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. 2014 May 14;9(5):e96611. doi: 10.1371/journal.pone.0096611. eCollection 2014.


Numerous bark- and wood-infesting insects have been introduced to new countries by international trade where some have caused severe environmental and economic damage. Wood packaging material (WPM), such as pallets, is one of the high risk pathways for the introduction of wood pests. International recognition of this risk resulted in adoption of International Standards for Phytosanitary Measures No. 15 (ISPM15) in 2002, which provides treatment standards for WPM used in international trade. ISPM15 was originally developed by members of the International Plant Protection Convention to "practically eliminate" the risk of international transport of most bark and wood pests via WPM. The United States (US) implemented ISPM15 in three phases during 2005-2006. We compared pest interception rates of WPM inspected at US ports before and after US implementation of ISPM15 using the US Department of Agriculture AQIM (Agriculture Quarantine Inspection Monitoring) database. Analyses of records from 2003-2009 indicated that WPM infestation rates declined 36-52% following ISPM15 implementation, with results varying in statistical significance depending on the selected starting parameters. Power analyses of the AQIM data indicated there was at least a 95% chance of detecting a statistically significant reduction in infestation rates if they dropped by 90% post-ISPM15, but the probability fell as the impact of ISPM15 lessened. We discuss several factors that could have reduced the apparent impact of ISPM15 on lowering WPM infestation levels, and suggest ways that ISPM15 could be improved. The paucity of international interception data impeded our ability to conduct more thorough analyses of the impact of ISPM15, and demonstrates the need for well-planned sampling programs before and after implementation of major phytosanitary policies so that their effectiveness can be assessed. We also present summary data for bark- and wood-boring insects intercepted on WPM at US ports during 1984-2008.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Disinfectants / pharmacology
  • Ectoparasitic Infestations / prevention & control*
  • Guidelines as Topic
  • Insect Control / legislation & jurisprudence
  • Insect Control / statistics & numerical data*
  • Insecta / drug effects
  • Insecta / physiology
  • Product Packaging
  • Quarantine / legislation & jurisprudence*
  • United States
  • United States Department of Agriculture
  • Wood / parasitology*


  • Disinfectants

Grant support

The Working Group “Effects of trade policy on management of non-native forest pests and pathogens” was supported by a grant from The Nature Conservancy to the National Center for Ecological Analysis and Synthesis, which is a Center funded by the National Science Foundation (Grant #EF-0553768), the University of California Santa Barbara, and the State of California. Partial funding was provided by the New Zealand Foundation for Research and Technology through contracts C02X0501 (Better Border Biosecurity) and C04X0302 (Forest Biosecurity and Protection) to the author EGB. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.