Editing Stipule

{{Short description|Appendage of a leaf in flowering plants}}
In [[botany]], a '''stipule''' is an outgrowth typically borne on both sides (sometimes on just one side) of the base of a leafstalk (the [[petiole (botany)|petiole]]). They are primarily found among [[dicots]] and rare among [[monocots]]. Stipules are considered part of the anatomy of the [[leaf]] of a typical [[flowering plant]], although in many species they may be inconspicuous —or sometimes entirely absent, and the leaf is then termed '''''exstipulate'''''. At the other end of the scale are species like ''[[Artocarpus elasticus]]'' where the stipules can be up to eight inches (twenty cm) in length. (In some older botanical writing, the term "stipule" was used more generally to refer to any small leaves or leaf-parts, notably [[prophyll]]s.)<ref>{{cite book|url=https://archive.org/details/organographyofpl02goeb|title=Organography of plants, especially of the Archegoniatae and Spermaphyta|publisher=Hofner publishing company|year=1969|volume=Part 2 Special organography|location=New York|author=Goebel, K.E.v.|orig-year=1905|translator=I.B. Balfour}}</ref> The word  ''stipule'' was coined by [[Carl Linnaeus|Linnaeus]]<ref name=CED>''Concise English Dictionary'' Wordsworth Editions Ltd. 1994, {{ISBN|1-85326-328-1}}</ref> from [[Latin]] ''stipula'', straw, stalk.

==Types of stipules==
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[[Image:E pteroneura ies.jpg|thumb|left|197px|<br/>&nbsp;<br/><span style="font-size:100%;">Glandular stipule of ''[[Euphorbia pteroneura]]''</span>]]
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[[File:N Prop S0162.jpg|thumb|left|197px|<br/>&nbsp;<br/><span style="font-size:100%;">Stipular spines on the [[mesquite]] tree (''[[Prosopis pallida]]'')</span>]]
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[[Image:Alchemilla mollis ies.jpg|thumb|left|197px|<br/>&nbsp;<br/><span style="font-size:100%;">Fused together and leaf-like stipules of ''[[Alchemilla mollis]]''</span>]]
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[[Image:Rosa canina blatt 2005.05.26 11.50.13.jpg|thumb|left|197px|<br/>&nbsp;<br/><span style="font-size:100%;">Leafy stipules at the base of a [[Rose]] leaf (''[[Rosa canina]]'')</span>]]
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[[Image:Jatropha spicata ies.jpg|thumb|left|197px|<br/>&nbsp;<br/><span style="font-size:100%;">Stipules building glandular hairs on ''[[Jatropha spicata]]''</span>]]
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[[Image:Carpinus betulus ies.jpg|thumb|left|197px|<br/>&nbsp;<br/><span style="font-size:100%;">Stipules protecting young leaves of ''Carpinus betulus'' ([[European Hornbeam]])</span>]]
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[[Image:Monadenium spectabile ies.jpg|thumb|left|210px|<br/>&nbsp;<br/><span style="font-size:100%;">Stipular spine clusters of ''[[Euphorbia spectabilis]]''</span>]]
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[[Image:E didieroides ies.jpg|thumb|left|210px|<br/>&nbsp;<br/><span style="font-size:100%;">Stipular spines accompanied by prickles of ''[[Euphorbia didiereoides]]''</span>]]
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[[File:菩提樹 Ficus religiosa 20210421111446 01.jpg|thumb|left|210px|<br/>&nbsp;<br/><span style="font-size:100%;">The stipule of ''[[Ficus religiosa]]''. The white "stipule" contains a new leaf and a new "stipule".</span>]]
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== General characteristics ==
The position of stipules on a plant varies widely from species to species, though they are often located near the base of a leaf. Stipules are most common on dicotyledons, where they appear in pairs alongside each leaf. Some monocotyledon plants display stipule-like structures, but only display one per leaf. A relationship exists between the anatomy of the stem node and the presence or absence of stipules: most plants with ''trilacunar'' [[Node (botany)|nodes]] have stipules; species with ''unilacunar'' nodes lack stipules.<ref>{{cite journal|author=Sinnott, E. W.|author2=I. W. Bailey|name-list-style=amp|jstor=2435043|year=1914|title=Investigations on the phylogeny of the angiosperms. 3. Nodal anatomy and the morphology of stipules|journal=American Journal of Botany|volume=1|issue=9|pages=441–453|doi=10.2307/2435043|url=https://www.biodiversitylibrary.org/part/312592 }}</ref>

Stipules are morphologically variable and might appear as [[gland (botany)|gland]]s, scales, [[Trichome|hairs]], [[Spine (botany)|spines]], or laminar (leaf-like) structures.

If a single stipule goes all the way around the stem, it is known as an [[ochrea]].<ref name=":0">{{Cite book|url=https://books.google.com/books?id=SM3khPHXhKEC&q=stipule&pg=PA76|title=Plant Form: An Illustrated Guide to Flowering Plant Morphology|last=Bell|first=Adrian D.|date=2008-01-01|publisher=Timber Press|isbn=9780881928501|pages=74–79|language=en|access-date=2020-10-20|archive-date=2023-04-14|archive-url=https://web.archive.org/web/20230414083947/https://books.google.com/books?id=SM3khPHXhKEC&q=stipule&pg=PA76|url-status=live}}</ref>

== Types ==
=== According to duration ===
The three types of stipules according to duration are [[Dehiscence (botany)|caducous]], deciduous and persistent. Caducous stipules fall off before the leaf unfolds, while deciduous stipules fall off immediately after the leaf unfolds. Persistent stipules remain attached to the plant.<ref>{{Cite book|url=https://archive.org/details/botanysoutherns00darbgoog|quote=Caducous, Deciduous and Persistent stipules.|title=Botany of the Southern States|last=Darby|first=John|date=1860-01-01|publisher=A.S. Barnes & H.L. Burr|pages=[https://archive.org/details/botanysoutherns00darbgoog/page/n64 59]-61|language=en}}</ref>

=== According to shape, size and position ===
Stipules can be considered free lateral, adnate, interpetiolar, intrapetiolar, ochreate, foliaceous, bud scales, tendrillar or spiny.

A stipule can be fused to the stem, or to the other stipule from the same node.

A stipule is "adnate" if it's fused together on part of the petiole length, but the anterior is still free.

A stipule is "interpetiolar" if it is located in between the petioles, as opposed to being attached to the petioles, and generally one stipule from each leaf is fused together, so it appears that there's just one stipule between each leaf.<ref>{{Cite book|url=https://books.google.com/books?id=9HOmOElZL6IC&q=stipule&pg=PA33|title=How to Identify Trees in Southern Africa|last1=Wyk|first1=Braam Van|last2=Wyk|first2=Piet Van|date=2007-01-01|publisher=Struik|isbn=9781770072404|pages=33–36|language=en}}</ref>

A stipule is "intrapetiolar" if it is located in the angle that is between a stem and a petiole. In this case, the two stipules generally form together and appear to be one stipule.

A stipule is "ochreate" if a single stipule appears to be a solid tube that goes all the way around the stem.

A stipule is "foliaceous" if it is leaf-like. These are generally used to photosynthesize.

A stipule is considered a "bud scale" if it is hard or scaly and protects leaf buds as they form. These generally fall off as soon as the leaf unfolds.

A stipule is considered "tendrillar" if they are long thin tendrils, and are generally used by climbing plants.

A stipule is considered "spiny" if they are long and pointy. These are generally used to deter animals.

A stipule is considered to be "abaxial", "counter" or "leaf opposed" if it is located on the opposite side to where the leaf meets the stem.<ref name=":0" /><ref>{{Cite news|url=http://www.publishyourarticles.net/knowledge-hub/science/what-are-stipules-and-what-are-its-types/4494/|title=What are Stipules and what are its types ?|date=2012-02-14|work=PublishYourArticles.net - Publish Your Articles Now|access-date=2017-04-04|language=en-US|archive-date=2021-03-02|archive-url=https://web.archive.org/web/20210302180420/https://www.publishyourarticles.net/knowledge-hub/science/what-are-stipules-and-what-are-its-types/4494/|url-status=live}}</ref>

== Purpose of stipules ==
Stipules have various functions. Some stipules are not well understood or may be vestigial.

It is known that foliaceous stipules are used like leaves to make energy for the plants. Sometimes stipules protect the next leaf or bud as it grows in then falls off after the leaf unfolds, as with [[Liriodendron tulipifera|Tulip Poplars]].<ref name=":0" /> Stipules can be used as climbing tendrils by climbing plants. Spiny stipules can be used to help protect the plant from animals.<ref>{{Cite book|url=https://archive.org/details/b21931902|quote=stipule.|title=A Manual of Botany: Anatomical and Physiological for the Use of Students|last=Brown|first=Robert|date=1874-01-01|publisher=Blackwood|pages=[https://archive.org/details/b21931902/page/149 149]-152|language=en}}</ref>

== References ==
{{Reflist|30em}}

=== General references ===
* Esau, K. 1953. Plant Anatomy. Second Edition. John Wiley & Sons, Inc., New York, London, Sidney. 767 pp.

== External links ==
* [https://web.archive.org/web/20070208113718/http://www.botgard.ucla.edu/html/botanytextbooks/generalbotany/shootfeatures/generalstructure/stipules/index.html Stipules and stipels]

{{Commons category|Stipules}}
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[[Category:Leaf morphology]]