ALEXANDER VERTIKOFF Among the masterworks by architects and brothers Charles and Henry Greene is the Gamble House (above), built in the early 20th century in Pasadena.

Two of the most celebrated designers of the American Arts and Crafts movement lived and worked for most of their careers in Southern California. On Saturday, The Huntington Library, Art Collections, and Botanical Gardens, in partnership with the Gamble House, USC, of Pasadena, will present the most comprehensive exhibition undertaken on the work of architects Henry Mather Greene and Charles Sumner Greene.

After touring The Huntington's Greene & Greene show, make time to visit another new exhibit that explores the influence of plants on Charles Darwin's theory of evolution. “Darwin's Garden: An Evolutionary Adventure” is on display in the West Hall of the Huntington Library through Jan. 5.

One tree = big difference. If every American family planted just one tree, the amount of carbon dioxide (CO2) in the atmosphere would be reduced by 1 billion pounds annually.