{{Short description|Species of legume}} {{Use dmy dates|date=July 2019}} {{Speciesbox | name = Cactus bossiaea | image = Bossiaea walkeri.jpg | image_caption = ''Bossiaea walkeri'' in Maranoa Gardens | genus = Bossiaea | species = walkeri | authority = F.Muell.<ref name=APC>{{cite web|title=''Bossiaea walkeri''|url= https://biodiversity.org.au/nsl/services/apc-format/display/62969|publisher=Australian Plant Census|access-date=30 September 2021}}</ref> | range_map = BossiaeawalkeriDistMap100.png | range_map_caption = Occurrence data from AVH }}
'''''Bossiaea walkeri''''', commonly known as '''cactus bossiaea''', '''cactus pea''',<ref name="RBGS">{{cite web |title=''Bossiaea walkeri'' |url=https://plantnet.rbgsyd.nsw.gov.au/cgi-bin/NSWfl.pl?page=nswfl&lvl=sp&name=Bossiaea~walkeri |publisher=Royal Botanic Garden Sydney |access-date=30 September 2021}}</ref> or '''Walker's stick bush''',<ref name=":0">{{Cite web|last=Australian National Botanic Gardens|first=Parks Australia|title=''Bossiaea walkeri'' - Growing Native Plants|url=https://www.anbg.gov.au/gnp/interns-2010/bossiaea-walkeri.html|access-date=2020-10-25|website=www.anbg.gov.au|language=en}}</ref> is a species of flowering plant in the pea family (Fabaceae) and is endemic to southern mainland Australia. It is a rigid, much-branched shrub with flattened, winged cladodes and red, pea-like flowers between July and November in the species' native range.
==Description== ''Bossiaea walkeri'' is a rigid, much-branched shrub that grows up to {{cvt|2|m}} high and wide and is more or less glabrous. The stems and branches are flattened and winged, ending in cladodes {{cvt|3–7|mm}} wide. The leaves, when present, are reduced to scales about {{cvt|2|mm}} long, occasionally more or less round and up to {{cvt|15|mm}} long near the base or on young plants. The flowers are {{cvt|20–25|mm}} long and are borne singly at nodes on the cladodes on a pendent pedicel up to {{cvt|5|mm}} long with overlapping, broadly egg-shaped bracts up to {{cvt|3|mm}} long at the base. There are egg-shaped bracteoles {{cvt|2.3–3.5|mm}} long on the pedicel, but that fall off as the flower opens. The five sepals are about {{cvt|10|mm}} long and joined at the base, forming a tube {{cvt|3.5–6.0|mm}} long, the two upper lobes {{cvt|2.3–5.5|mm}} long and much longer than the lower three. The standard petal is usually red, {{cvt|18–19|mm}} long and shorter than the wings and keel that are each about {{cvt|20|mm}} long. The wings are salmon pink and the keel is deep red. Flowering occurs between July and November and the fruit is an oblong pod about {{cvt|6|mm}} long.<ref name="RBGS" /><ref name="FloraBase">{{FloraBase | name = ''Bossiaea walkeri''| id = 3722}}</ref><ref name=SSA>{{Cite web|title=Seeds of South Australia - Species Information|url=https://spapps.environment.sa.gov.au/SeedsOfSA/speciesinformation.html?rid=717|access-date=2020-10-24|website=spapps.environment.sa.gov.au}}</ref><ref name="RBGV">{{cite web |last1=Ross |first1=James H. |title=''Bossiaea walkeri'' |url=https://vicflora.rbg.vic.gov.au/flora/taxon/f55b07c5-b6da-4bc0-8d53-8bb063ab9a4d |publisher=Royal Botanic Gardens Victoria |access-date=30 September 2021}}</ref><ref name="Muelleria">{{cite journal |last1=Ross |first1=James H. |title=A conspectus of the Western Australian ''Bossiaea'' species (Bossiaeeae: Fabaceae). |journal=Muelleria |date=2006 |volume=23 |pages=118–121 |url=https://www.biodiversitylibrary.org/item/278250#page/120/mode/1up |access-date=30 September 2021}}</ref><ref name="Corrick">{{cite book |last1=Corrick |first1=Margaret G. |last2=Fuhrer |first2=Bruce A. |title=Wildflowers of southern Western Australia |date=2009 |publisher=Rosenberg Pub |location=Kenthurst, N.S.W. |isbn=9781877058844 |page=57 |edition=3rd}}</ref>
==Taxonomy== ''Bossiaea walkeri'' was first formally described in 1861 by Ferdinand von Mueller in ''Fragmenta Phytographiae Australiae'' from specimens collected by Alexander Walker on hills between the Lachlan and Murrumbidgee Rivers.<ref name=APNI>{{cite web|title=''Bossiaea walkeri''|url= http://id.biodiversity.org.au/instance/apni/468799 |publisher=APNI|access-date=30 September 2021}}</ref><ref name="F. Muell.">{{cite book |last1=von Mueller |first1=Ferdinand |title=Fragmenta Phytographiae Australiae |volume=2 |date=1861 |publisher=Victorian Government Printer |location=Melbourne |page=120 |url=https://www.biodiversitylibrary.org/item/7219#page/125/mode/1up |access-date=30 September 2021}}</ref> The specific epithet (''walkeri'') honours the collector of the type specimens.<ref name="Sharr">{{cite book |last1=Sharr |first1=Francis Aubi |last2=George |first2=Alex |title=Western Australian Plant Names and Their Meanings |date=2019 |publisher=Four Gables Press |location=Kardinya, WA |isbn=9780958034180 |page=338 |edition=3rd}}</ref>
== Distribution and habitat == Cactus bossiaea grows in mallee, low open woodland, creek beds and rocky outcrops and occurs in Western Australia, South Australia, Victoria and New South Wales. It is found from near Shark Bay in Western Australia, through the south-west of the state to southern South Australia, the Murray River and Wyperfeld National Park in Victoria, and to inland New South Wales.<ref name="RBGS" /><ref name="FloraBase" /><ref name="SSA" /><ref name="RBGV" /><ref name="Muelleria" /> The species is rare in Victoria, where it is listed as "endangered" under the Victorian Government ''Flora and Fauna Guarantee Act 1988''.<ref name="RBGV" />
==Ecology== The pendent flowers and the unusual shape of the flower parts of ''B. walkeri'' suggest that it is bird-pollinated. Honeyeaters and blue wrens have been observed visiting the flowers.<ref name="Muelleria" />
== Reproduction == The 2cm flowers are produced between July and November. They will often flower after seed has set to take full advantage of additional rainfall after a dry period.<ref name=":1" /> The fruit is a hairless, flattened 6cm by 1cm pod that contains brown seeds. The pods begin green but mature to brown, the seeds become ripe usually 2 to 3 months after flowering has finished.<ref name=":0" /> Then on a hot day the pods will explode to disperse the seed several metres. Birds are the primary pollinators, but small animals and insects also contribute.<ref name=":1">{{Cite web|last=Archer|first=William|date=2010-01-30|title=Esperance Wildflowers: Cactus Pea - Bossiaea walkeri|url=http://esperancewildflowers.blogspot.com/2010/01/cactus-pea-bossiaea-walkeri.html|access-date=2020-10-25|website=Esperance Wildflowers}}</ref>
==Uses== ===Use in horticulture=== This species is described as "decorative" and can be propagated from seed or from cuttings. It can be grown in full sun or part shade, is drought and frost tolerant but needs relatively dry, well-drained soil.<ref name=":0" />
===Other uses=== ''Bossiaea walkeri'' produces a very distinct honey, although it appears to have no pastoral value.<ref name=":0" />
==References== {{Reflist}}
{{Taxonbar|from=Q10740874}}
walkeri Category:Flora of New South Wales Category:Flora of Victoria (state) Category:Rosids of Western Australia Category:Flora of South Australia Category:Taxa named by Ferdinand von Mueller