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Plant Focus

Quercus macdougallii
A rare oak endemic to the Sierra Juárez in Oaxaca

Should Hybridization Make Us Skeptical of the Oak Phylogeny?

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Andrew Hipp

Published May 2015 in International Oaks No. 26: 9–17.


Quercus macrocarpa in fact, looks and acts very much like any good species; the only criterion in which Q. macrocarpa fails as a modern concept is in the area of gene flow.” Burger 1975, Taxon 24

“It may well be that Quercus macrocarpa in Quebec exchanges many more genes with local Q. bicolor than it does with Q. macrocarpa in Texas.” Van Valen 1976, Taxon 25

“All [eastern North American white oak] species have maintained their distinctiveness in face of this local ‘contamination,’ and I see no justification for considering the entities anything less than good taxonomic species.” Hardin 1975, Journal of the Arnold Arboretum


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