{{short description|Species of plant}} {{Speciesbox |name = Sugar gum |image = Eucalyptus cladocalyx (1).jpg |image_caption=''Eucalyptus cladocalyx'' habit |status = VU |status_system = IUCN3.1 | status_ref = <ref>{{cite iucn |author=Fensham, R. |author2=Laffineur, B. |author3=Collingwood, T. |year=2019 |title=''Eucalyptus cladocalyx'' |volume=2019 |article-number=e.T133378591A133378593 |doi=10.2305/IUCN.UK.2019-3.RLTS.T133378591A133378593.en |access-date=22 September 2021}}</ref> |genus = Eucalyptus |species = cladocalyx |authority = F.Muell.<ref name=APC>{{cite web|title=''Eucalyptus cladocalyx''|url= https://biodiversity.org.au/nsl/services/apc-format/display/112610|publisher=Australian Plant Census|access-date=30 April 2019}}</ref> |range_map = E. cladocalyx.JPG |range_map_caption = ''E. cladocalyx'', field distribution |synonyms_ref =<ref name="APC" /> |synonyms = ''Eucalyptus corynocalyx'' <small>F.Muell. nom. illeg., nom. superfl.</small> }}
thumb|''Eucalyptus cladocalyx'' leaves and bark thumb|Kino oozing from a small fissure on a ''Eucalyptus cladocalyx'' thumb|''Eucalyptus cladocalyx'' fruit [[File:Two Sugar Gums growing next to the Wollundry Lagoon in the Victory Memorial Gardens.jpg|thumb|Two sugar gums growing next to the Wollundry Lagoon in Wagga Wagga]]
'''''Eucalyptus cladocalyx''''', commonly known as '''sugar gum''', is a species of eucalypt tree found in the Australian state of South Australia. It is found naturally in three distinct populations - in the Flinders Ranges, Eyre Peninsula and on Kangaroo Island.
==Description== The tree notable for its mottled colourful yellow to orange bark, strongly discolourous leaves and inflorescences grouped on leafless branchlets inside the tree crown. The old bark is smooth and grey, shedding in irregular patches to expose the fresh yellowy-brown bark. Flowers are creamy-white in summer. The capsules are barrel to urn shaped.
Sugar gums in the Flinders Ranges reach up to {{convert|35|m|ft|0}} in height<ref name=florabank>{{cite web |url=http://www.florabank.org.au/lucid/key/species%20navigator/media/html/Eucalyptus_cladocalyx.htm |title=''Eucalyptus cladocalyx'' |access-date=30 July 2017 |publisher=Florabank |archive-date=29 May 2017 |archive-url=https://web.archive.org/web/20170529021602/http://www.florabank.org.au/lucid/key/species%20navigator/media/html/Eucalyptus_cladocalyx.htm |url-status=dead }}</ref> and have the classic "gum" habit, with a straight trunk having a diameter at breast height (dbh) of {{cvt|1|to|1.5|m|abbr=on}} and steep branches occurring about halfway up. Each main branch ends with its own little canopy. They are commonly cultivated as farm windbreaks and for timber. However, Eyre Peninsula and Kangaroo Island trees are much shorter, typically between {{cvt|8|and|15|m|abbr=on}} in height, and often have crooked trunks and a dbh of {{cvt|0.4|m|abbr=on}}.<ref name=florabank/> The crown has an open spreading habit with a typical spread of {{cvt|12|to|15|m|abbr=on}}.<ref name=ps/>
The strongly discolorous, glossy adult leaves are arranged alternately supported on a petiole that is {{cvt|0.9|to|2.7|cm}} in length. The leaf blade is darker green on upper side and paler below with slightly falcate to lanceolate shape, a length of {{cvt|8|to|17|cm|abbr=on}} and a width of {{cvt|1.2|to|3.2|cm|abbr=on}}, with a base usually tapering to the petiole. The side-veins in the leaf are at an acute or wider angle and densely reticulate. The intramarginal vein is parallel to but removed from margin, with small and obscure oil glands.<ref name=euclid>{{cite web|url=https://apps.lucidcentral.org/euclid/text/entities/eucalyptus_cladocalyx.htm|title=''Eucalyptus cladocalyx''|work=Euclid|access-date=4 June 2020|publisher=CSIRO}}</ref>
It flowers in summer, producing white-cream-yellow flowers.<ref name=ps>{{cite web |url=http://plantselector.botanicgardens.sa.gov.au/Plants/Details/3246 |title=''Eucalyptus cladocalyx'' |work=Factsheet |access-date=25 November 2018 |publisher=Botanic Gardens of South Australia}}</ref> The axillary unbranched inflorescence occur in groups of buds 7, 9 or 11 buds per umbel. The oblong pale green, yellow to creamy mature buds have a length of {{cvt|0.8|to|1.1|cm}} and a width of {{cvt|0.4|to|0.5|cm|abbr=on}}. The buds are often longitudinally striated and scarred, with a rounded operculum, inflexed stamens and cuboid to oblong anthers. The urceolate or barrel-shaped, longitudinally ribbed fruits that form after flowering are {{cvt|0.7|to|1.5|cm|abbr=on}} in length and {{cvt|0.5|to|1|cm|abbr=on}} wide, with a descending disc and three or four enclosed valves. The light grey to brown seeds within the fruit have a flattened-ovoid shape that can be pointed at one end and are {{cvt|1.5|to|3|mm}} long.<ref name=euclid/>
==Taxonomy== The species was first formally described in 1853 by the botanist Ferdinand von Mueller, in the journal ''Linnaea: Ein Journal für die Botanik in ihrem ganzen Umfange, oder Beiträge zur Pflanzenkunde''.<ref name=APNI>{{cite web|title=''Eucalyptus cladocalyx''|url= https://id.biodiversity.org.au/instance/apni/455993|publisher=APNI|access-date=30 April 2019}}</ref><ref name="Linnaea">{{cite journal |last1=von Mueller |first1=Ferdinand |author-link1=Ferdinand von Mueller |title=Diagnoses et descriptiones plantarum novarum, quas in Nova Hollandia |journal=Linnaea: Ein Journal für die Botanik in ihrem ganzen Umfange |date=1853 |volume=25 |page=388 |url=https://www.biodiversitylibrary.org/item/10869#page/391/mode/1up |access-date=30 April 2019}}</ref>
In 1860, von Mueller referred to ''Eucalyptus corynocalyx'' in ''Fragmenta phytographiae Australiae'',<ref name="Fragmenta">{{cite book |last1=von Mueller |first1=Ferdinand |author-link1=Ferdinand von Mueller |title=Fragmenta phytographiae Australiae (Volume 2) |date=1860 |volume=2 |publisher=Victorian Government Printer |location=Melbourne |page=43 |url=https://www.biodiversitylibrary.org/item/7219#page/46/mode/1up |access-date=30 April 2019}}</ref> citing several earlier publications, including the ''Linnaea'' journal article, but all only have a description of ''E. cladocalyx''. ''Eucalyptus corynocalyx'' is therefore a nomen illegitimum and a synonym of ''E. cladocalyx''.<ref name=APNI1>{{cite web|title=''Eucalyptus corynocalyx''|url= https://id.biodiversity.org.au/instance/apni/456074|publisher=APNI|access-date=30 April 2019}}</ref>
The specific epithet is taken from the Ancient Greek words ''klados'', meaning ''branch'', "twig" or "stem"<ref name="RWB">{{cite book|last1=Brown|first1=Roland Wilbur|author-link1=Roland W. Brown|title=The Composition of Scientific Words|date=1956|publisher=Smithsonian Institution Press|location=Washington, D.C.}}</ref>{{rp|162}} and ''kalyx'', meaning "cup", "cover" or "outer envelope of a flower",<ref name="RWB" />{{rp|181}} in reference to the leafless branchlets that bear the flowers.<ref name=euclid/>
In 2013, Dean Nicolle describe three subspecies of ''E. cladocalyx'' and the names have been accepted by the Australian Plant Census:<ref name="Nicolle">{{cite book |last1=Nicolle |first1=Dean |title=Native eucalypts of South Australia |date=2013 |publisher=Dean Nicolle |location=Adelaide |isbn=978-0-646-90410-8 |pages=30–35}}</ref> * ''Eucalyptus cladocalyx'' <small>F.Muell.</small> subsp. ''cladocalyx''<ref name=APC1>{{cite web|title=''Eucalyptus cladocalyx''|url= https://biodiversity.org.au/nsl/services/apc-format/display/243560|publisher=Australian Plant Census|access-date=30 April 2019}}</ref> is a lower-growing, more spreading tree than the other subspecies and has short, broad leaves and larger fruit; * ''Eucalyptus cladocalyx'' subsp. ''crassa'' <small>D.Nicolle</small><ref name=APC2>{{cite web|title=''Eucalyptus cladocalyx'' subsp. ''crassa''|url= https://biodiversity.org.au/nsl/services/apc-format/display/243561|publisher=Australian Plant Census|access-date=30 April 2019}}</ref> is the tallest-growing subspecies and has long, narrow leaves and large fruit; * ''Eucalyptus cladocalyx'' subsp. ''petila'' <small>D.Nicolle</small><ref name=APC3>{{cite web|title=''Eucalyptus cladocalyx'' subsp. ''petila''|url= https://biodiversity.org.au/nsl/services/apc-format/display/243562|publisher=Australian Plant Census|access-date=30 April 2019}}</ref> is a tall subspecies with erect branches, narrow adult leaves and relatively small fruit.<ref name="Nicolle" />
==Distribution== ''Eucalyptus cladocalyx'' is endemic to a few limited areas in southern South Australia. There are three distinct populations: in the southern and central-eastern parts of the Eyre Peninsula, through much of the Flinders Ranges, and on Kangaroo Island. It is most likely part of relic forests of wetter climates from the past.<ref name=euclid/><ref name="Brooker">{{cite book |last1=Brooker |first1=M. Ian H. |title=Field guide to eucalypts (Volume 1) |date=2006 |publisher=Bloomings Books Pty Ltd |isbn=978-1-876473-52-5 |edition=3rd |page=68}}</ref>
''E. cladocalx'' has now become naturalised in the South West region of Western Australia, in southern Victoria, and in some parts of south-eastern South Australia, beyond its native range. It is also naturalised overseas in northern and southern Africa, California, Hawaii,<ref name=weed>{{cite web|url=https://keyserver.lucidcentral.org/weeds/data/media/Html/eucalyptus_cladocalyx.htm|title=''Eucalyptus cladocalyx'' F.Muell.|work=Weeds of Australia|access-date=30 July 2017|publisher=Queensland Government}}</ref> Arizona, Israel, Chile, Greece, Portugal and Spain.<ref name=cabi/>
Subspecies ''cladocalyx'' is restricted to the southern and eastern Eyre Peninsula, subspecies ''crassa'' to Kangaroo Island and subspecies ''petila'' to the southern Flinders Ranges.<ref name="Nicolle" />
==Uses== The tree has been widely planted across southern Australia, often as a windbreak or shelterbelt, but also for timber and firewood production. The wood is termite resistant, with moderate strength and durability, and can be used for furniture, flooring, posts, construction timber and railway sleepers.<ref name=florabank/>
It is a fast-growing tree but is best planted in open sun in clay, loamy or sandy soils.<ref name=ps/> It is an efficient user of water<ref name=cabi/> and drought and frost tolerant, with flowers that attract bees. It is also known to be a suitable breeding habitat for the Yellow-tailed Black-Cockatoo.<ref name=ps/>
''E. cladocalyx'' is well adapted to regular bushfires and can resprout epicormically. It also produces a large number of seedlings through wind dispersal of seeds.<ref name=cabi>{{cite web|url=https://www.cabi.org/isc/datasheet/22599|title=''Eucalyptus cladocalyx'' (sugar gum)|access-date=25 November 2018|work=Invasive Species Compendium|publisher=Centre for Agriculture and Bioscience International}}</ref>
The hard and heavy heartwood is a pale yellow-brown colour and has fine uniform texture with an interlocked grain. The density of air-dried wood is around {{cvt|1105|kg/m3}} and is moderately durable.<ref name=fpc>{{cite web|url=http://www.fpc.wa.gov.au/node/971|title=Sugar gum ''Eucalyptus cladocalyx''|access-date=25 November 2018|publisher=Forest Products Commission Western Australia|archive-date=25 November 2018|archive-url=https://web.archive.org/web/20181125162725/http://www.fpc.wa.gov.au/node/971|url-status=dead}}</ref><ref name="Wood Solutions">{{cite web |url=https://www.woodsolutions.com.au/wood-species/gum-sugar |website=Wood Solutions |title=Gum, Sugar|publisher=Forest and Wood Products Australia Ltd |access-date=19 June 2019 |ref=WS}}</ref>
The dwarf subspecies ''cladocalyx'' is sold in the nursery trade as ''E. cladocalyx'' 'Nana'.<ref name="Nicolle" />
==Weed potential== ''E. cladocalyx'' has invaded bushland in Western Australian, where it was introduced. It has the capacity to spread up to 70 metres away from locations where it has been planted, and seems to survive bush fires more effectively than several endemic eucalypt species. It has become an invasive species in South Africa, where it is now registered as a category 2 invader plant.<ref>{{cite web |title=Eucalyptus cladocalyx (sugar gum) |url=https://www.cabi.org/isc/datasheet/22599#tosummaryOfInvasiveness |website=Invasive Species Compendium |publisher=CAB International |access-date=2022-07-25}}</ref>
==References== {{Reflist}} * Holliday, I. ''A field guide to Australian trees (3rd edition)'', Reed New Holland, 2002 * Cronin, L. ''Key Guide to Australian Trees'', Envirobook, 2000 * [http://www.anbg.gov.au/cpbr/summer-scholarship/2001-projects/rawlings-mathew.html Rawlings, M. ''Regional allozyme divergence in Sugar Gum, Eucalyptus cladocalyx'', 2005, Centre for Plant Biodiversity Research]
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{{DEFAULTSORT:Eucalyptus cladocalyx}} Category:Trees of Australia Category:Trees of Mediterranean climate cladocalyx Category:Flora of South Australia Category:Myrtales of Australia Category:Plants described in 1853 Category:Taxa named by Ferdinand von Mueller