Editing Quercus palustris (section)

==Description==
[[File:Pin Oak Northampton MA - August 2013.jpg|thumb|Largest known pin oak in New England, located in [[Northampton, Massachusetts]]. 2005 measurements: Height {{convert|107.9|ft|m|order=flip}}, circumference {{convert|17.4|ft|m|order=flip}}, average spread {{convert|96|ft|m|order=flip}}]]

Quercus palustris is a medium-sized [[deciduous]] tree growing to {{convert|18|-|22|m|ft|abbr=off}} tall, with a trunk up to {{convert|1|m|ft|abbr=on|frac=2}} in diameter. It has an {{convert|8|-|14|m|ft|adj=on|abbr=on}} spread. A 10-year-old tree grown in full sun will be about {{convert|8|m|ft|abbr=on}} tall. Young trees have a straight, columnar trunk with smooth bark and a pyramidal canopy.

By the time the tree is 40 years old, it develops more rough [[Bark (botany)|bark]] with a loose, spreading canopy. This canopy is considered one of the most distinctive features of the pin oak: the upper branches point upwards, the middle branches are at right angles to the trunk, and the lower branches droop downwards.<ref name="USDA"/><ref name=FNA>{{eFloras|1 |family=Fagaceae |first=Kevin C. |last=Nixon}}</ref>

The [[leaves]] are {{convert|5|-|16|cm|frac=4|abbr=off}} long and {{convert|5|-|12|cm|frac=4|abbr=on}} broad, lobed, with five or seven lobes. Each lobe has five to seven bristle-tipped teeth. The [[Sinus (botany)|sinuses]] are typically U-shaped and extremely deep cut. In fact, roughly the same amount of sinus area exists as actual leaf area. The leaf is mostly hairless, except for a very characteristic tuft of pale orange-brown down on the lower surface where each lobe vein joins the central vein. Overall autumn leaf coloration is generally bronze, though individual leaves may be red for a time, and is not considered particularly distinctive.<ref name="Arbor">"Oak, Pin Quercus palustris", http://www.arborday.org/treeguide/TreeDetail.cfm?id=19</ref> The [[acorn]]s, borne in a shallow, thin cap, are hemispherical, {{convert|10|-|16|mm|frac=32}} long and {{convert|9|-|15|mm|frac=32|abbr=on}} broad, green maturing pale brown about 18 months after [[pollination]].<ref name=FNA/> Unless processed using traditional methods, the acorn is unpalatable because the kernel is very bitter.{{citation needed|date=February 2021}}

In its natural environment pin oak is a relatively short-lived, fast-growing pioneer or riparian species with a lifespan of approximately 120 years against many oaks which can live several centuries. Despite this there are many examples of pin oak that exceed this lifespan.<ref>{{cite web |url=https://www.monumentaltrees.com/en/trees/quercuspalustris/records/ |title=The thickest, tallest, and oldest pin oak trees (Quercus palustris) |website=www.monumentaltrees.com |access-date=2021-09-08}}</ref> It develops a shallow, fibrous [[root]] system, unlike many [[oak]]s, which have a strong, deep taproot when young.<ref name="USDA"/>

A characteristic shared by a few other oak species, and also some beeches and hornbeams, is the retention of leaves through the winter on juvenile trees, a natural phenomenon referred to as [[marcescence]]. Young trees under {{convert|6|m|ft|abbr=on}} are often covered with leaves year-round, though the leaves die in the fall, remaining attached to the shoots until the new leaves appear in the spring. As with many other oak species, dead pin oak branches  stay on the tree for many years.<ref name="USDA"/><ref name=FNA/>

=== Flowering and fruiting ===
Like all oaks, flowering and leaf-out occur in late spring when all frost danger has passed. The flowers are monoecious catkins which, being self-incompatible, require the presence of another oak for pollination. Any species in the red oak group can serve as a pollinator, but in pin oak's natural range, this will usually be [[northern red oak]] or [[scarlet oak]]. Interspecies hybridization occurs freely. The acorns require two growing seasons to develop.<ref name="FNA" />

{{gallery|mode=packed
|File:Bark Quercus palustris.jpg|Bark
|File:Quercus-palustris.JPG|Leaves
|File:2016-04-15 15 31 48 Pin Oak catkins at Franklin Farm Park in the Franklin Farm section of Oak Hill, Fairfax County, Virginia.jpg|Catkins of pin oak
|File:2014-11-02 11 29 54 Pin Oak during autumn along Lower Ferry Road in Ewing, New Jersey.JPG|Mature pin oak displaying typical bronze autumn coloration
|File:2014-10-30 10 02 06 Pin Oak foliage during autumn along Dunmore Avenue in Ewing, New Jersey.JPG|Typical autumn foliage
|File:Moeraseik (Quercus palustris), 29-04-2024 (d.j.b.).jpg|Emerging young shoots. 
}}