Published online by Cambridge University Press: 31 May 2012
Lodgepole pines, Pinus contorta var. contorta Engelmann, killed by mountain pine beetle, Dendroctonus ponderosae Hopkins, are often subsequently infested by other scolytid species (Safranyik et al. 1996). Ips pini (Say) breeds in the phloem region of the main bole and larger branches in areas not occupied by mountain pine beetle. Adults emerge in the fall and drop to overwinter in the duff near the bases of their brood trees (Safranyik et al. 1996). Hylurgops porosus (LeConte) infests lodgepole pine (Keen 1952; Bright 1976) stumps or severely weakened trees near the root collar and in large roots (Wood 1982). We examined the pattern of emergence of I. pini and H. porosus from the duff around infested trees to describe changes in density over distance from the trees.