{{Short description|Biological structure in a plant stem}} [[Image:Dicksonia_antarctica_(Tasmanian_Fern_Tree).jpg|thumb|The caudex of a tree fern resembles the trunk of a woody plant, but has a different structure.]] [[Image:Jatropha cathartica2 ies.jpg|thumb|The caudex of ''Jatropha cathartica'' is pachycaul, with thickening that provides water storage.]] [[File:Caudexacanthocereusmaculatus.jpg|thumb|Certain cacti can develop a caudex too; here ''Acanthocereus maculatus'']] A '''caudex''' ({{plural form}}: '''caudices''') of a plant is a stem,<ref name=Hickey>{{cite book|author1=Hickey, M. |author2=King, C. |year=2001|title=The Cambridge Illustrated Glossary of Botanical Terms|publisher=Cambridge University Press}}</ref> but the term is also used to mean a rootstock<ref name=Stearn>{{cite book|author=Stearn, W.T.|year=1992|title=Botanical Latin: History, grammar, syntax, terminology and vocabulary, Fourth edition|publisher=David and Charles}}</ref> and particularly a basal stem structure from which new growth arises.<ref name=Simpson>{{cite book|author=Simpson, M.G.|year=2010|title=Plant Systematics: Second Edition|publisher=Elsevier Science|isbn=9780080922089|url=https://books.google.com/books?id=dj8KRImgyf4C&q=caudex}}pages 456 and 695</ref>
In the strict sense of the term, meaning a stem, "caudex" is most often used with plants that have a different stem morphology from the typical angiosperm dicotyledon stem;<ref name=Hickey/> examples include palms, ferns, and cycads. The largest of all caudices is that of the ombu (''Phytolacca dioica'') of the Pampas of South America, which can reach up to 14 metres girth.<ref>{{cite web | title=Ombú in the Isla de la Cartuja in Sevilla, Andalusia, Spain | website=Monumental trees | date=2021-12-23 | url=https://www.monumentaltrees.com/en/esp/andalusia/sevilla/29823_isladelacartuja/ | access-date=2025-08-21}}</ref>
The related term '''caudiciform''', literally meaning stem-like, is sometimes used to mean pachycaul, thick-stemmed.<ref name=Simpson/> Caudices should not be confused with lignotubers which can also be very large.
== Etymology == The term derives from the Latin ''caudex'', a noun meaning "tree trunk"; 'codex' is an alternate form of the same word.<ref name=Stearn/><ref>{{cite web|url=http://www.thefreedictionary.com/caudex |title=caudex - definition of caudex by The Free Dictionary |publisher=Thefreedictionary.com |access-date=2014-07-15}}</ref><ref>{{cite book|author=Lewis & Short|title=A Latin Dictionary|url=https://logeion.uchicago.edu/caudex|entry=caudex}}</ref>
==See also== * Stipe
=== References === {{Reflist}}
== External links == {{wiktionary}} {{Commons category|Caudices}} *[http://www.bihrmann.com/caudiciforms/fami/fami.asp Bihrmann's Caudiciforms] ''Extensive listing of caudiciforms, images for most species'' *[http://waynesword.palomar.edu/ecoph30.htm#caudiciform Wayne's Word] {{Webarchive|url=https://web.archive.org/web/20090319142333/http://waynesword.palomar.edu/ecoph30.htm#caudiciform |date=2009-03-19 }} ''Caudiciform Plants With An Enlarged Caudex''
Category:Plant anatomy Category:Plant stem morphology