Editing Pine (section)

== Description ==

Pine trees are [[evergreen]], coniferous [[resin]]ous [[tree]]s (or, rarely, [[shrub]]s) growing {{convert |3 |– |80 |m |ft |abbr=off |-1}} tall, with the majority of species reaching {{convert |15 |– |45 |m |ft |abbr=on |-1}} tall.<ref name="Mail Tribune">{{Cite news |url=http://www.mailtribune.com/apps/pbcs.dll/article?AID=/20110123/NEWS/101230353/ |title=Tallest of the tall |last=Fattig |first=Paul |date=23 January 2011 |newspaper=Mail Tribune |location=Medford, Oregon |access-date=27 January 2011 |url-status=dead |archive-url=https://web.archive.org/web/20120923095326/http://www.mailtribune.com/apps/pbcs.dll/article?AID=%2F20110123%2FNEWS%2F101230353%2F |archive-date=23 September 2012 }}</ref> The smallest are [[Siberian dwarf pine]] and [[Potosi pinyon]], and the tallest is an {{convert |83.45 |m |abbr=on}} tall [[sugar pine]] located in [[Yosemite National Park]].<ref>{{cite news | title = 3 Sierra sugar pines added to list of 6 biggest in world | newspaper = Associated Press | location = South Lake Tahoe, California | language = English | date = 31 Jan 2021| url = https://apnews.com/article/nevada-forests-south-lake-tahoe-17501dc8cb094fc7ffb1543426631bc6 | access-date = 13 Feb 2023}}</ref>

Pines are long lived and typically reach ages of 100–1,000 years, some even more. The longest-lived is the [[Great Basin bristlecone pine]] (''P.&nbsp;longaeva''). One individual of this species, dubbed "[[Methuselah (pine tree)|Methuselah]]", is one of the [[List of longest-living organisms|world's oldest living organisms]] at around 4,800-years old. This tree can be found in the [[White Mountains (California)|White Mountains]] of California.<ref>{{cite journal |last1=Ryan |first1=Michael |last2=Richardson |first2=David M. |title=The Complete Pine |journal=BioScience |date=December 1999 |volume=49 |issue=12 |pages=1023–1024 |doi=10.2307/1313736 |jstor=1313736}}</ref> An older tree, now cut down, was dated at 4,900-years old.<ref>{{cite news |last=Miranda |first=Carolina A. |date=28 February 2015 |title=Follow-up: More tales of the Prometheus tree and how it died |url=https://www.latimes.com/entertainment/arts/miranda/la-et-cam-video-prometheus-bristlecone-pine-20150227-column.html  |newspaper=[[Los Angeles Times]] |access-date=16 October 2020}}</ref><ref name="Eveleth">{{Cite magazine |last=Eveleth |first=Rose |author-link=Rose Eveleth |date=15 November 2012 |title=How One Man Accidentally Killed the Oldest Tree Ever |url=https://www.smithsonianmag.com/smart-news/how-one-man-accidentally-killed-the-oldest-tree-ever-125764872/ |magazine=Smithsonian |publisher=[[Smithsonian Institution]] |access-date=16 October 2020}}</ref> It was discovered in a grove beneath [[Wheeler Peak (Nevada)|Wheeler Peak]] and it is now known as "[[Prometheus (tree)|Prometheus]]" after the [[Prometheus|Greek immortal]].<ref name="Eveleth"/>

The spiral growth of branches, needles, and [[Conifer cone|cones]] scales [[Phyllotaxis|are arranged]] in [[Fibonacci number]] ratios.<ref>{{cite journal |last1=Zeng |first1=Lanling |last2=Wang |first2=Guozhao |title=Modeling golden section in plants |journal=Progress in Natural Science |year=2009 |volume=19 |issue=2 |pages=255–260 |doi=10.1016/j.pnsc.2008.07.004 |quote=The ratio between two pine needles is 0.618 [...] the angle between the two neighbors is about 135° and the angle between the main stem and each branch is close to 34.4° which is the golden section of 90° |doi-access=free|bibcode=2009PNSMI..19..255Z }}</ref><ref>{{cite web |url=https://trees.stanford.edu/ENCYC/PINUSnotes.htm |title=Pinus (Pine) Notes |last1=Bracewell |first1=Ronald |last2=Rawlings |first2=John |website=Trees of Stanford |access-date=2 February 2020}}</ref>

<gallery class=center mode=nolines widths=180 heights=180>
File:Big bristlecone pine Pinus longaeva.jpg|Ancient ''[[Pinus longaeva]]'', [[California]]
File:Tree Types and Barks 004.jpg|''[[Pinus taeda]]'' bark
File:Pine needles.png|Pine needles
File:Pinus radiata cone.jpg|''[[Pinus radiata]]'' female cone
</gallery>

=== Bark ===

The [[Bark (botany)|bark]] of most pines is thick and scaly, but some species have thin, flaky bark. The branches are produced in "pseudo-whorls", actually a very tight spiral but appearing like a ring of branches arising from the same point. Many pines are uninodal, producing just one such whorl of branches each year, from [[bud]]s at the tip of the year's new [[plant stem|shoot]], but others are multinodal, producing two or more whorls of branches per year.<ref name="RHSD">{{cite book | title=Royal Horticultural Society Dictionary of Gardening | publisher=Macmillan Press ; Stockton Press | publication-place=London : New York | date=1992 | isbn=1-56159-001-0 |volume=3 | pages=582–594}}</ref>

=== Foliage ===

Pines have four types of [[leaf]]:

* Seed leaves ([[cotyledon]]s) on seedlings are borne in a whorl of 4–24.
* Juvenile leaves, which follow immediately on seedlings and young plants, are {{Convert |2–6 |cm |abbr=off |frac=4}} long, single, green or often blue-green, and arranged spirally on the shoot. These are produced for six months to five years, rarely longer.
* Scale leaves, similar to bud scales, are small, brown and not photosynthetic, and arranged spirally like the juvenile leaves.
* Needles, the adult leaves, are green ([[photosynthetic]]) and bundled in clusters called [[Fascicle (botany)|fascicles]]. The needles can number from one to seven per fascicle, but generally number from two to five. Each fascicle is produced from a small bud on a dwarf shoot in the axil of a scale leaf. These bud scales often remain on the fascicle as a basal sheath. The needles persist for 1.5–40 years, depending on species. If a shoot's [[apical meristem|growing tip]] is damaged (e.g. eaten by an animal), the needle fascicles just below the damage will generate a stem-producing bud, which can then replace the lost growth tip.<ref name="RHSD"/>

=== Cones ===

Pines are [[monoecious]], having the male and female cones on the same tree.<ref name=Judetal>{{cite book |first1=W.S. |last1=Judd |first2=C.S. |last2=Campbell |first3=E.A. |last3=Kellogg |first4=P.F. |last4=Stevens |first5=M.J. |last5=Donoghue |date=2002 |title=Plant systematics, a phylogenetic approach |edition=2 |publisher=Sinauer Associates |isbn=0-87893-403-0 }}</ref>{{rp |205}} The male cones are small, typically 1–5&nbsp;cm long, and only present for a short period (usually in spring, though autumn in a few pines), falling as soon as they have shed their [[pollen]]. The female cones take 1.5–3 years (depending on species) to mature after [[pollination]], with actual fertilisation delayed one year. At maturity the female cones are 3–60&nbsp;cm long. Each cone has numerous spirally arranged scales, with two seeds on each fertile scale; the scales at the base and tip of the cone are small and sterile, without seeds.<ref name="RHSD"/>

The seeds are mostly small and winged, and are [[Anemochory|anemochorous]] (wind-dispersed), but some are larger and have only a vestigial wing, and are [[bird]]-dispersed. Female cones are woody and sometimes armed to protect developing seeds from foragers. At maturity, the cones usually open to release the seeds. In some of the bird-dispersed species, for example [[whitebark pine]],<ref>{{Cite journal |last=Tomback |first=Diana F. |author-link=Diana Tomback |date=June 1982 |title=Dispersal of Whitebark Pine seeds by Clark's Nutcracker: a mutualism hypothesis |journal=The Journal of Animal Ecology |volume=51 |issue=2 |pages=451–467 |doi=10.2307/3976 |jstor=3976 |bibcode=1982JAnEc..51..451T }}</ref> the seeds are only released by the bird breaking the cones open. In others, the seeds are stored in closed cones for many years until an environmental cue triggers the cones to open, releasing the seeds. This is called [[serotiny]]. The most common form of serotiny is pyriscence, in which resin binds the cones shut until melted by a forest fire, for example in ''[[Pinus radiata|P.&nbsp;radiata]]'' and ''[[Pinus muricata|P.&nbsp;muricata]]''; the seeds are then released after the fire to colonise the burnt ground with minimal competition from other plants.<ref name="RHSD"/><ref name="Rushforth">{{cite book | last=Rushforth | first=Keith | title=Conifers | publisher=Christopher Helm Publishers, Incorporated | publication-place=London | date=1987-01-01 | isbn=0-7470-2801-X | pages=158–192}}</ref>