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

As I said in my previous blog, many damaging pests enter the United States by hiding inside wood packaging material (WPM) such as crates and pallets.

What types of imports pose the greatest risk of carrying unwanted insect pests in crates and pallets? Heavy items, such as machinery (including electronics); metals; and tiles and decorative stone (such as marble or granite counter tops). Indeed, more pests have been found in wood supporting tiles and stone than any other type of commodity in 24 of the past 25 years.1

Which parts of the country import the highest volumes of these goods?2 It is probably not surprising that the Port of New York leads all other U.S. cities in imports of both machinery and decorative tiles and stone from Asia, Europe and Central America. Other ports ranking near the top in these shipments include:

  • Baltimore
  • Seattle
  • Los Angeles/Long Beach
  • Chicago
  • San Francisco
  • Jacksonville
  • Atlanta
  • Philadelphia
  • Washington, D.C.
  • Boston
  • Portland
  • Houston

The U.S. Bureau of Customs and Border Protection inspects incoming shipments. In recent years, they have found pests in the WPM contained in about 1,000 containers, but we know that some infested shipments escape detection. As I suggested in my previous blog, U.S. importers of machinery, metals and decorative tile and stone should increase their efforts to clean up their supply chains and be vigilant of possible pests in their warehouses.

Stay tuned for more about the invasive pests threatening America’s urban and wildland forests!

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
2Data for this blog was taken from Colunga-Garcia, M., M., R.A. Haack, and A.O. Adelaja. 2009. Freight Transportation and the Potential for Invasions of Exotic Insects in Urban and Periurban Forests of the US. J. Econ. Entomol. 102(1): 237-246 (2009) ; or from raw data provided by the lead author.