View source for Biology:Rhododendron macrophyllum

{{Speciesbox
|name = Pacific rhododendron
|image = Rhododendron macrophyllum 4861.JPG
|image_caption = In the Olympic Peninsula, {{wipe|Washington (state)}}
|parent = Rhododendron sect. Pontica
|taxon = Rhododendron macrophyllum
|authority = D.Don ex G.Don 1834
|synonyms = ''Rhododendron californicum'' {{small|Hook.}}
|synonyms_ref = <ref>{{GRIN}}</ref>
|range_map = Rhododendron macrophyllum range map.png
|range_map_caption = Natural range
}}

'''''Rhododendron macrophyllum''''', the '''Pacific rhododendron''',<ref>{{PLANTS|id=RHMA3|taxon=Rhododendron macrophyllum|access-date=21 October 2015}}</ref> '''California rosebay''',<ref name=BSBI07>{{BSBI 2007 |access-date=2014-10-17 }}</ref> '''California rhododendron''', '''coast rhododendron''' or '''big leaf rhododendron''', is a large-leaved species of ''[[Biology:Rhododendron|Rhododendron]]'' native to the Pacific Coast of [[Earth:North America|North America]]. It is the state flower of {{wipe|Washington (state)}}.<ref>[http://www.leg.wa.gov/Symbols/Pages/default.aspx Symbols of Washington State]</ref>

== Description ==
It is an [[Biology:Evergreen|evergreen]] [[Biology:Shrub|shrub]] growing up to {{Convert|2-9|m|ft|0|abbr=on}} tall. The [[Biology:Leaf|leaves]], retained for 2–3 years, are {{Convert|7-23|cm|0|abbr=on}} long and {{Convert|3-7|cm|0|abbr=on}} broad. The [[Biology:Flower|flower]]s are {{Convert|2.8-4|cm|abbr=on}} long, with five lobes on the [[Biology:Petal|corolla]]; color is usually pink, although variants exist.

== Distribution ==
The northern limit of its range is somewhat north of the border between {{wipe|Canada}} and the {{wipe|United States}} in British Columbia. It is found as far south as Monterey Bay in {{wipe|California}}.<ref name="FEIS">{{FEIS |last=Crane |first=M. F. |date=1990 |type=shrub |genus=Rhododendron |species=macrophyllum}}</ref> It is widely distributed in the Coast Mountains and Cascade Range. It is less abundant in the coastal mountains of Washington and northern Oregon and more common south of the Siuslaw River. It is mostly coastal in distribution but extends its range eastward to locations in the Cascade Mountains in Oregon, Washington and British Columbia.<ref name="FEIS" />

== Habitat ==
''Rhododendron macrophyllum'', like many rhododendrons, thrives in disturbed habitats such as roadside embankments and recently deforested wildlands. They can also live up in the mountains. It also grows in coastal and montane conifer woods.<ref>{{Cite web|title=Lady Bird Johnson Wildflower Center - The University of Texas at Austin|url=https://www.wildflower.org/plants/result.php?id_plant=rhma3|access-date=2022-01-01|website=www.wildflower.org}}</ref>

== History and cultivation ==
[[Biography:Archibald Menzies|Archibald Menzies]] found ''R. macrophyllum'' growing along with ''[[Biology:Arbutus menziesii|Arbutus menziesii]]'' in May 1792 when he and George Vancouver made their second landfall after leaving Hawaii, near present-day Port Discovery, Washington.<ref name=cjustice>Justice, Clive L. Mr. Menzies' Garden Legacy, Plant Collecting on the Northwest Coast. 2000. Cavendish Books. {{ISBN|978-1-55289-020-2}}</ref> Seed was sent to England in 1850 by [[Biography:William Lobb|William Lobb]].

In recent years it has been the main focus of a study group at the [[Organization:Rhododendron Species Foundation and Botanical Garden|Rhododendron Species Foundation]] in Federal Way, Washington, the Western North American Rhododendron Species Project.<ref>{{cite web |url=http://www.wnarsp.org/ |title=Western North American Rhododendron Species Project (WNARSP)}}</ref> The WNARSP is documenting the detailed range and forms of all of the western North American rhododendron species.

== Toxicity ==
The species contains andromedotoxin, which can poison the honey of nearby hives.<ref>{{Cite book|last=Fagan|first=Damian|url=https://www.worldcat.org/oclc/1073035766|title=Wildflowers of Oregon: A Field Guide to Over 400 Wildflowers, Trees, and Shrubs of the Coast, Cascades, and High Desert|publisher=FalconGuides|year=2019|isbn=1-4930-3633-5|location=Guilford, CT|pages=195|oclc=1073035766}}</ref>

== References ==
{{Reflist}}

== Other sources ==
*Davidian, H. H. ''The Rhododendron Species, Volume III – Elepidotes continued''. 1992.  Timber Press.  {{ISBN|978-0-88192-168-7}}.
*Cox, Peter A. & Kenneth N.E. ''The Encyclopedia of Rhododendron Species''. 1997. Glendoick Publishing. {{ISBN|978-0-9530533-0-8}}.

== External links ==
* {{Commons and category-inline}}

{{Taxonbar|from=Q2714739}}

[[Category:Rhododendron|macrophyllum]]

{{Sourceattribution|Rhododendron macrophyllum}}