Ambrosia confertiflora

{{short description|Species of flowering plant}}

{{speciesbox

|genus = Ambrosia

|species = confertiflora

|image = Ambrosia confertiflora 1448 Flowering branch Richard-Spellenberg.jpg

|status = {{TNCStatus}}

|status_system = TNC

|authority = DC.

|synonyms_ref = [http://www.theplantlist.org/tpl1.1/record/gcc-42004 The Plant List Ambrosia confertiflora DC. ]

|synonyms = {{collapsible list|bullets = true

|title=Synonymy

|Ambrosia caudata (Rydb.) Shinners

|Ambrosia fruticosa DC. 1836 not Medik. 1775

|Ambrosia simulans Shinners

|Franseria caudata Rydb.

|Franseria confertiflora (DC.) Rydb.

|Franseria hispidissima Rydb.

|Franseria incana Rydb.

|Franseria pringlei Rydb.

|Franseria strigulosa Rydb.

|Franseria tenuifolia Harv. & A.Gray

|Gaertneria tenuifolia (Harv. & A.Gray) Kuntze

|Gaertneria tenuifolia Harv. & A.Gray

|Xanthidium tenuifolium (Harv. & A.Gray) Delpino

|}}}}

Ambrosia confertiflora is a North American species of ragweed known by the common name weakleaf bur ragweed.[http://www.calflora.org/cgi-bin/species_query.cgi?where-calrecnum=294 Calflora taxon report, University of California, Ambrosia confertiflora DC. weak leaved burweed, weakleaf burr ragweed ]

Description

Ambrosia confertiflorais a perennial herb reaching heights between 30 centimeters and nearly two meters with bristly, fuzzy green to brown erect stems. The multilobed fuzzy leaves have blades which can be nearly 16 centimeters long and are borne on petioles with lobed, winglike appendages. As in other ragweeds, the inflorescence has staminate (male) and pistillate (female) flower heads. The pistillate heads yield one or two fruits which are burrs up to half a centimeter long and covered in short spines.[http://ucjeps.berkeley.edu/cgi-bin/get_JM_treatment.pl?609,648,654 Jepson Manual Treatment][http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=250066047 Flora of North America Vol. 21 Page 18 Ambrosia confertiflora de Candolle in A. P. de Candolle and A. L. P. P. de Candolle, Prodr. 5: 526. 1836.]

Distribution and habitat

Ambrosia confertiflora is native to much of northern Mexico (from Sonora to Tamaulipas) and the southwestern United States from California east as far as Kansas, Oklahoma, and central Texas.[http://bonap.net/MapGallery/County/Ambrosia%20confertiflora.png Biota of North America Program 2014 county distribution map] It is also naturalized in various other regions, and has been declared a noxious weed in Australia[http://vro.depi.vic.gov.au/dpi/vro/vrosite.nsf/pages/pot_dist_burr_ragweed State of Victoria, Victorian Resources Online, Map of Potential Distribution of Burr ragweed (Ambrosia confertiflora) in Victoria][http://bie.ala.org.au/species/urn:lsid:biodiversity.org.au:apni.taxon:562121 Atlas of Living Australia, Ambrosia confertiflora DC. Burr Ragweed][http://www.southeastweeds.org.au/index.pl?page=134 Southern Tablelands and South Coast Noxious Plants Committee (New South Wales), burr ragweed] and in Israel.{{Cite web|url=http://www.sviva.gov.il/InfoServices/ReservoirInfo/DocLib2/Publications/P0701-P0800/P0707.pdf|title=Ambrosia confertiflora – Burr Ragweed – Information booklet|last1=Dufour-Dror|first1=Jean-Marc|last2=Yaakobi|first2= Tuvia|date=1 May 2013|website=Israeli Ministry of Environmental Protection|access-date=1 October 2018}} It grows in disturbed sites.

References

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