Competitive Exclusion of Dendroctonus rufipennis Induced by Pheromones of Ips tridens and Dryocoetes affaber (Coleoptera: Scolytidae)

Therese M. Poland, John H. Borden
1998 Journal of Economic Entomology  
We tested the feasibility of competitive exclusion as a potential management tactic for the spruce beetle, Dendroctonus rufipennis Kirby, using pre-attack baiting with pheromones of 2 secondary species, Ips _ Mannerheim and Dryocoetes affaber Mannerheim. Spruce beetle attack densities, gallery lengths per square meter, and progeny densities were significantly reduced ' by up to 78% in individual felled trees baited with the/. tr/dens pheromones (___)-ipsdienoland (-)-e/s-verbernol, and the D.
more » ... ernol, and the D. affaber pheromones (___)-exo-and (+)-endo-brevicomin, or phero--mones ofboth secondary species. A simplified D. affaber bait consisting of only (__+)-endo-brevicomin -also significantly reduced spruce beetle attacks, resource exploitation, and progeny production. Baiting with L tr/dens pheromones also reduced spruce beetle attack and success in simulated patches of windthrown trees. Resource exploitation and indirect interference by synomonal inhibition of spruce beetle attack are the most likely competitive mechanisms invoked. Competitive exclusion of the spruce beetle may provide an alternative management tactic where traditional methods based • on tree removal, widespread harvesting, and the use of insecticides are not feasible.
doi:10.1093/jee/91.5.1150 fatcat:2gpbsy6bczhnnaw6tvv266ms3i