A wide variety of exotic tree pests can readily be transported into the United States on untreated wooden pallets, crating, bracing, and other solid wood packing materials (SWPM). Recent introductions of forest pests associated with importation of SWPM demonstrate that current United States import regulations are inadequate to exclude such pests. Nearly all (97 percent) of the quarantine-significant tree pests found by port inspectors are associated with SWPM. In spite of current bark-free import requirements, about 9 percent of maritime shipments contain bark, which provides habitat for numerous organisms. A pest risk assessment was conducted for the SWPM pathway to document risks associated with the pathway under current import requirements. The document includes a description of SWPM pathway characteristics and assessments of potential for pest entry and establishment. The potential consequences of pest introduction, including expected environmental and economic impacts, were also assessed. The pest risk assessment team selected 19 representative species or groups of insects and fungi of potential concern for detailed assessments to represent an array of geographical origins, host types, and pest habitats. Pest risk potentials were described in relation to current regulations and practices and without regard to potential mitigation measures or proposed regulations (i.e., baseline assessment). Experts evaluated seven risk elements for each potential pest to obtain an overall qualitative ranking (high, moderate, or low pest risk potential). Four of these elements related to likelihood of introduction: (1) pest with host or commodity at origin potential, (2) entry potential, (3) establishment potential, and (4) spread potential. Elements describing consequences of introduction included (5) economic damage potential, (6) environmental damage potential, and (7) social and political considerations. To improve rating consistency, objectivity, and transparency, risk criteria were developed to define each element. In addition to the qualitative rankings, quantitative projections of economic impact were developed for seven of the potential pest species or groups based upon hypothetical scenarios of introduction and spread. Cumulative economic impacts over 30 years following pest introduction are expected to range from the tens of millions to over a billion dollars, depending upon pest species, introduction location, spread rate, and damage level. Examples of high pest risk potential for the SWPM pathway exist in both temperate and tropical and subtropical regions of origin, both conifer and hardwood host types, and for the three primary pest habitats (in deep wood, under bark, on bark) of the SWPM host material being transported. Organisms with high pest risk potentials are unlikely to be excluded solely through inspection activities and associated interdiction actions at ports of entry. Given the ubiquity of the SWPM pathway, its associated pests, and the difficulties in tracing and identifying SWPM origins and compositions, it appears that worldwide application of more stringent importation requirements may be warranted.
- solid wood packing materials,
- pest risk,
- import regulation,
- invasive species,
- exotic tree pest introduction
Available at: http://works.bepress.com/judith_pasek/23/