Thousand Oaks was first named as a subdivision of the "Old Town" area of the Conejo Valley in 1923 by developers Culver and Sturgis. Local lore says it was named in a contest by a young man named Bobby Harrington who won a bicycle and a small plot of land for submitting the winning entry.
In 1940 local Conejo School's yearbook included the "First Official Oak Census" which determined there were 3,422 oak trees in the area.
In 1964 The City of Thousand Oaks incorporated, and the name was officially adopted for the new city.
In 1970 an emergency resolution was passed to aid in protecting the oak trees of Thousand Oaks.
in 1986 the first ordinance specifying the process for the protection of oaks in Thousand Oaks was passed.
In 1989 there were an estimated 25,000 oaks in the Conejo Valley between the Conejo Grade and Agoura.
In 2023 there were estimated to be over 50,000 oaks in the Conejo Valley.
In the Conejo Valley there are three main native oak species Quercus Lobata - the Valley Oak; Quercus Agrifolia - the Coast Live Oak; Quercus dumosa - the Scrub Oak. Other California oaks include the: Black oak, Blue oak, Canyon live oak, Engelmann oak, Interior live oak, Oregon white oak, and Tanbark oak. See this link for more on native California oak trees.