The infestations of the Asian longhorned beetle (ALB) in New York and Chicago, discovered in 1996 and 1998, respectively, are believed to have originated with infested solid wood packing materials shipped to the United States from China. This insect poses a serious threat to urban trees and there is potential for vast devastation to commercial hardwood forests. Since 1998, the U.S. Department of Agriculture (USDA) has required that all wood packing materials originating in China be fumigated, heat treated, or treated with preservatives. To determine the feasibility of microwave irradiation as an alternative treatment, we performed laboratory experiments on 4- by 4- by 4-inch and 4- by 4- by 1-inch blocks of wood artificially infested with live ALB larvae and pupae with subsequent 2.45 GHz microwave energy irradiation. Temperature gradients generated both by conventional and microwave treatments were recorded. Experimental results for aspen, eastern white pine, red pine, and loblolly pine showed that temperature gradients were not consistent for short (< 3 min.) irradiation periods. However, all measurement points in the 4- by 4- by 4-inch green blocks reached 60°C within 0.5 to 5 minutes of irradiation, compared to 70 to 123 minutes with the conventional heat treatment; for the 4- by 4- by 1-inch green blocks, the times were 15 to 60 seconds with the microwave treatment versus 21 to 160 minutes with the conventional treatment. In China, both green and dry poplar blocks of the same dimensions were seeded with beetle larvae and pupae. Preliminary results showed that 30 seconds and 3 minutes of irradiation at 900 watts was lethal to larvae and pupae in green 4-by 4-by 1-inch and 4- by 4- by 4-inch poplar blocks, respectively. Only 5 seconds of irradiation was necessary to kill the larvae in dry wood. These preliminary results suggest that microwave treatment can eradicate Asian longhorned beetles in solid wood packing materials. Further trials with ALB-infested wood samples are planned to determine lethal microwave treatment protocols.
|Original language||English (US)|
|Number of pages||7|
|Journal||Forest Products Journal|
|State||Published - Jan 1 2003|
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Plant Science