Betula populifolia

{{Short description|Species of birch}} {{Redirect|Grey birch|the moth|Aethalura punctulata}} {{Speciesbox | name = Gray birch | image = Gray birch against gray sky.jpg | image_caption = Gray birches in winter | genus = Betula | parent = Betula subg. Betula | species = populifolia | status = LC | status_system = IUCN3.1 | status_ref = <ref name=IUCN>{{cite iucn |last1=Stritch |first1=L. |year=2014 |title=''Betula populifolia'' |volume=2014 |article-number=e.T194635A2354478 |doi=10.2305/IUCN.UK.2014-3.RLTS.T194635A2354478.en |access-date=9 March 2026}}</ref> | status2 = G5 | status2_system = TNC | status2_ref = <ref name=NS>{{cite NatureServe |id=2.150177 |title=''Betula populifolia'' |access-date=9 March 2026}}</ref> | authority = [[Humphry Marshall|Marshall]] | range_map = Betula populifolia range map 2.png | range_map_caption = Natural range of ''Betula populifolia'' }}

'''''Betula populifolia''','' known as the '''gray''' (or '''grey) birch,''' is a [[deciduous]] [[tree]] in the family [[Betulaceae]]. It is native to eastern [[North America]] and is most commonly found in the northeast [[United States]] as well as southern [[Quebec]], [[New Brunswick]], and [[Nova Scotia]].<ref name=":2">{{Cite journal |last=Lavoie |first=Martin |last2=Pellerin |first2=Stéphanie |date=9 September 2015 |title=The palaeoecological record of gray birch (Betula populifolia) in eastern North America |url=https://doi.org/10.1139/cjb-2015-0140 |journal=Botany |volume=93 |issue=12 |pages=801–808}}</ref> The tree is a [[pioneer species]] that is commonly found in sites following disturbance, such as fire or logging.<ref name=":23">{{Cite web |title=Betula populifolia |url=https://www.fs.usda.gov/database/feis/plants/tree/betpop/all.html |access-date=2023-10-24 |website=www.fs.usda.gov}}</ref> Gray birches don't have as much economic value as other birch species but are still commonly used as ornamental trees.<ref name=":52">{{Cite web |last=Peronto |first=Marjories |last2=Manley |first2=Reeser C. |date=2008 |title=Bulletin #2567, Native Trees and Shrubs for Maine Landscapes: Gray Birch (Betula populifolia) |url=https://extension.umaine.edu/publications/2567e/ |access-date=2023-11-16 |website=UMaine Extension}}</ref>

== Description == ''Betula populifolia'' is a small tree that reaches heights of 20 to 30 feet (6 to 9 m) with a [[diameter at breast height]] (DBH) of 4 to 8 inches (10 to 20 cm). The tree is often found with multiple stems. The [[Crown (botany)|crown]] is pyramidal with somewhat drooping branches.<ref name=":0">{{Cite book |url=https://www.maine.gov/dacf/mfs/publications/handbooks_guides/forest_trees/pdf/Forest_Trees_of_Maine.pdf |title=Forest Trees of Maine |publisher=Maine Forest Service |year=2008 |isbn=9781882190614 |edition=14th |pages=92–93}}</ref><ref name=":1">{{Cite web |title=Virginia Tech Dendrology Fact Sheet |url=https://dendro.cnre.vt.edu/dendrology/syllabus/factsheet.cfm?ID=16 |access-date=2023-10-24 |website=dendro.cnre.vt.edu}}</ref>

The [[Bark (botany)|bark]] is smooth, a grayish-white or chalky color with visible [[lenticel]]s and black triangular patches located at the base of branches.<ref name=":23" /> It is commonly confused for paper birch (''[[Betula papyrifera]]'') by means of its bark, but it is differentiable as gray birch bark does not exfoliate (peel) as readily as paper birch. It is also occasionally confused for quaking aspen (''[[Populus tremuloides]]''), which has similar bark, but different leaves and buds.<ref name=":0" />

Twigs are slender, wiry, hairless, dull gray or brown in color, and have a warty or rough texture. [[Bud]]s are pointed, green-brown in color, shiny, and have a gummy coating.<ref name=":0" /> ''Betula populifolia'' lacks terminal buds. [[File:Betula populifolia leaves.jpg|thumb|The triangular leaves of ''Betula populifolia''. New Brunswick, Canada.]] The [[Leaf|leaves]] are 2.5 to 3 inches (5 to 7 cm) in length, alternate, simple, pinnately-veined, and taper to an elongated tip. They are dark green and glabrous above and paler below, with doubly serrate margins.<ref name=":1" /><ref>{{Cite book |last=Leopold |first=Donald J. |title=Harlow and Harrar's Textbook of Dendrology |last2=Hardin |first2=James W. |last3=White |first3=Fred M. |publisher=McGraw-Hill Education |year=2000 |isbn=9780073661711 |edition=9th}}</ref> Like other members of the [[Betula]] genus, leaves turn yellow in autumn. [[File:Betula populifolia bark.jpg|thumb|''Betula populifolia'' bark, with its signature black chevron patches.]] The [[flower]]s are wind-pollinated [[catkin]]s 2 to 3 inches (5 to 8 cm) long, the male catkins pendulous and the female catkins erect. The [[fruit]], maturing in autumn, is composed of many tiny winged seeds packed between the catkin bracts.<ref name=":1" />

=== Etymology === ''Betula populifolia'' means "birch with poplar-like leaves" when translated from Latin to English, and is derived from the behavior of gray birch leaves, which flutter similarly to poplar leaves in the wind.<ref name=":0" /><ref name=":6">{{Cite web |date=2017-12-05 |title=Gray Birch |url=https://www.bates.edu/canopy/species/gray-birch/ |access-date=2023-10-24 |website=Bates Canopy |language=en}}</ref>

== Distribution and habitat == Gray birch can be found in the northeast [[United States]] and small portions of [[Canada]]. It ranges from southeastern [[Quebec]] along the [[St. Lawrence River]] east to parts of [[New Brunswick]] and [[Nova Scotia]], south through [[New England]] and upstate [[New York (state)|New York]] to [[Pennsylvania]] and [[New Jersey]].<ref name=":2" /> There are also disjunct populations in [[Ohio]], western Pennsylvania, [[Virginia]], and [[North Carolina]].<ref name=":23" /> Gray birch has been listed as extinct in [[Delaware]], extirpated in [[Illinois]], and rare in Maryland.<ref name=":4">{{Cite web |last=Wennerberg |first=Sarah |date=May 31, 2006 |title=Plant Guide: Gray Birch |url=https://plants.usda.gov/DocumentLibrary/plantguide/pdf/pg_bepo.pdf |website=USDA Plants Database}}</ref>

The tree prefers well-drained, loamy soils, but can also grow in dryer, gravelly soils.<ref name=":4" /> They are tolerant of poor soils with low nutrient densities, which allows them to establish in a wide variety of habitats.<ref name=":52" /> They are known as [[pioneer species]] since they are often one of the first trees to populate a disturbed area, such as fields, burn sites, and abandoned mines.<ref name=":23" /><ref>{{Cite web |title=Betula populifolia Grey Birch PFAF Plant Database |url=https://pfaf.org/user/Plant.aspx?LatinName=Betula+populifolia |access-date=2023-11-17 |website=pfaf.org}}</ref> They thrive in sunlight since they are a [[Shade tolerance|shade intolerant]] species, but eventually give way to longer lived, more shade tolerant species. In regenerative stands, ''Betula populifolia'' are commonly found along other early successional species such as paper birch, quaking aspen, and bigtooth aspen (''[[Populus grandidentata]]'').<ref name=":52" /> In other mixed stands, gray birches are commonly associated with beech-birch-maple communities.<ref name=":23" />

=== Ecology === Gray birches play a role in the habitat of many different species of wildlife. A number of [[songbird]]s such as blue jays (''[[Blue jay|Cyanocitta cristata]]''), chickadees ''[[Black-capped chickadee|(Poecile atricapillus]]''), juncos (''[[Dark-eyed junco|Junco hyemalis]]''), and many others consume gray birch seeds.<ref name=":52" /> Moose ([[Moose|''Alces alces'']]), white-tailed deer (''[[White-tailed deer|Odocoileus virginianus]]''), and snowshoe hare (''[[Snowshoe hare|Lepus americanus]]'') use the twigs as browse, and although it's not their preferred feed, beavers (''[[North American beaver|Castor canadensis]]'') will chew the bark.<ref name=":4" />

Like other North American birches, gray birch is highly resistant to the bronze birch borer (''[[Agrilus anxius]]'').<ref>{{Cite journal |last=Nielsen |first=David G. |last2=Muilenburg |first2=Vanessa L. |last3=Herms |first3=Daniel A. |date=2011-06-01 |title=Interspecific Variation in Resistance of Asian, European, and North American Birches ( Betula spp.) to Bronze Birch Borer (Coleoptera: Buprestidae) |url=https://academic.oup.com/ee/article-lookup/doi/10.1603/EN10227 |journal=Environmental Entomology |language=en |volume=40 |issue=3 |pages=648–653 |doi=10.1603/EN10227 |issn=0046-225X|doi-access=free }}</ref> This is due to birches in North America sharing a coevolutionary relationship with the borer, allowing it to develop resistance to the bug. Despite this, the borers can still damage the trees if they are weakened by other means. Between about 1930 and 1950, many gray birch trees, along with paper birch and [[Betula alleghaniensis|yellow birch]] (''Betula alleghaniensis''), were weakened by [[Birch dieback|birch dieback disease]], which allowed for the bronze birch borer to attack and kill the trees.<ref name="Ciesla">{{cite book |author1=Ciesla, William M. |url=https://books.google.com/books?id=FDgYfi1G8L0C&pg=PA18 |title=Decline and Dieback of Trees and Forests: A Global Overview |author2=Donaubauer, Edwin |publisher=Food & Agriculture Org. |year=1994 |isbn=978-92-5-103502-3 |pages=18, 698}}</ref>

== Uses ==

=== Wood Products === Gray birch wood is soft and easily turned, so it is often made into spools, clothespins, and other turned woodenware. It is most commonly used as firewood. The wood is less sought after than paper birch due to its short lifespan, smaller size, and less common distribution. It also has tendencies to quickly deteriorate when exposed to excess moisture, meaning it has little commercial value beyond turned items and fuel.<ref name=":23" /><ref name=":6" />

=== Landscape Use === Gray birches are a commonly used landscape/ornamental tree. It is widely used due to its soil tolerance levels, resistance to bark borers, smaller stature, as well as the bark coloration. Whitespire is a common ornamental cultivar and has whiter bark than the natural form of the tree.<ref name=":52" /> Gray birch also can serve as a nurse tree for smaller, more economically valuable pines that require some form of protection to become established.<ref name=":4" />

=== Medicinal Use === Prior to the European colonists' arrival to North America, the indigenous [[Iroquois]] and [[Mi'kmaq]] peoples used the inner bark of gray birch trees to treat infected cuts and wounds.<ref name=":6" />

==References== {{Reflist|refs=  }}{{Commons}}

[[Category:Betula|populifolia]] [[Category:Trees of Northern America]] [[Category:Flora of Massachusetts]] [[Category:Trees of humid continental climate]] [[Category:Flora of Northern America]]