Ten Corylus species compared through exact Wikimedia Commons photographs of leaves, fruit and growth forms. An editorial selection, not a scientific ranking. Original video contributions: CC BY-SA 4.0. Individual photographs retain the licences and credits listed in attribution; public-domain and CC0 photographs remain so. Photograph credits: 1. File:20170712Corylus avellana1.jpg; AnRo0002; CC0; http://creativecommons.org/publicdomain/zero/1.0/deed.en; https://commons.wikimedia.org/wiki/File:20170712Corylus_avellana1.jpg; Central portrait crop and scaling; title and caption bars added. Photograph licensed under the stated source licence. 2. File:Hasel fg01.jpg; Fritz Geller-Grimm; CC BY-SA 2.5; https://creativecommons.org/licenses/by-sa/2.5; https://commons.wikimedia.org/wiki/File:Hasel_fg01.jpg; Central portrait crop and scaling; title and caption bars added. Photograph licensed under the stated source licence. 3. File:Corylus colurna subadriatic dinaric mountains Orjen.JPG; Orjen, Pavle Cikovac; CC BY-SA 3.0; https://creativecommons.org/licenses/by-sa/3.0; https://commons.wikimedia.org/wiki/File:Corylus_colurna_subadriatic_dinaric_mountains_Orjen.JPG; Central portrait crop and scaling; title and caption bars added. Photograph licensed under the stated source licence. 4. File:Corylus americana1.jpg; U.S. Fish and Wildlife Service (individual photographer unspecified); Public domain; https://commons.wikimedia.org/wiki/File:Corylus_americana1.jpg#Licensing; https://commons.wikimedia.org/wiki/File:Corylus_americana1.jpg; Central portrait crop and scaling; title and caption bars added. Photograph licensed under the stated source licence. 5. File:Corylus cornuta 15-p.bot-coryl.cornu-15.jpg; Ayotte, Gilles, 1948-; CC BY-SA 4.0; https://creativecommons.org/licenses/by-sa/4.0; https://commons.wikimedia.org/wiki/File:Corylus_cornuta_15-p.bot-coryl.cornu-15.jpg; Central portrait crop and scaling; title and caption bars added. Photograph licensed under the stated source licence. 6. File:Corylus heterophylla.JPG; Dalgial; CC BY-SA 3.0; https://creativecommons.org/licenses/by-sa/3.0; https://commons.wikimedia.org/wiki/File:Corylus_heterophylla.JPG; Central portrait crop and scaling; title and caption bars added. Photograph licensed under the stated source licence. 7. File:Corylus sieboldiana 4.JPG; Qwert1234; CC BY-SA 3.0; https://creativecommons.org/licenses/by-sa/3.0; https://commons.wikimedia.org/wiki/File:Corylus_sieboldiana_4.JPG; Central portrait crop and scaling; title and caption bars added. Photograph licensed under the stated source licence. 8. File:Corylus ferox.jpg; Natacha Frachon; CC BY 3.0; https://creativecommons.org/licenses/by/3.0; https://commons.wikimedia.org/wiki/File:Corylus_ferox.jpg; Central portrait crop and scaling; title and caption bars added. Photograph licensed under the stated source licence. 9. File:Corylus chinensis kz01.jpg; Krzysztof Ziarnek, Kenraiz; CC BY-SA 4.0; https://creativecommons.org/licenses/by-sa/4.0; https://commons.wikimedia.org/wiki/File:Corylus_chinensis_kz01.jpg; Central portrait crop and scaling; title and caption bars added. Photograph licensed under the stated source licence. 10. File:Corylus jacquemontii (7788844336).jpg; Dinesh Valke from Thane, India; CC BY-SA 2.0; https://creativecommons.org/licenses/by-sa/2.0; https://commons.wikimedia.org/wiki/File:Corylus_jacquemontii_(7788844336).jpg; Central portrait crop and scaling; title and caption bars added. Photograph licensed under the stated source licence.