Searching for California's Hang Trees (2000 – ongoing) grew out of Gonzales-Day's research into the history of lynching in California and continues to build the most comprehensive record of lynching in California. Searching for California's Hang Trees serves as a physical testimony to Gonzales-Day’s research visits to over 300 alleged lynching sites in California. The images also show the intrusion of time and development, or 'progress', around the trees and upon the landscape: roads, buildings, construction sites – all signifying to a certain extent the idea of the past being buried or covered up – another form of "erasure".
Exclusively employing an antique Deardorff large format camera, the artist engages with the history of landscape photography in California and recalls the legacies of violence associated with US colonialism and Manifest Destiny. Gonzales-Day spent several years researching in local archives and scanning microfilm while making multiple expeditions across the state looking for clues to the little-known history. Though ambitious in scope, the artist places great importance in searching for and finding as many of these sites as possible in order to bear belated historical witness to these locations and contemplate what they represent. The research and records for over 353 cases documented by Gonzales-Day is in no way complete, but has become the most complete list of cases published to date.