Oaks (Quercus) like the Plateau live oak (Q. fusiformisSmall) (photographed above)and post oak (Q. stellataWangeh. (photographed on the next page) are common trees of the uplands surrounding the Colorado River.

Plateau live and postoaks belong to the Fagaceae or beech family, which contains about nine genera and 600-800 species. Species names consist of three parts, the genus (Quercus), species name (Q. fusiformis or Q. stellata), and authority (for example, John Kunkel Small, the botanist that named Q fusiformis). The genus Quercusis from the classical Latin name used by the Romans for the English oak and the family contains about 400 species. The live oak species name, Q. fusiformis, was chosen by Small when he named the species because of the spindle shaped nut or acorn, which can be described as fusiform. The common name Plateau live oak, refers to the region in Texas where it is often found as well as it being an evergreen. The post oak species name, Q. stellata, refers to star-shaped plant hairs that occur on the surface of the leaf. It is the most common oak in Texas and its common name probably derives from its use in fences.

Plateau live and postoaks produce tiny male flowers in drooping clusters called catkins and have tiny, pencil-lead sized female flowers (photographed above in close-ups under the tree photographs) surrounded by bracts that eventually form the cup that contains the mature fruit commonly called an acorn. The pollen from catkins can cause allergies and acorns are often planted by squirrels that cache the fruits and forget their locations. Plateau live oaks can be killed by a disease called oak wilt, which has become common in our region. The disease is caused by a species of fungus that spreads from tree to tree through connected roots and in some cases by beetles. It can also be spread from tree to tree using trimming implements. The fungus basically clogs up the water transporting tissues of the trees and they die.

The acorns provide mast for wildlife such as deer and squirrels. Domestic livestock also eat oaks. Oaks contain high amounts of tannic acid that can poison animals. Diets of less than 50% oak foliage and acorns is considered safe for animals.

Native Americans also ate the acorns ground into a meal. To remove the harmful tannins, they soaked the acorns in baskets in clean, flowing streams. You can also boil them in a pot with plenty of water for about 15 minutes and pour off the brown water. Repeat this for two or three hours or until the water quits turning brown. Then roast them at about 200˚F for an hour. The Kiowa tribe pounded acorns to make meal for mush and baking as well as to produce a coffee-like drink. Before the corn feeders used by modern hunters in Texas, mast from oak forest was the primary source of food for wild animals that were hunted by Native Americans.

Sources:

Diggs, G. M., B. L. Lipscomb, and R. J. O’Kennon. 1999. Shinners & Mahler’s Illustrated Flora of North Central Texas. Botanical Research Institute of Texas. Fort Worth, Texas.

Tull, D. 2013. Edible and useful plants of the southwest: TX, NM and AZ. Austin: University of Texas Press.

Turner, M. W. 2009. Remarkable Plants of Texas: Uncommon Accounts of Our Common Natives. Austin: University of Texas Press.

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