Video: GSOB Overview
History and Background
GSOB has been documented since the late 1800?s. This is apparent from museum records from southeastern Arizona, southern Mexico, and northern Guatemala (MAP). Collection dates for adult museum specimen ranged from May through September. GSOB was first collected in California in 2004. In southern California, GSOB currently occurs in a roughly 31 x 25 mile area of east San Diego County.
Oak damage associated with GSOB was first confirmed in the County of San Diego in 2008, however elevated levels of oak mortality have been mapped aerially on and around the Cleveland National Forest since 2002.
At present there are no reports linking GSOB to damage in oaks outside of California. Although some have attributed its presence in southern California to range expansion from its native populations to the east and south, but reports suggest that GSOB may have been introduced during the last ten years on oak firewood brought in from Mexico.