Oaks are in the genus Quercus which contains about 600 species. [2] Oaks are in the Beech family, Fagaceae which contain ten genera including Beeches (Fagus), Chestnuts (Castanea) and Oaks (Quercus). [4] Oaks are by far the best species of tree for attracting insects, butterflies and moths. [3]
The genus Quercus is divided into two groups, or subgenera: Leucobalanus (White Oaks) and Erythrobalanus (Red Oaks). [1] It’s a little confusing, because White Oaks is a subgenus of trees and a White Oak is also a species. The easiest way to determine whether an Oak is one of the White Oaks or Red Oaks is to look at the tip of a leaf. If, at the end of a lobe there is a tiny point called a bristle, it’s a Red Oak; otherwise it’s a White Oak. Identifying exactly which species requires more information.
White Oak – w/ no bristles [6]
- White Oak – Quercus alba
- Swamp Chestnut Oak or Basket Oak – Quercus michauxii
- Chestnut Oak – Quercus prinus
- Post Oak – Quercus stellata
Red Oaks are in the subgenus Erythrobalanus. This group has leaves with bristles at the tips of the lobes and the leaf apexes. The acorns require two growing seasons (biennial) to mature. [1] Red Oaks include:
- Scarlet Oak – Quercus coccinea
Southern Red Oak – w/ bristles [6]
- Southern Red Oak – Quercus falcata
- Laurel Oak – Quercus hemisphaerica
- Water Oak – Quercus nigra
- Willow Oak – Quercus phellos
- Northern Red Oak – Quercus rubra
- Shumard Oak – Quercus shumardii
- Live Oak – Quercus Virginiana
- Pin Oak – Quercus palustris
References and Additional Information
[1] UGA Extension: Native Plants for Georgia Part 1: Trees, Shrubs and Woody Vines (B987)
[2] Wikipedia: List of Quercus species
[3] Doug Tallamy: Bringing Nature Home – What to Plant
[4] Wikipedia: Fagaceae (Beech Family)
[5] South Carolina Forestry Commission: What Tree Is This? Lobed Simple Leaf
[6] USDA Forest Service: Field Guide to Native Oak Species of Eastern North America
the Intown Hawk 