Brood production by three species of Dendroctonus (Coleoptera: Scolytidae) in bolts from host & non-host trees

Brood establishment and production by mountain pine beetles, Douglas-fir beetles and spruce beetles were investigated in the laboratory, in 40 cm bolts of subalpine fir, spruce (<i>Picea glauca</i> x <i>P. engelmannii</i> hybrid), lodgepole pine and Douglas-fir. In subalpine fir, a few eggs were laid by mountain pine and spruce and Douglas-fir beetles but no brood matured. Production of egg galleries by spruce beetles in this host was the same as it was in spruce, its principal host. In Douglas-fir, eggs were produced only by Douglas-fir beetles and the production of galleries by this bark beetle was significantly greater than that by either of the other beetles. All three beetle species produced mature broods in lodgepole pine and in spruce