A field bioassay (2006-2007) of the flight response of the invasive redhaired pine bark beetle (RPBB), Hylurgus ligniperda (F.), was conducted in southern California. Lindgren funnel trap catches showed that (–)-á-pinene and ethanol functioned synergistically as an attractant for both sexes. Ethanol was not attractive alone, but (–)-á-pinene was moderately attractive to both sexes. Seasonal flight activity data from this study and from a wider statewide survey (2003-2006) suggested that the flight of RPBB occurred year round with major peaks in May and July, but was relatively low from August to late January. A wide range of other subcortical Coleoptera were trapped in the experiment including 22 species of Scolytidae, six species of Bostrichidae, three species of Colydiidae, and five species of Cerambycidae. Another invasive scolytid, Xyleborinus saxeseni (Ratzeburg), it responded significantly to any treatment containing ethanol and also flew year round in southern California. A native root-feeding bark beetle, Hylastes tenuis Eichhoff, responded to treatments similarly to RPBB, with a significant and synergistic response to ethanol and á-pinene. Both sexes of three native species of false powderpost beetles [Amphicerus cornutus (Pallas), Scobicia declivis (LeConte), and S. suturalis (Horn) (Coleoptera: Bostrichidae)] responded significantly to any treatment containing ethanol and flew from April to October in southern California. Both sexes of another invasive subcortical beetle, the longhorned borer, Arhopalus syriacus (Reitter) (Coleoptera: Cerambycidae) were significantly attracted to treatments with (–)-á-pinene.