Alnus rhombifolia

{{Short description|Species of tree}}

{{Speciesbox

|name=White alder

|image=Alnus rhombifolia NPS.jpg

|image_caption=Foliage and fruit

|status=LC

|status_system=IUCN3.1

|status_ref={{cite journal |author=Stritch, L. |name-list-style=amp |title=Alnus rhombifolia |journal=The IUCN Red List of Threatened Species |volume=208 |at=e.T194648A2355642. |publisher=IUCN |year=2014 |doi=10.2305/IUCN.UK.2014-3.RLTS.T194648A2355642.en |doi-access=free }}

|genus=Alnus

|parent=Alnus subg. Alnus

|species=rhombifolia

|authority=Nutt.

|range_map=Alnus rhombifolia range map 1.png

|range_map_caption=Natural range of Alnus rhombifolia

}}

Alnus rhombifolia, the white alder, is an alder tree native to western North America, from British Columbia and Washington east to western Montana, southeast to the Sierra Nevada, and south through the Peninsular Ranges and Colorado Desert oases in Southern California.{{cite web |url=http://ucjeps.berkeley.edu/cgi-bin/get_JM_treatment.pl?Alnus+rhombifolia |title=UC/JEPS: Jepson Manual treatment for ALNUS rhombifolia |website=ucjeps.berkeley.edu |access-date=2010-09-29}} It occurs in riparian zone habitats at an altitudes range of {{convert|100|–|2400|m|ft}}.Flora of North America: [http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=233500038 Alnus rhombifolia]{{GRIN | accessdate=22 December 2017}} While not reported in northern Baja California, it has been predicted on the basis of its climatic adaptation to occur there also. Alnus rhombifolia is primarily found in the chaparral and woodlands, montane, and temperate forests ecoregions.

Description

Alnus rhombifolia is a medium-sized deciduous tree growing to {{convert|15|–|25|m|ft}} (rarely to {{convert|35|m|ft}}) tall, with pale gray bark, smooth on young trees, becoming scaly on old trees. The leaves are alternate, rhombic to narrow elliptic, {{convert|4|–|10|cm|in}} long and {{convert|2|–|5|cm|in}} broad, with a finely serrated margin and a rounded to acute apex; they are thinly hairy below.http://calphotos.berkeley.edu/cgi/img_query?query_src=photos_index&where-lifeform=any&rel-taxon=contains&where-taxon=Alnus+rhombifolia&rel-namesoup=matchphrase&where-namesoup=&rel-location=matchphrase&where-location=&rel-county=eq&where-county=any&rel-state=eq&where-state=any&rel-country=eq&where-country=any&where-collectn=any&rel-photographer=contains&where-photographer=&rel-kwid=equals&where-kwid=&max_rows=24 calphoto . accessed 9/29/2010

The flowers are produced in catkins. The male catkins are pendulous, slender, {{convert|3|–|10|cm|in}} long, yellowish, and produced in clusters of two to seven; pollination is in early spring, before the leaves emerge. The female catkins are ovoid, when mature in autumn {{convert|10|–|22|mm|in}} long and {{convert|7|–|10|mm|in}} broad, on a {{convert|1|–|10|mm|in}} stem, superficially resembling a small conifer cone. The small winged seeds disperse through the winter, leaving the old woody, blackish 'cones' on the tree for up to a year after.Oregon State University: [https://landscapeplants.oregonstate.edu/plants/alnus-rhombifolia Alnus rhombifolia]

The white alder is closely related to the red alder (Alnus rubra), differing in the leaf margins being flat, not curled under. Like other alders, it is able to fix nitrogen, and tolerates infertile soils.

Medicinal use

Some Plateau Indian tribes use white alder for female health treatment needs.{{cite book |last=Hunn |first=Eugene S. |title=Nch'i-Wana, "The Big River": Mid-Columbia Indians and Their Land |publisher=University of Washington Press |year=1990 |isbn=0-295-97119-3| page=351}}

References

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