Arctotheca calendula

{{short description|Species of plant}} {{speciesbox |name = ''Arctotheca calendula'' |image = Arctotheca calendula 2.JPG |genus = Arctotheca |species = calendula |authority = (L.) Levyns |synonyms_ref=<ref>[http://www.theplantlist.org/tpl1.1/record/gcc-44713 The Plant List ''Arctotheca calendula'' (L.) Levyns ]</ref> |synonyms={{collapsible list|bullets = true |title=Synonymy |''Alloiozonium arctotideum'' Kunze |''Arctotheca calendulacea'' (L.) K.Lewin |''Arctotheca calendulaceum'' K.Lewin |''Arctotis calendula'' L. |''Arctotis calendulacea'' L. |''Arctotis hypochondriaca'' Willd. |''Arctotis speciosa'' Salisb. |''Arctotis sulphurea'' Gaertn. |''Arctotis superba'' L. |''Arctotis tristis'' L. |''Cryptostemma calendula'' (L.) Druce |''Cryptostemma calendulaceum'' (L.) R.Br. |''Cryptostemma hypochondriacum'' R.Br. |''Cryptostemma runcinatum'' R.Br. |''Cryptostemma triste'' (L.) Domin |''Cynotis hypochondriaca'' Hoffmanns }}}}

'''''Arctotheca calendula''''' is a plant in the sunflower family commonly known as '''capeweed''',<ref>{{PLANTS|id=ARCA45|taxon=Arctotheca calendula|accessdate=8 January 2016}}</ref> '''plain treasureflower''',<ref name=BSBI07>{{BSBI 2007 |accessdate=2014-10-17 }}</ref> '''cape dandelion''', or '''cape marigold''' because it occurs in the Western Cape Province in South Africa.<ref>Levyns, Margaret Rutherford Bryan 1942. Journal of South African Botany 8(4): 284</ref><ref>{{Cite web|url=http://www.tropicos.org/Name/2717157|title=Tropicos | Name - ''Arctotheca calendula'' (L.) Levyns|website=www.tropicos.org|accessdate=October 1, 2019}}</ref> It has a wide distribution in coastal areas of South Africa, extending from Namaqualand to Cape Point and as far as KwaZulu-Natal.<ref name=pza>{{Cite web|url=http://pza.sanbi.org/arctotheca-calendula|title=''Arctotheca calendula'' | PlantZAfrica|website=pza.sanbi.org|accessdate=October 1, 2019}}</ref>

==Description== ''Arctotheca calendula'' is a squat perennial or annual herb which grows in rosettes and sends out stolons and can spread across the ground quickly. The leaves are covered with white woolly hairs, especially on their undersides. The leaves are lobed or deeply toothed, arranged in a basal rosette and distributed along the stem, are divided into a petiole and a leaf blade. The leaf blade is 5 to 25 centimeters long and 2 to 5 centimeters wide, with the uppermost almost simple and obovate; the lower ones are pinnately lobed to lyre-shaped. The upper surface of the leaf is finely hairy, cobweb-like, and the underside is densely covered with white, tomentose or woolly hairs.<ref name=pza/>

The name 'Actotheca' comes from Greek words 'arktos' meaning 'a bear', and 'theke', which translates to 'a capsule' (or a 'case'); referring to the heavily fuzzy fruits. The species name 'calendula' may refer to its resemblance to the European genus Calendula that means 'little calendar', which derives from the Greek word 'kalendae', meaning 'the first day of the month', and could refer to its long-flowering span.<ref name=pza/>

===Inflorescence=== thumb|Groundcover with flowers Hairy stems bear daisy-like flowers with small yellow petals that sometimes have a green or purple tint surrounded by white or yellow ray petals extending further out from the flower centers. The flower heads are located on leaf-axillary inflorescence stalks that are usually 15 to 20 (10 to 25) centimeters long. The hemispherical involucrum with a diameter of about 1.5 centimeters consists of several rows of bracts.

The flower heads have a diameter of about 5, 2.5 to 4, rarely up to 6 centimeters. There are fewer than 20 (6 to 13, rarely up to 17) ray florets in a flower head. The approximately 3 millimeter long achenes are pinkish-brown and covered with silky, woolly hairs. The flowering period in South Africa is in winter, spring to early summer and extends from July to November. In southern Europe, however, the flowering period is March to June.<ref name=pza/>

==Cultivation== It is cultivated as an attractive ornamental groundcover but has invasive potential when introduced to a new area. Growing best in full sun and hardy to moderate frost,<ref name=pza/> the plant can reproduce vegetatively or via seed. Seed-bearing plants are most likely to become weedy, taking hold most easily in bare or sparsely vegetated soil or disturbed areas.<ref>{{Cite web|url=http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=250066097|title=''Arctotheca calendula'' in Flora of North America @ efloras.org|website=www.efloras.org|accessdate=October 1, 2019}}</ref>

==Distribution == ''Arctotheca calendula'' is native to southern Africa in Lesotho and in the South African provinces of KwaZulu-Natal, Eastern Cape, Northern Cape and Western Cape, where it thrives in Namaqualand, the Karoo and as far as the Cape Peninsula, where it is found in coastal areas on ruderal sandy soils, along roadsides, on old farmland, and on disturbed sites.<ref name=pza/>

It is naturalized in California,<ref>[http://ucce.ucdavis.edu/datastore/detailreport.cfm?usernumber=7&surveynumber=182 California Invasive Plant Council, University of California @ Davis]</ref><ref>{{Cite web|url=https://www.calflora.org//cgi-bin/species_query.cgi?where-calrecnum=634|title=''Arctotheca calendula'' Calflora|website=www.calflora.org|accessdate=October 1, 2019}}</ref> Spain,<ref>[http://www.floravascular.com/index.php?spp=Arctotheca%20calendula Flora Vascular de Andalucía Occidental, ''Arctotheca calendula'' (L.) Levyns ] in Spanish</ref><ref>[http://floracatalana.es/A/arctotheca%20calendula Flora Catalana, ''Arctotheca calendula''] in Catalan with color photos</ref> Portugal, Italy,<ref>[http://luirig.altervista.org/flora/taxa/index1.php?scientific-name=arctotheca+calendula Altervista Flora Italiana, Arctoteca simile alla calendola, ''Arctotheca calendula'' (L.) Levyns] numerous photos</ref> Australia,<ref>{{Cite web|url=https://bie.ala.org.au/species/https://id.biodiversity.org.au/taxon/apni/51267241|title=''Arctotheca calendula''|website=Atlas of Living Australia|accessdate=October 1, 2019}}</ref><ref>[http://www.weeds.org.au/cgi-bin/weedident.cgi?tpl=plant.tpl&ibra=all&card=H70 Weeds Australia, Capeweed ''Arctotheca calendula''] {{dead link|date=December 2016|bot=medic}}{{cbignore|bot=medic}}</ref> New Zealand,<ref>[http://www.nzflora.info/factsheet/Weed/Arctotheca_calendula.html Flora of New Zealand ''Arctotheca calendula'' (L.) Levyns]</ref> and Chile,<ref>[https://www.chlorischile.cl/ARCOTECAWEB/arctotecamedina.htm ESPECIE INVASORA DE SUELOS ARENOSOS EN LA REGIÓN DE LA ARAUCANÍA (IX), CHILE Chloris chilense, Revista chilena de flora y vegetación. ''Arctotheca calendula''] in Spanish</ref> and considered a noxious weed in some of those places.

==References== {{Reflist}}

==External links== *[http://ucjeps.berkeley.edu/cgi-bin/get_JM_treatment.pl?609,695,696 Jepson Manual Treatment] *[http://plantnet.rbgsyd.nsw.gov.au/cgi-bin/NSWfl.pl?page=nswfl&lvl=sp&name=Arctotheca~calendula New South Wales Flora] *[http://www.cdfa.ca.gov/phpps/ipc/weedinfo/arctotheca.htm Capeweed at EncycloWeedia] *[http://www.cal-ipc.org/ip/management/ipcw/pages/detailreport.cfm@usernumber=7&surveynumber=182.php Invasive Plants of California's Wildlands] *[http://keyserver.lucidcentral.org/weeds/data/03030800-0b07-490a-8d04-0605030c0f01/media/Html/Arctotheca_calendula.htm Queensland Government Factsheet]

Category:Arctotideae Category:Flora of the Cape Provinces Category:Flora of the Free State (province) Category:Flora of KwaZulu-Natal Category:Flora of Lesotho Category:Botanical taxa named by Carl Linnaeus Category:Flora of South Africa Category:Garden plants of Southern Africa Category:Groundcovers