Trap deployments in black walnut tree canopies help inform monitoring strategies for bark and ambrosia beetles (Coleoptera: Curculionidae: Scolytinae)

Authors: KLINGEMAN, WILLIAM - University Of Tennessee; BRAY, ALICIA - Central Connecticut State University; OLIVER, JASON - Tennessee State University; Ranger, Christopher; Palmquist, Debra

Submitted to: Environmental Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/26/2017
Publication Date: 9/11/2017
Publication URL: http://handle.nal.usda.gov/10113/5883116
Citation: Klingeman, W.E., Bray, A.M., Oliver, J.B., Ranger, C.M., Palmquist, D.E. 2017. Trap deployments in black walnut tree canopies help inform monitoring strategies for bark and ambrosia beetles (Coleoptera: Curculionidae: Scolytinae). Environmental Entomology. https://doi:10.1093/ee/nvx133.

Interpretive Summary: Thousand cankers disease is caused by plant pathogenic Geosmithia morbida Kolarík, Freeland, Utley, and Tisserat; a fungus vectored primarily by the walnut twig beetle, Pityophthorus juglandis (Blackman). The role of other bark and ambrosia beetle species in persistence and spread of this disease remains unclear. Scolytine species active within urban parks and landscapes in eastern Tennessee were monitored between 2011 and 2013 in Knox and Blount counties, which are quarantined for thousand cankers disease. Sticky panel, modified soda bottle and Lindgren traps were deployed within canopies of mature walnut trees. Panel traps were deployed at different heights, and traps were variously deployed with and without ethanol as an attractant, and with and without walnut stem sections that had been treated by girdling or by injection to simulate stressed trees tissues. A variety of bark and ambrosia beetle species were collected. Some key non-native species were more active higher in the tree than most other species and were strongly attracted to ethanol. Cnestus mutilatus, which were captured season-long and increased in abundance across the three-year study, were most abundant in late May followed by a second elevated period of activity in about late August. These results will aid in optimizing trapping tactics for exotic ambrosia beetles within the walnut canopy.

Technical Abstract: Thousand cankers disease is caused by plant pathogenic Geosmithia morbida Kolarík, Freeland, Utley, and Tisserat; a fungus vectored primarily by the walnut twig beetle, Pityophthorus juglandis (Blackman). The role of other bark and ambrosia beetle species in persistence and spread of this disease remains unclear. Scolytine species active within urban parks and landscapes in eastern Tennessee were monitored between 2011 and 2013 in Knox and Blount counties, which are quarantined for thousand cankers disease. Sticky panel, modified soda bottle and Lindgren traps were deployed within canopies of mature walnut trees. Panel traps were deployed at different heights, and traps were variously deployed with and without ethanol as an attractant, and with and without walnut stem sections, or in situ limbs, that had been treated by girdling or by injection to simulate stressed trees tissues. Bark and ambrosia beetle species that were collected in greatest abundance included Ambrosiodmus rubricollis (Eichhoff), Ambrosiophilus atratus (Eichhoff), Cnestus mutilatus (Blandford), Dryoxylon onoharaense (Murayama), Euwallacea validus (Eichhoff), Monarthrum fasciatum (Say), Monarthrum mali (Fitch), Xyleborinus saxesenii (Ratzeburg), Xyleborus affinis Eichhoff, Xyleborus ferrugineus (Fabricius), Xylosandrus crassiusculus (Motschulsky) and Xylosandrus germanus (Blandford). Cnestus mutilatus, X. saxesenii and X. crassiusculus were more active higher in the tree than most other species and were strongly attracted to ethanol via all means of lure deployment. Cnestus mutilatus, which were captured season-long and increased in abundance across the three-year study, were most abundant in late May followed by a second elevated period of activity in about late August.