California scrub oak (Quercus dumosa)
California scrub oak is a type of oak tree in the Fagaceae family. This species lives in Baja, Mexico and southern California. The tree is also referred to as Nuttall’s scrub oak and the coastal sage scrub oak. Quercus dumosa is a dominant plant in the chaparral biome of the greater San Diego and Los Angeles area.
Oak trees were a primary food source for southern California Native Americans. Acorns of various oak trees were collected, leached to remove tannins, then ground into a powder meal and used to make bread or mush. However, the early settlers preferred the acorn of the live oak. In general, natives would only eat the scrub oak acorns if they couldn’t find any California live oak.
Historical uses of scrub oak
The Cahuilla, Kawaiisu and Kumeyaay people gathered acorns then stored them in primitive granaries for long term storage.
The Cahuilla people would often prepare flour meal from the scrub oak, then trade this acorn meal in exchange for preferred foods (pinyon nuts, mesquite beans and palm tree fruits).
The acorn of the scrub oak may not have tasted great, but the thick wood of the trunk and base branches did provide excellent construction material for shelters. The wood of the scrub oak also made for good firewood.
The Kumeyaay prepared a decoction of oak galls to use as an eye wash. Oak galls are large, round protrusions that grow parasitically on oak trees. These galls are caused by chemicals injected by the larvae of certain types of gall wasps.
The Luiseno people, near the Los Angeles area, also used these galls. They were applied to sores and wounds as a means to promote healing.