Identifying Evergreen Hybrids in the California Red Oaks

Al Keuter

Published May 2020 in International Oaks No. 31: 31–36

Abstract

While hybrids between the deciduous Quercus kelloggii and the three evergreen California Red Oaks have been described, hybrids between the evergreen species have not.

An ongoing study described here considers whether differences in acorn maturation time can provide insight into the identification of evergreen × evergreen hybrids.

Preliminary results of this study begun in 2017 are reported here.

Keywords

biennial acorn maturation, annual acorn maturation, Q. kelloggii, Q. agrifolia var. agrifolia, Q. agrifolia var. oxyadenia, Q. wislizeni, Q. parvula var. shrevei

References

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Keuter, A. 2017. The Red Oaks of the Bonny Doon Ecological Reserve, Status Report 3 –Morphology and Hybrids. Report provided to the California Department of Fish and Wildlife (unpublished).

Keuter, A., and P.S. Manos. 2019. Agrifoliae: the California Red Oaks. International Oaks 30: 191-208.

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