Quercus turbinella
Aka: the Sonoran Scrub Oak
Quercus turbinella or more commonly known as the Sonoran scrub oak, Grey oak, or shrub live oak is found in the southwestern United States and parts of northern Mexico. It is a perennial evergreen and a flowering dicot belonging to the Fagaceae or Beech family and can grow to 15 feet (~5 meters) making it a shrub and/or a tree. They live near desert borders, regions described as chaparral, or pinyon-juniper woodlands between 800 to 2000 meters elevation. One possible derivation for the word "Quercus" (the genus name commonly referred to as oaks) is that it may have come from the Celtic word quer "fine" and cuez "tree", thus an oak or quercus is a skinny tree. The word "turbinella" means shaped like a spinning top and describes the acorns. As there are nearly 200 accepted species and over 200 taxa within the genus Quercus, it is not an easy task to figure out exactly what type of oak you may have growing in your backyard. Quercus turbinella are most often found on dry desert slopes and they flower in spring. The shrub live oak has C3 photosynthesis. One of the things to look for when identifying a sonoran scrub oak is tromentose or fuzzy twigs, but this is not always helpful as the twigs are sometimes glabrous or bald. Quercus turbinella consistently have pedunculate fruit and strongly cordate (heart-shaped) leaf bases. The leaves are usually toothed or shallowly lobed on each side and have pointy spines. In the case of the Quercus turbinella a picture is worth over a thousand words. (note: Q. turbinella is at far left.)
The Sonoran Scrub Oak has been used in the past by American Indian tribes such as the Yuma. It is reported that the acorns of Quercus turbinella were a food source. They were snacked on raw, or prepared in a variety of ways. Ground up acorn flour was used as a thickener for stew, or to make bread, and the acorns themselves were sometimes roasted and eaten like pinions. The preparation of acorns for consumption is a tedious but necessary one if you plan on eating acorns. This is because acorns contain toxic not to mention bitter tasting tannins. The Yuma left sacs of acorns for weeks at a time in rivers and streams in order to wash out most of the tannins and render the acorns palatable. The wood of the shrub live oak can be used to make handles or burned for fuel.
Click to see the distribution of Quercus turbinella in Utah
Click to see the classification and national distribution of Quercus turbinella