A Tale of Two Lonely Oaks: Quercus acerifolia and Q. humboldtii

Yingtong “Amanda” Wu

Published May 2022 in International Oaks No. 33: 15–26

Abstract

The genus Quercus is widespread throughout the Northern Hemisphere and, at the same time, includes a high number of endemic species. Understanding and protecting these “lonely oaks” should be a part of oak conservation efforts.

Herein I share two research stories, the first about Q. acerifolia, a temperate, deciduous oak, endemic to the Ozark Mountains (USA), and the second, Q. humboldtii, a cloud-forest, evergreen oak, restricted to the Colombian Andes.

For Q. acerifolia, morphometric analyses to determine species delimitation confirm that this taxon is an Ozark endemic with unique morphological features. For Q. humboldtii, herbivory rates in relation to tree age and branch height were studied to test whether older trees suffer from higher leaf herbivory rates. Though no relationship between tree age and herbivory rates was found, a negative relationship between branch height and herbivory rates was.

The different threats faced by these two endemic, “lonely” oaks, are discussed, as are directions for future investigation.

Keywords

endemic  species,  species  delimitation,  morphometric  analyses,  canopy ecology, mother trees, herbivory rates

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