Category:Flora of Asia]]