Contributed by Katherine Wagner-Reiss

The Morris Arboretum Catalogue of Plants in the Living Collection is an amazing online resource; many thanks to Elinor I. Goff, Plant Recorder. I count 530 Quercus   on the list, Quercus being the Latin name for the oak genus. Letʻs talk about those oaks at Morris Arboretum whose species names mention their color: Quercus alba (white oak), Quercus bicolor (swamp white oak), Quercus coccinea (scarlet oak), Quercus nigra (water oak), and Quercus rubra (northern red oak).


Quercus alba (white oak) with whitish bark. Photo by Katherine Wagner-Reiss.

Alba means white and Quercus alba is named for its whitish bark. It is the state tree of three states: Connecticut, Illinois, and Maryland (second only to the sugar maple, which is the state tree of four states)!

 


Quercus bicolor (swamp white oak) with two-toned bark. Photo by Katherine Wagner-Reiss.

Bicolor means two-colored and the bark on the branches of Quercus bicolor exfoliates so that the lighter inner bark is exposed, thus the specific epithet “bicolor.” It is the only oak with this feature. The common name “swamp white oak” gives additional useful information that this tree is found in swampy habitats.

 


Quercus coccinea with scarlet fall leaves. Photo by Famartin on Wikimedia Commons.

Coccinea means scarlet, and, while the leaves are green in the summer, the tree is named for its scarlet autumn leaves. It is the state tree of Washington, D.C.

 


Quercus nigra with blackish acorns. Photo by Robert H. Mohlenbrock, hosted by the USDA-NRCS PLANTS Database/USDA SCS.1991.

Nigra means black because the acorns of Quercus nigra are blackish or very dark.  The fallen acorns can stain concrete for months in the fall and winter. The common name  “water oak “ reveals that this is a bottomland tree, often found along streams.

 


Quercus rubra with red heartwood. Photo used with the permission of Dr.Elisabeth Wheeler of NC State University.

Rubra means red and Quercus rubra is named for its red heartwood. It is the state tree of New Jersey.

All of these color features are easily seen in the autumn, so I encourage you to look for them.

And now for a mind-teaser: What is the meaning of the capital of New Mexico?

Yes, Albuquerque means white oak!

 

Katherine has her Certificate in Botany from the New York Botanical Garden and is a botanical tour guide and free-lance writer.