Calaveras Big Trees Association (CBTA)  can trace its roots to the original Calaveras Grove Association organized in 1926 by a group of individuals intent on preserving the historic groves for future generations. Through their efforts Calaveras Big Trees State Park was born on July 5, 1931.

The Calaveras Big Trees Association was founded in 1974 by a new group of interested people with a revised purpose:  as a private, non-profit, charitable 501(c)(3) corporation to support the interpretive and environmental educational programs at Calaveras Big Trees State Park. These programs enable visitors to understand, appreciate, conserve, enjoy and explore Calaveras Big Trees State Park.  CBTA uses membership fees, donations and fundraising to accomplish this mission. Membership is open to individuals, families, and businesses.  The board members are all volunteers.