Editing Oak (section)

=== Fossil history ===

Potential records of ''Quercus'' have been reported from [[Late Cretaceous]] deposits in North America and East Asia. These are not considered definitive, as macrofossils older than the [[Paleogene]], and possibly from before the [[Eocene]] are mostly poorly preserved without critical features for certain identification. Amongst the oldest unequivocal records of ''Quercus'' are pollen from Austria, dating to the [[Paleocene]]-Eocene boundary, around 55 million years ago. The oldest records of ''Quercus'' in North America are from [[Oregon]], dating to the Middle Eocene, around 44 million years ago, with the oldest records in Asia from the Middle Eocene of Japan; both forms have affinities to the ''[[Cyclobalanopsis]]'' group.<ref>{{Citation |last1=Barrón |first1=Eduardo |title=The Fossil History of ''Quercus'' |date=2017 |work=Oaks Physiological Ecology. Exploring the Functional Diversity of Genus Quercus L. |volume=7 |pages=39–105 |editor-last=Gil-Pelegrín |editor-first=Eustaquio |place=Cham |publisher=Springer International Publishing |doi=10.1007/978-3-319-69099-5_3 |isbn=978-3-319-69098-8 |last2=Averyanova |first2=Anna |last3=Kvaček |first3=Zlatko |last4=Momohara |first4=Arata |last5=Pigg |first5=Kathleen B. |last6=Popova |first6=Svetlana |last7=Postigo-Mijarra |first7=José María |last8=Tiffney |first8=Bruce H. |last9=Utescher |first9=Torsten |display-authors=3 |series=Tree Physiology |hdl=10261/277765 |editor2-last=Peguero-Pina |editor2-first=José Javier |editor3-last=Sancho-Knapik |editor3-first=Domingo |hdl-access=free }}</ref>

<gallery class=center mode=nolines widths=200px heights=200px>
File:Quercus hispanica 20170317.jpg|''[[Quercus × hispanica]]'' leaf. [[Miocene]], [[Lleida]], Spain
File:Quercus hiholensis acorn UWBM 56470-3 Pigg & Wehr 2002 Plt2 fig16.png|''[[Quercus hiholensis]]'' acorn, [[Langhian]] age (Middle Miocene), Washington State, US (c. 15 mya)
File:Quercus kobatakei leaf (cropped).jpg|''Quercus kobatakei'' leaf. Early [[Oligocene]], Japan
File:Early Oligocene oak acorn from Bridge Creek Flora.jpg|Early Oligocene acorn, Oregon, US (33 mya)
</gallery>