Abstract
Heydenia unica Cook & Davis, a larval parasite of the southern pine beetle, Dendroctonus frontalis Zimmerman, was attracted in significant numbers to olfactometers baited with the beetle pheromones and a host- tree terpene. The host-tree terpene, a-pinene, attracted considerably more H. unica than did the individual pheromones, which did not attract significantly more than the control.