People tend to use the terms white and red oaks as reference between two species, but this is actually not true (note that white oak is the species Quercus alba, and there is also a white oak group to which Quercus alba belongs). Oaks (which are in the Beech family-Fagaceae) are divided into two groups, the red and the white oaks. These groups each contain many different species that each have unique characteristics, while keeping some broad similarities with other species in their respective groups.
White Oaks
Oaks in the white oak group can be distinguished by smooth edges around the perimeter of their leaves, broad lobes on leaves (see the photo above), and scaly or shaggy appearing bark. The group includes trees such as the iconic white oak, swamp chestnut oak, post oak, and overcup oak. The nuts of white oaks vary in size and shape but are consumed more readily by deer and other critters because they contain less tannins than their counterparts, the red oaks. The fruits are high in carbohydrates and develop on branches in one growing season before falling, meaning that the flowers produced one spring will produce nuts that same fall.
Red Oaks
Red oak leaves have pointy prickles on the end of their leaf lobes (on the right in the top photo) and their bark is often very hard and tightly ridged with some light grey stripes running vertically up the trunk. Some notable oaks in this group include willow oak, pin oak, southern red oak, northern red oak, and scarlet oak. Some red oak acorns are very small, providing a valuable food source for smaller species like wood ducks. Neither red or white oak acorns contain much protein, but red oak acorns contain high amounts of fat and tannin, making them bitter and slower to be eaten by deer compared to white oaks. They take two years to mature on the branch, so the nuts produced by flowers this spring (2018) will not ripen and fall until the autumn of 2019.
Conclusions
I hope that this brief overview of the red oak and white oak groups has familiarize you with some of the terminology on these valuable wildlife trees. Oaks are prolific fruit producers in fall and can provide an abundance of hard mast for wildlife depending on the year. Therefore, being familiar with the wide variety of oak species is beneficial to hunting strategy and makes you a more well-rounded habitat steward. Happy hunting this fall, and hopefully one of these trees will pull in a deer for you!
Loved your summary of the difference between red and white oaks – thank you – so clear.