Editing Quercus macrocarpa (section)

==Description==
''Quercus macrocarpa'' is a large [[deciduous]] [[tree]] growing up to {{convert|30|m|abbr=off}}, rarely {{cvt|50|m}}, in height,<ref name="FNA">{{eFloras|1|233501058|Quercus macrocarpa |family=Fagaceae|first=Kevin C. |last=Nixon}}</ref> and is one of the most massive oaks with a trunk diameter of up to {{cvt|10|ft|0|order=flip}}. It is one of the slowest-growing oaks, with a growth rate of {{convert|12|in|cm|0|order=flip}} per year when young. However, one source states that a well-established tree can grow up to {{cvt|20|in|cm|order=flip}} per year.<ref name="Houser 2013">{{cite web |last1=Houser |first1=Steve |title=Tree Species Profiles: Top Rated Shade Trees, Bur Oak (Quercus macrocarpa) |url=https://www.arborilogical.com/articles/all-articles/article-repository/2013/april/tree-species-profiles-top-rated-shade-trees-bur-oak-quercus-macrocarpa/ |publisher=Arborilogical Services, Inc. |location=Wylie, Texas |date=19 April 2013}}</ref>{{Unreliable source?|date=December 2022}} A 20-year-old tree will be about {{cvt|60|ft|m|0|order=flip}} tall if grown in full sun.{{citation needed|date=August 2021}} Naturally occurring saplings in forests will typically be older. Bur oaks commonly live to be 200 to 300 years old, and may live up to 400 years.<ref>{{cite web |title=Quercus macrocarpa |url=http://www.ldeo.columbia.edu/~adk/oldlisteast/Spp/QUMAC.html |website=Eastern OLDLIST |year=2010 |publisher=Rocky Mountain Tree-Ring Research, Inc. and Eastern Kentucky University}}</ref> The [[Bark (botany)|bark]] is gray with distinct vertical ridges.<ref name="FNA" />

The [[leaves]] are {{cvt|7|–|15|cm|in|frac=4}} long and {{cvt|5|–|13|cm|in|frac=4}} broad, variable in shape, with a lobed margin. Most often, the basal two-thirds is narrower and deeply lobed, while the apical third is wider and has shallow lobes or large teeth. They usually do not show strong fall color, although fine golden hues are occasionally seen.{{r|Houser 2013}} The [[flower]]s are greenish-yellow [[catkin]]s, produced in the spring. The [[acorn]]s are very large, {{cvt|2.5|–|5|cm|in|frac=4}} long and {{cvt|2|-|4|cm|in|frac=4}} broad, having a large cup that wraps much of the way around the nut, with large overlapping scales and often a fringe at the edge of the cup.<ref name="FNA" />

The wood when sawn transversely shows the characteristic annual rings formed by [[Secondary growth|secondary thickening]].

Bur oak is sometimes confused with other members of the white oak section, such as ''[[Quercus bicolor]]'' (swamp white oak),{{r|gobot}} ''[[Quercus lyrata]]'' (overcup oak), and ''[[Quercus alba]]'' (white oak). It [[Hybrid (biology)|hybridises]] with several other species of oaks.

{{Gallery
|Bur Oak Winter Form.jpg|Spreading branches
|Quercus macrocarpa USDA.jpg|Leaves and acorn
|Quercus macrocarpa-Acorn R 51 g edit (24212435556).jpg|Acorns
|QuercusMacrocarpa.jpg|Bark
}}