Gold Spotted Oak Borer (GSOB): Monitoring and Mitigation Program

About the Program

Category: County Resiliency (Best in Category)

Year: 2020

Gold Spotted Oak Borer (GSOB) is an invasive insect initially discovered in San Diego County in 2008, then subsequently found in satellite infestations in Riverside County, Orange County, and Green Valley, Los Angeles County. This pest eventually kills its host, typically within three years of initial infestation. GSOB primarily impacts three oak species: Coast Live Oak (Quercus agrifolia), Canyon Live Oak (Quercus chrysolepis), and California Black Oak (Quercus kellogii). Control and eradication is dependent on early detection and rapid coordinated agency response (Integrated Pest Management (IPM) and infested tree removals).To minimize oak woodland loss and reduce homeowner fire risk from dead standing trees, the Los Angeles County Fire Department, Forestry Division began removing infested trees in 2015. Since then, improved processes, procedures and technology have been incorporated to mobilize resources, increasing the pace and scale of control efforts. As of January 2020, approximately 700 infested trees have been removed, with another 250 removals by March 1, 2020. Reforestation by growing and planting a minimum of 1,500 replacement oaks is included in the program. Additionally, a pilot using systemic pesticides will be trialed in 2020, to save the resource rather than removing trees: the ultimate goal of the mitigation program.