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Wood makes great packaging material—it’s inexpensive, abundant and versatile—but there’s one drawback: destructive forest pests stowaway in the pallets, crates and dunnage (wood used to brace cargo) used in international shipping. Over many years, international trade has resulted in the inadvertent introduction of many non-native wood-feeding pests and plant pathogens in the U.S. and throughout the world. Some of these non-native insects, including the emerald ash borer and the Asian longhorned beetle, have become highly invasive and caused serious environmental and economic impacts.
But an international standard for wood packaging material is slowing the inadvertent export of invasive bark- and wood-boring insects, according to a study conducted by Robert Haack, a research entomologist with the Forest Service’s Northern Research Station in Lansing, Mich., and a team of scientists. Researchers found as much as a 52 percent drop in infestation rates in the U.S., where the standard was implemented in three phases between 2005 and 2006. The study was published May 14 in the journal PLOS ONE.
The International Standards for Phytosanitary Measures No. 15, or ISPM 15, is a set of standards developed by the International Plant Protection Convention stipulating how wood packaging material used in international trade should be treated before export. Treatments for eliminating live insects that may be contained in wood include heating wood, fumigating it and requiring the removal of bark from wood used for wood packaging material. As of October 2013, more than 78 countries had implemented ISPM 15.
Haack and co-authors of the study, including U.S. Department of Agriculture scientists Kerry Britton (now retired), Joseph F. Cavey and Lynn J. Garrett, believe that the drop in infestation rates would be even more dramatic if more data had been collected prior to implementation of the standard. The best available data in the U.S. only allowed researchers to compare wood packaging infestation rates from two years prior to U.S. implementation of the new international standard to infestation rates during the first four years after the standards were implemented.
“The reduction in infestation rate would likely have been even higher if we had more years of data that predated U.S. implementation of these international standards,” Haack said. “For example, based on infestation data of wood packaging material entering New Zealand from the early 1990s, when infestation rates were higher, ISPM 15 has achieved closer to a 97 percent reduction in the number of insect stowaways.”