Tree of the Week Double Feature: Southern Red Oak (Quercus falcata) and Black Oak (Quercus velutina)

Last week we studied a green ash (Fraxinus pennsylvanica) that has grown and developed in a minimally competitive environment. The reduced competition has resulted in a very nice looking specimen, with a straight, strong trunk and uniformly oval crown. Since the tree stands alone, we are able to appreciate its overall form. You can find that post here.

This week, we have an interesting study of two oaks that have grown in direct competition with one another. The black oak (Quercus velutina) was planted first. In November 1995, this individual was collected as a seedling from the Caroline Dormon Nature Preserve (Bienville Parish). The following January it was planted in the ground of the arboretum, in its present location. Sometime later, a southern red oak (Quercus falcata) germinated in the same spot. One of the two is clearly the better competitor.

Pictured above, we have two different red oak species growing in the same spot. The skinny, leaning trunk belongs to the black oak, which is the older of the two. This tree was planted first with careful consideration. The southern red oak trunk is straight and significantly thicker. The precise age of the southern red oak is unknown, but we know that it is younger than the black oak and it has been in the catalogue since 2004.

Since the two trees have grown together, it's difficult to say much about the overall form of either specimen. For the most part, it appears that the southern red oak has suffered very little from cohabitation: the trunk is straight and the crown is nicely rounded at the top. However, if the black oak were completely removed, we might find that the southern red oak has a lopsided development. For the time being, this is a great spot to compare two different kinds of red oak leaves!

The upper surface of the southern red oak leaf is dark-green and smooth. This species is known for variability of leaf-shape, but all leaves are lobed with bristle-tips. This leaf measures more than 8 inches in length; the petiole measures a little less than 2 inches.

Underneath, southern red oak leaves are a dull brownish-green.

Southern red oak leaves are also fuzzy underneath. They are soft to the touch, rather than waxy like the upper surface.

This is a black oak leaf. It has a dark-green, smooth upper surface, and its shallow lobes are bristle-tipped. Its shape is clearly different from the deeply-lobed southern red oak leaf pictured above. However, keep in mind that, like the southern red oak, black oak leaves vary in shape, too. You can see some of this variety in a post about a different black oak, found here.

Underneath, black oak leaves are lighter in color and very soft to the touch.

The leaves on this black oak feel like velvet underneath, significantly softer than the leaves of the southern red oak.