The Asian longhorned beetle (above) and the emerald ash borer are wreaking havoc on American forests.
The Asian longhorned beetle (above) and the emerald ash borer are wreaking havoc on American forests.

By Faith Campbell, Emeritus environmental advocate and tree-pest expert

Several of the most damaging tree-killing insects came to America as larvae riding in crates, pallets, or other forms of wood packaging material (WPM).

These include the Asian longhorned beetle (ALB), emerald ash borer, and redbay ambrosia beetle. All entered the country since trade opened with China in the late 1980s. The ALB and EAB entered before our government had adopted effective measures to prevent pests from being transported in WPM.

Responding to discovery of the ALB, U.S. and Canadian officials worked with European and other counterparts to adopt an “international standard” that requires that WPM used in international trade be treated to reduce the likelihood that live insects will be inside. Since 2006, the U.S. and Canada have required that WPM from overseas comply with this standard.

How much has relying on the international standard reduced the risk of a new pest being introduced? Analysis of USDA data suggests that applying the standard has reduced the rates at which live insects are intercepted at U.S. borders by about half. This is important progress.

Each day, 35 shipping containers bring a pest to the U.S.
Each day, 35 shipping containers bring a pest to the U.S.
Photo credit: Greg Bishop.

Still, as of 2009, one shipment out of each thousand that contain wood packaging harbors a live insect that threatens plant resources in the U.S. This sounds like a very small risk. However, an estimated 13 million shipping containers carrying wood packaging entered the U.S. in 2013. At the suggested approach rate, this means 13,000 containers harboring pests would enter the country each year – 35 per day.1 Continuing what we are doing now could result in more than 100 additional wood-boring insects being introduced over the next 40 years.2

We can do more!

U.S. and Canadian governments work with their counterparts in Asia and around the world to improve compliance with the standard’s treatment and other requirements.

Meanwhile, businesses that import goods packaged in wood can also step forward to protect the urban and wildland forests from which all Americans benefit. These businesses can help stop the spread of pests by:

  • Negotiating contracts with their foreign suppliers that hold the supplier responsible for any costs arising from failures to comply with the international standard.
  • Emphasizing to employees and contractors who manage the company’s transportation and supply chain their personal responsibility for ensuring compliance.
  • Evaluating alternatives to wood packaging – avoiding hassles at the border might make up for the higher cost of alternative types of packaging.
  • Instituting active pest surveillance at warehouses and distribution centers; reporting evidence of pests to appropriate federal and state’s authorities.

1Haack RA, Britton KO, Brockerhoff EG, Cavey JF, Garrett LJ, et al. (2014) Effectiveness of the International Phytosanitary Standard ISPM No. 15 on Reducing Wood Borer Infestation Rates in Wood Packaging Material Entering the United States. PLoS ONE 9(5): e96611. doi:10.1371/journal.pone.0096611.
2Leung, B., M.R. Springborn, J.A. Turner, E.G. Brockerhoff. 2014. Pathway-level risk analysis: the net present value of an invasive species policy in the US. The Ecological Society of America. Frontiers of Ecology.org