The olive fruit fly is the most serious pest of commercial olives in California. It is capable of rendering an entire harvest unsuitable for commercial marketing or household consumption. The larvae feed on the interior flesh of the olive allowing bacteria and fungi to thrive and cause fruit deterioration. Infested table olives can have a mushy consistency and must be rejected, while olives harvested for oil production will record higher acidity levels, significantly lowering the quality.
The olive fruit fly was first detected in Napa County during the summer of 2001 and the population has rapidly expanded. Olive fruit fly thrives in temperate agricultural orchards, ornamental landscapes, and abandoned fields. Olive fruit fly populations can be managed with various traps, sanitation, bait sprays, and barrier film sprays.