Elsie Burbano, eburbano@hawaii.edu1, Mark G. Wright, markwrig@hawaii.edu1, Virginia Easton Smith, vsmith@hawaii.edu2, and Nancy Gillette, ngillette@fs.fed.us3. (1) University of Hawaii - Manoa, Department of Plant and Environmental Protection Sciences, 3050 Maile Way. Room 310, Honolulu, HI, (2) University of Hawaii, Department of Tropical Plant and Soil Sciences, UH Cooperative Extension Service, 79-7381 Mamalahoa Hwy, Kealakekua, HI, (3) U. S. Forest Service, P.O. Box 245, PSW Research Station, Berkeley, CA
Effective trapping systems and semiochemicals are described for three invasive ambrosia beetle species, Xylosandrus compactus, Xylosandrus crassiusculus, and Xyleborinus saxeseni, infesting native Hawaiian restoration stands. Xylosandrus compactus is also a serious pest of coffee worldwide. Green Japanese beetle traps baited with ethanol were the most effective traps for X. compactus and X. saxeseni, and were significantly more effective than multiple funnel traps baited with ethanol. On the other hand, Japanese beetle traps and multiple funnel traps were equally effective for trapping X. crassiusculus. Two semiochemicals, verbenone and limonene, were tested as inhibitors to the attractant ethanol. Verbenone significantly reduced trap catch of all three species. Limonene, on the other hand, reduced trap catches of all three beetles, but the difference was significant only for X. crassiusculus. Based on these results, we conclude that both semiochemicals may have promise for minimizing damage by introduced ambrosia beetles in native Hawaiian forest restoration projects. Further studies are planned to test verbenone for protection of native Hawaiian trees in nurseries, botanical gardens, and in out-plantings.
Species 1: Coleoptera Curculionidae
Xylosandrus compactus (black twig borer)