From Manitoba to Texas: A study of the population genetic structure of bur oak (Quercus macrocarpa)

In the taxonomic world, the oaks are known as a rambunctious group, notorious for hybridizing. In this report, we present preliminary information to address the question of how much hybridization is occurring between bur oak and white oaks with which it is sympatric, through rangewide sampling of bur oak and five co-occurring species: white oak (Q. alba L.), swamp white oak (Q. bicolor Willd.), post oak (Q. stellata Wangenh.), chinkapin oak (Q. muehlenbergii Engelm.), and overcup oak (Q. lyrata Walter). Bur oak is known to hybridize with all of these species (Hardin 1975). Using our multilocus dataset, we find that despite apparent introgression, these oak species are genetically cohesive.