USDA APHIS has formally proposed to end its regulatory program aimed at slowing the spread of the emerald ash borer (EAB) within the United States. APHIS proposes to rely on biological control to reduce impacts and – possibly – slow EAB’s spread. The proposal and accompanying “regulatory flexibility analysis” are posted here.
Public comments on this proposed change are due 19 November, 2018.
I will blog more fully about this issue in coming weeks. At present, I am on the fence regarding this change.
On the one hand, I recognize that APHIS has spent considerable effort and resources over 16 years trying to prevent spread of EAB – with less success than most would consider satisfactory. (EAB is known to be in 31 states and the District of Columbia now). While APHIS received tens of millions of dollars in emergency funding in the beginning, in recent years funding has shrunk. Over the past couple of years, APHIS has spent $6 – $7 million on EAB out of a total of about $54 million for addressing “tree and wood pests.” (See my blogs on appropriations by visiting www.cisp.us, scrolling down to “topics,” then scrolling down to “funding”). Funding has not risen to reflect the rising number of introduced pests. Presumably partly in response, APHIS has avoided initiating programs targetting additional tree-killing pests. For example, see my blogs on the shot hole borers in southern California and the velvet longhorned beetle by visiting www.cisp.us, scrolling down to “categories,” then scrolling down to “forest pest insects”. I see a strong need for new programs on new pests and money now allocated to EAB might help fund such programs.
On the other hand, APHIS says EAB currently occupies a quarter of the range of ash trees in the U.S. Abandoning slow-the-spread efforts put at risk trees occupying three quarters of the range of the genus in the country. (See APHIS’ map of infested areas here.) Additional ashes in Canada and Mexico are also at risk. Mexico is home to 13 species of ash – and the most likely pathway by which they will be put at risk to EAB is by spread from the U.S. However, APHIS makes no mention of these species’ presence nor USDA’s role in determining their fate.
I am concerned by the absence of information on several key aspects of the proposal.
APHIS makes no attempt to analyze the costs to states, municipalities, homeowners, etc. if EAB spreads to parts of the country where it is not yet established – primarily the West coast. As a result, the “economic analysis” covers only the reduced costs to entities within the quarantined areas which would be freed from requirements of compliance agreements to which they are subject under the current regulations. APHIS estimates that the more than 800 sawmills, logging/lumber producers, firewood producers, and pallet manufacturers now operating under compliance agreements would save between $9.8 M and $27.8 million annually. This appears to be a significant benefit – but it loses any meaning absent any estimate of the costs that will be absorbed by governments and private entities now outside the EAB-infested area.
ash tree killed by EAB; Ann Arbor, MI; courtesy of former mayor of Ann Arbor, MI John Hieftje
APHIS does not discuss how it would reallocate the $6 – 7 million it spends on EAB. Would it all go to EAB biocontrol? Would some be allocated to other tree-killing pests that APHIS currently ignores?
APHIS provides no analysis of the efficacy of biocontrol in controlling EAB. It does not even summarize studies that have addressed past and current releases of EAB-specific biocontrol agents. (I will report on my reading of biocontrol studies in a future blog.)
APHIS says efforts are under way to develop programs to reduce the risk of pest spread via firewood movement. APHIS does not explain what those efforts are or why they are likely to be more effective than efforts undertaken in response to recommendations from the Firewood Task Force issued in 2010.
APHIS makes no attempt to analyze environmental impacts.
champion green ash in Michigan killed by EAB
APHIS says nothing about possibly supporting efforts to breed ash trees resistant to EAB.
I welcome your input on these issues.
I will inform you of my evolving thinking, information obtained in efforts to fill in these gaps, etc. in future blogs.
Posted by Faith Campbell
We welcome comments that supplement or correct factual information, suggest new approaches, or promote thoughtful consideration. We post comments that disagree with us — but not those we judge to be not civil or inflammatory.
There is widespread agreement that the most important pathways for long-distance transport of non-native forest insects are wood packaging (crates, pallets, dunnage, etc.) and imports of live plants (which APHIS calls “plants for planting”). Sources (at end of blog): Aukema et al. 2010; Liebhold et al. 2012; Meurisse et al. 2018 and many others. See also my earlier blogs by scrolling down to the “categories” section and clicking on “wood packaging”.
According to Meurisse et al., by the middle of this decade, world maritime freight trade had reached about 10 billion metric tonnes, and air transport of cargo had reached 50 million tonnes – much of it packaged in wood.
As the world’s biggest importer, the United States receives about 27 million shipping containers each year (CBP to FT Campbell). A study carried out in 2005 – 2007 (Meissner et al. 2009) indicated that 75% of maritime shipments entering the U.S. contained wood packaging; 33% of air shipments contained wood packaging. These are significant increases over earlier estimates that put the number of containers entering the country at 25 million. An even older analysis estimated that 52% of incoming containers had wood packaging.
APHIS has recognized the pest risk associated with wood packaging for 20 years – since the Asian longhorned beetle was detected in a second city – Chicago – in 1998. APHIS and its Canadian counterpart (Canadian Food Inspection Agency) acted rapidly to adopt, first, domestic regulations governing wood packaging from China (in December 1998), then a regional standard for wood packaging, and finally to help bring about adoption of International Standard for Phytosanitary Measures (ISPM) No. 15 in 2002. A detailed description of these actions can be found in my report Fading Forests II available here.
However, as I have demonstrated often, ISPM#15 has reduced the threat – but insufficiently. Dr. Robert Haack and his coauthors (2014) found that of each thousand shipments containing wood packaging that enters the country, one harbors a quarantine pest. Applying this estimate to the current volume of incoming containers and the higher proportion containing wood packaging results in an estimate that up to 20,000 shipping containers containing infested wood packaging enter the country each year – or approximately 55 per day.
The actual approach rate might be less. There are two variables that I lack sufficient data to quantify.
First, a significant proportion of the incoming containers come from Mexico or Canada – our second and third largest trading partners. The risk of damaging pests arriving from our neighbors is less than the risk accompanying shipments from overseas – although it is not “0”. Several woodborers native to Mexico have been introduced to U.S. ecosystems and are killing trees in these new environments, e.g., goldspotted oak borer, walnut twig beetle, and soapberry borer (all described in write-ups here). It is true that these beetles were probably introduced to vulnerable parts of the U.S. in firewood rather than wood packaging. There are also reasons to be concerned about pest introductions from Canada. Threats arise from both non-native pests established in the country e.g., brown spruce longhorned beetle and European beech leaf weevil, and pests in shipments from off-shore origins that are re-packaged in Canada (Yemshanov et al. 2012 and my earlier blog from April 2017).
The second variable on which I lack data is the proportion of the 27 million containers that are transported by air, and are thus half as likely to contain wood packaging.
To account for these unknowns, I have nearly halved the number of shipping containers likely to transport pests from off-shore – so 14 million instead of 27 million. Again applying Haack’s estimate, the result is 10,500 shipping containers containing infested wood packaging entering the country every year – or approximately 29 every day.
Update with more precise data (August 24) :
Re: the two variables, I have found partial answers from a U.S. Department of Transportation website which provides data on imports of loaded chipping containers (in TEUs) for 68 ports. (For the website, go here – click on “trade statistics”, then “US Waterborne trade” (1st bullet)]
As of 2017, 22,360,941 loaded shipping containers entered the U.S. via maritime transport. Applying the estimate of 75% of these containers holding wood packaging, we find that slightly less than 17 million containers entered the country with wood packaging. Applying Robert Haack’s estimate that one in a thousand is infested with a quarantine insect, we anticipate that 17,000 of these containers were transporting a pest that threatens our country. That is 46 containers every day.
Ports which received the largest numbers of containers, according to the DoT database:
Long Beach/Los Angeles — 8.4 million containers
New York — 3.4 million containers
Savannah — 1.8
Norfolk — 1.2
Houston — 1 million containers
We need answers!
The point is, we don’t know how many pests are reaching the United States daily. Or if the current approach rate is significantly higher or lower than in the past. Despite my urging, APHIS has not undertaken a study to update Haack’s estimate – which is based on 2009 data. In the intervening nine years, several changes were made to ISPM#15 to make it more effective. The most important was restricting the size of bark remnants that may remain on the wood.
Also, we might hope that experience with implementing the standard has led to better compliance. Unfortunately, available data do not encourage belief that compliance has improved.
Customs and Border Protection (CBP) reports annually to the Continental Dialogue on Non-Native Forest Insects and Diseases on the number of import shipments with wood packaging that have been detected as not complying with ISPM#15. Over a period of eight years – Fiscal years 2010 through 2017 – CBP detected nearly 24,000 non-compliant shipments. While most (17,413) of the non-compliances were crates or pallets that lacked the required mark showing treatment in accordance with ISPM#15, in 6,388 cases the wood packaging actually harbored a pest in a regulated taxonomic group. This works out to about 800 infested shipments detected each year.
By comparing Dr. Haack’s estimate with the CBP data, I estimate that Customs is detecting and halting the importation of four to eight percent of the shipments that actually contain pest-infested wood. Since CBP inspects only about two percent of incoming shipments, this detection rate demonstrates the value of CBP’s program to target likely violators – and deserves praise. But it is obviously too low a “catch” rate to provide an adequate level of protection for our forests.
Indeed, using the older, lower estimates of both numbers of shipping containers and the proportion that contain wood packaging, Leung et al. 2014 concluded that continuing to implement ISPM#15 at the efficacy level described by Haack et al. would result in a tripling of the number of non-native wood-boring insects introduced into the U.S. by 2050.
CBP inspector views Cerambycid larvae found in wood packaging that bears ISPM#15 stamp
Closer examination of the data raises more troubling questions. On average, 97% of the 6,388 shipments containing infested wood pieces detected by CBP were found in wood that bore the ISPM#15 stamp indicating that it had been treated. The proportion of infested shipments bearing the stamp has not changed over the past eight years. This is alarming and we need to understand the reason. Does this finding indicate widespread fraud? I understand that most inspectors believe this is the cause. Other possible explanations are accidental misapplication of the treatments or the treatments simply not working as expected. APHIS researchers have found that larvae from wood subjected to methyl bromide fumigation were more likely to survive to adulthood than those intercepted in wood that had been heat treated (Nadel et al. 2016). Does this indicate that methyl bromide fumigation is less effective? What effort is APHIS making to determine which of these explanations is correct?
Certain countries have a long-standing record of non-compliance with ISPM#15. APHIS’ database of pest interceptions on wood packaging over the period Fiscal Year 2011 to FY 2016 contains 2,547 records of insect detections from dozens of countries. The countries of origin with the highest numbers of shipments detected to have pests present were Mexico, China, Italy, and Costa Rica. These numbers reflect in part the huge volumes of goods imported from both Mexico and China. But China and Italy stand out for their poor performance. (The U.S. does not regulate – or inspect! – wood packaging from Canada; see blog here.)
Meissner et al. say that as of a decade ago, Chinese shipments were only half as likely to be enclosed in wood packaging as are shipments from other exporters. Yet shipments from China still rank second in the number of non-compliant shipments; they make up 11% of all interceptions. In part, the data reflect inspection priorities: due to the great damage caused by Asian insects to North American trees and the past record of poor compliance, CBP targets shipments from China for more intense scrutiny. Still, the high number of detections reflects continuing non-compliance by Chinese exporters. And remember – the U.S. and Canada began requiring treatment of wood packaging from China at the end of 1998 – nearly 20 years ago! [Feb 17 blog]
We don’t import a lot of goods from Italy – but Italian shipments of decorative stone and tile have always been plagued by high levels of pests in accompanying wood packaging. Indeed, more pests have been found in wood supporting tiles and stone than any other type of commodity in 24 of the 25 years preceding 2014 (Haack et al. 2014).
What is APHIS doing to pressure these countries to improve their compliance? As I blogged in October, link the Bureau of Customs and Border Protection began imposing a financial penalty on first-time violators in November 2017. Since interception data do not provide an adequate measure of the pest approach rate (see Haack et al 2014 for an explanation), APHIS should commission an analysis of Agriculture Quarantine Inspection Monitoring data to determine the pest approach rate before and after the CBP action in order to determine whether the more aggressive enforcement has led to reductions in non-compliant shipments at the border.
What Can Be Done to Slow or Eliminate this Pathway?
I reiterate my call for holding foreign suppliers responsible for complying with ISPM#15. One approach is to penalize violators. Now that the Bureau of Customs and Border Protection has toughened its enforcement, the U.S. Department of Agriculture should drop its decade-old policy of allowing importers to accumulate five (detected) violations in a calendar year before applying the civil penalties authorized by the Plant Protection Act.
Another step APHIS should take would be to prohibit use of packaging made from solid wood (boards, 4 x 4s, etc.) by foreign suppliers which have a record of repeated violations over the 12 years that ISPM#15 has been in effect – or the 19 + years for exporters from Hong Kong & mainland China. Officials should allow continued imports from those same suppliers as long as they are contained in other types of packaging materials, including plastic, metals, fiberboards …
SOURCES
Aukema, J.E., D.G. McCullough, B. Von Holle, A.M. Liebhold, K. Britton, & S.J. Frankel. 2010. Historical Accumulation of Nonindigenous Forest Pests in the Continental United States. Bioscience. December 2010 / Vol. 60 No. 11
Haack, R. A., K. O. Britton, E. G. Brockerhoff, J. F. Cavey, L. J. Garrett, M. Kimberley, F. Lowenstein, A. Nuding, L. J. Olson, J. Turner, and K. N. Vasilaky. 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:e96611.
Hulme, P.E. 2009. Trade, transport and trouble: Managing invasive species pathways in an era of globalization. Journal of Applied Ecology 46:10-18
Jung, T. et al. 2015 “Widespread Phytophthora infestations in European nurseries put forest, semi-natural and horticultural ecosystems at high risk of Phytophthora disease” Forest Pathology. November 2015; available from Resource Gate
Klapwijk, M.J., A.J. M. Hopkins, L. Eriksson, M. Pettersson, M. Schroeder, A. Lindelo¨w, J. Ro¨nnberg, E.C.H. Keskitalo, M. Kenis. 2016. Reducing the risk of invasive forest pests and pathogens: Combining legislation, targeted management and public awareness. Ambio 2016, 45(Suppl. 2):S223–S234 DOI 10.1007/s13280-015-0748-3
Koch, F.H., D. Yemshanov, M. Colunga-Garcia, R.D. Magarey, W.D. Smith. 2011. Potential establishment of alien-invasive forest insect species in the United States: where and how many? Biol Invasions (2011) 13:969–985
Leung, 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
Levinson, M. The Box: How the Shipping Container Made the World Smaller and the World Economy Bigger Princeton University Press 2008
Liebhold, A.M., E.G. Brockerhoff, L.J. Garrett, J.L. Parke, and K.O. Britton. 2012. Live Plant Imports: the Major Pathway for Forest Insect and Pathogen Invasions of the US. www.frontiersinecology.org
Meissner, H., A. Lemay, C. Bertone, K. Schwartzburg, L. Ferguson, L. Newton. 2009. Evaluation of Pathways for Exotic Plant Pest Movement into and within the Greater Caribbean Region. Caribbean Invasive Species Working Group (CISWG) and USDA APHIS Plant Epidemiology and Risk Analysis Laboratory
Meurisse, N. D. Rassaati, B.P. Hurley, E.G. Brockerhoff, R.A. Haack. 2018. Common Pathways by which NIS forest insects move internationally and domestically. Journal of Pest Science. https://doi.org/10.1007/s10340-018-0990-0
Nadel, H., S. Myers, J. Molongoski, Y. Wu, S. Linafelter, A. Ray, S. Krishnankutty, A. 2016. Identificantion of Port Interceptions in Wood Packaging Material Cumulative Progress Report, April 2012 – August 2016
Yemshanov, D., F.H. Koch, M. Ducey, K. Koehler. 2012. Trade-associated pathways of alien forest insect entries in Canada. Biol Invasions (2012) 14:797–812
Posted by Faith Campbell
We welcome comments that supplement or correct factual information, suggest new approaches, or promote thoughtful consideration. We post comments that disagree with us — but not those we judge to be not civil or inflammatory.
The number of new pathogens discovered each year on 131 focal host plant species in New Zealand (closed circles) and the mean annual rate of pathogen arrival estimated from the model (solid blue line), with shading showing the 95% credible interval.
Benjamin A. Sikes and several coauthors (article available here; open access!) find that targetted biosecurity programs can reduce the establishment of nonnative pathogens even while global trade and travel continue to increase.
The study relies on data from New Zealand because that country has more than 150 years of data on phytosanitary policies and pathogen introductions. Do other countries have data that would support a comparative study in order to test the authors’ conclusions more generally?
The study is unusual in analyzing introductions of a variety of forms of pathogens (fungi, oomycetes, and plasmodiophorids) rather than invertebrates. Pathogens pose significant plant health risks but are notoriously difficult to detect. The study used data on plant-pathogen associations recorded in New Zealand between 1847 and 2012. It focused on hosts in four primary production sectors: crops (46 species, including wheat, tomatoes, and onions); fruit trees (30 species, including grapes, apples, and kiwifruit); commercial forestry (42 species, including pines and eucalypts); and pastures (13 species of forage grasses and legumes). In total, 466 pathogen species for which the first New Zealand record was on one of these 131 host plants were included in the study. The pathogens were assumed to have arrived on imports seeds or fresh fruits of plants in the same family as the 131 hosts in the various production sectors.
After calculating each pathogen’s probable date of introduction, the authors compared those dates to contemporaneous levels of imports and incoming international travellers. Sikes et al. applied statistical techniques to adjust their data to the fact that detection of pathogens is particularly sensitive to variation in survey effort.
Findings:
The annual arrival rate of new fungal pathogens increased exponentially from 1880 to ~1980 in parallel with increasing import trade volumes. Subsequently rates stabilized despite continued rapid growth in not only imports but also in arrivals of international passengers.
However, there were significant differences among the four primary production sectors.
Arrival rates for pathogens associated with crops declined beginning in the 1970s but slightly earlier for those associated with pasture species. These declines occurred despite increasing import volumes.
Arrival rates of pathogens that attack forestry tree species continued to increase after 1960.
Arrival rates for pathogens that attack fruit tree species remained steady while import volumes rose steadily
Sikes et al. attribute these contrasting trends between production sectors to differences in New Zealand’s biosecurity efforts. They record when phytosanitary restrictions targetting the four sectors were adopted and link those changes to reductions in numbers of pathogens detected a decade or so later. They conclude that targetted biosecurity can slow pathogen arrival and establishment despite increasing trade and international movement of people.
Regarding the contrasting situation of the forestry and fruit tree sectors, Sikes et al. note that while phytosanitary inspections of timber imports was initiated in 1949, it focussed primarily on invertebrate pests. In addition, surveys for pathogens on fruit tree and forestry species were less robust than in the cases of crop and pasture species, and the peak survey effort occurred several decades later – in 1980 for fruit trees, 2000 for forestry species.
Furthermore, pathogens of forestry and fruit tree species can be introduced on types of imports other than seeds and fresh fruits, including soil and live plant material (e.g., rootstock) and untreated wood products.
Sikes et al. say there is no evidence of slowed pathogen arrival rates resulting from imposition of post-entry quarantine to live plant material beginning in the 1990s. I find this very troubling. Post-entry quarantine is a high-cost strategy. Still, several plant pathologists have advocated adoption of this strategy because they believed it would be sufficiently more effective in preventing introductions of – especially! – pathogens as to be worthwhile. Do others have data with which to add to our understanding of this disturbing phenomenon?
The authors suggest that introductions of tree-attacking pathogens on rising imports of wood packaging might have swamped decreases in introductions via other vectors. They consider that implementation of International Standard for Phytosanitary Measures (ISPM) No. 15 in 2002 means it is too early to see its impact in detection data. As I have blogged several times, implementation of ISPM#15 by the United States, at least, has reduced presence of detected pests – primarily insects – by 52%. Little is known about the presence of pathogens on wood packaging – according to some experts, inspectors rarely even look for pathogens. So I think the authors’ suggestion might not fully explain the continuing introduction of pathogens that attack tree species used in plantation forestry in New Zealand.
Prof. Michael Wingfield of South Africa has written numerous articles on the spread of pathogens that attack Eucalyptus on seeds imported to establish plantations in various countries; one such article is available here. This seems a more likely explanation to me.
The study’s analysis demonstrated that the overall rate of non-native fungal pathogen establishment in New Zealand was more strongly linked to changes in import trade volume than to changes in numbers of international passengers arriving on the islands. Although Sikes et al. don’t explicitly raise the question, they note that New Zealand has put considerable effort into screening incoming people – which appears from these data to have a smaller payoff than imposing phytosanitary controls on imports.
Recent declines in surveys mean the authors must estimate current pathogen arrival rates. The data gaps exacerbate the inevitable uncertainty associated with the time lag between when an introduction occurs and when it is detected. They estimate that an average of 5.9 new species of fungal pathogens per year have established on the focal host plant species since 2000. They estimate further that 55 species of pathogens are present in New Zealand but have not yet been detected there.
I am quite troubled by the reported decline in New Zealand’s postborder pathogen survey efforts since about 2000. This appears very unwise given that the risk of new introductions of pathogens that attack fruit and forestry trees continues – or even rises! Indeed, scientists associated with the forestry industry note the risk to Douglas-fir and Monterrey (Radiata) pine plantations from the pitch canker fungus Fusarium circinatum – which could be introduced on imported seeds, nursery stock, and even wood chips. Radiata pine makes up 92% of softwoods planted – and exotic softwoods constitute 97% of the plantation forestry industry.
Furthermore, non-native pathogens threaten New Zealand’s unique forest ecosystems. Since this study focused on non-native plant hosts, it does not address the risk to native forest species. However, the threat is real: Kauri trees – the dominant canopy species in some native forest types – is suffering from a dieback caused by an introduced Phythopthora. Also, two other pathogens threaten the many trees and shrubs in the Myrtaceae family found in New Zealand – Puccinia rust (which is established in Australia but not New Zealand) or the Ceratocystis fungi causing rapid ohia death – both threaten native forests in Hawai`i, as discussed in a recent blog.
Posted by Faith Campbell
We welcome comments that supplement or correct factual information, suggest new approaches, or promote thoughtful consideration. We post comments that disagree with us — but not those we judge to be not civil or inflammatory.
As I wrote in my blog in October, the Department of Homeland Security Bureau of Customs and Border Protection (CBP) has reversed a previous policy and now has the option to impose a financial penalty on importers when any of their shipments does not comply with the international standard for wood packaging (International Standard for Phytosanitary Measure Number 15 – or ISPM#15). The penalties are assessed under Custom’s authority per Title 19 United States Code (USC) § 1595a(b) or 19 USC § 1592.
The Department of Agriculture has its own legal authority to penalize shippers whose wood packaging violates regulations implementing ISPM#15. However, USDA not taken the equivalent step of using its own authority to crack down on violators. Why not?
APHIS’ legal authority stems from the Plant Protection Act of 2000 [7 U.S.C. §7701, et seq. (2000)] (The text is posted here)
This law provides broad authority to APHIS to penalize non-compliant importers, using both civil and criminal penalties. Under Section 7734 (b):
“Any person that violates this chapter … may, after notice and opportunity for a hearing on the record, be assessed a civil penalty by the Secretary…” The penalty can vary from $50,000 to $1 million, depending on whether the importer is an individual or a corporation; the number of violations adjudicated in the proceeding; the gravity of the violation; and the importer’s ability to pay. Civil penalties can be assessed regardless of whether the violation was intentional (in the language of the statute, “willful”).
Under Section 7734(a), the Department may seek criminal penalties in cases when the importer “knowingly” violated the law and its implementing regulations. Criminal penalties include both fines and imprisonment. To apply a criminal penalty, USDA must convict the importer in a trial – prove the violation beyond a reasonable doubt.
It is puzzling that USDA has not acted on this authority.
As we all know, the biological diversity of America’s forests’ is severely threatened by wood-borers that can enter the country in wood packaging. Tree mortality caused by non-native pests has been estimated to cost municipalities $1.7 billion per year (Aukema et al. 2011). For discussions of introduced pests’ impacts, see the sources listed at the end of this blog.
Nearly 12 years after APHIS adopted regulations implementing the formal International Standard for wood packaging, significant numbers of shipments that do not comply with the regulations continue to arrive. In the fiscal year that ended on September 30, Customs detected 2,000 shipments in which the wood packaging did not bear the mark certifying that the wood had been treated in accordance with ISPM#15. In nearly 900 additional shipments, CBP detected damaging pests in the wood packaging. (For more detail on this issue, see my blog from last February.) link. So, the need to improve compliance is manifest. Imposing a financial penalty strikes me as an available and useful strategy to achieve that improvement.
The new CBP policy is a much-needed step. Now USDA should reinforce that action by implementing its own enforcement powers. The USDA’s Office of General Counsel and APHIS should be asked what is preventing implementation and what can be done to move this forward. Effective action to interdict forest pests requires strong enforcement by both CBP and USDA. Right now, it looks like the Department of Homeland Security cares about U.S. forests more than the Department of Agriculture.
SOURCES
Aukema, J.E., B. Leung, K. Kovacs, C. Chivers, K. O. Britton, J. Englin, S.J. Frankel, R. G. Haight, T. P. Holmes, A. Liebhold, D.G. McCullough, B. Von Holle.. 2011. Economic Impacts of Non-Native Forest Insects in the Continental United States PLoS One September 2011 (Volume 6 Issue 9)
Lovett, G.M., M. Weiss, A.M. Liebhold, T.P. Holmes, B. Leung, K.F. Lambert, D.A. Orwig , F.T. Campbell, J. Rosenthal, D.G. McCullough, R. Wildova, M.P. Ayres, C.D. Canham, D.R. Foster, S.L. LaDeau, and T. Weldy. 2016. Nonnative forest insects and pathogens in the United States: Impacts and policy options. Ecological Applications, 0(0), 2016, pp. 1–19. DOI 10.1890/15-1176.1 Recommendations available at www.caryinstitute.org/tree-smart-trade
Posted by Faith Campbell
We welcome comments that supplement or correct factual information, suggest new approaches, or promote thoughtful consideration. We post comments that disagree with us — but not those we judge to be not civil or inflammatory.
On September 25, the DHS Bureau of Customs and Border Protection (CBP) announced that beginning on November 1, the agency would no longer eschew penalizing importers of non-compliant wood packaging until that importer had accumulated five such interceptions in the course of a year.
Beginning November 1, “responsible parties with a documented WPM violation may be issued a penalty under Title 19 United States Code (USC) § 1595a(b) or under 19 USC § 1592.”
As readers of this blog might remember, I have frequently fulminated against the “five strikes” policy. The United States began full implementation of the international standard governing treatment of wood packaging (ISPM#15) 11 and ½ years ago. The U.S. and Canada began requiring China to treat its wood packaging nearly 18 years ago. Nevertheless, numerous shipments containing wood packaging that does not comply with the regulations continue to arrive at our borders – and to bring pests. As of February, only about 30 import shipments (out of nearly 21,000 shipments found to be in violation of ISPM#15 requirements) have received a financial penalty.
shipments of stone or tile are frequently supported by non-compliant wood packaging; photo (c) the Queen by right of Canada (CFIA)
In a blog I posted in February I described the continuing detections of pests in wood packaging. In summary, during Fiscal Years 2010 through 2016, CBP detected nearly 5,000 shipments of wood packaging that harbored a pest in a regulated taxonomic group. The APHIS interception database for the period FYs 2011 – 2016 contained 2,547 records for insect detections on wood packaging. The insects belonged to more than 20 families. A quarter were in the Cerambycid family; 11% were Buprestids. In a study of insect larvae removed from incoming wood packaging from the period April 2012 through August 2016, APHIS scientists evaluated 1,068 insects from 786 separate interceptions of non-compliant wood packaging. The wood packaging in all three datasets came from dozens of countries.
(Remember, the U.S. and Canada do not apply ISPM#15 to wood packaging moving between the two countries. Neither country inspects wood packaging from the other country at even the low rate of inspection applied to wood packaging coming from other countries – so we don’t know how many quarantine pests are moving in this high-volume trade.)
The Bureau of Customs’ action has partially fulfilled one of two recommendations that I made in the February blog. I applaud CBP’s action. However, neither CBP or APHIS has yet prohibited importers with records of repeat violations from using wood packaging – my second recommendation.
Note that the CBP decision applies Customs regulations; USDA has apparently not changed its policy of allowing importers to accumulate five (detected) violations in a calendar year before applying the civil penalties provided by the Plant Protection Act. Why?
We welcome comments that supplement or correct factual information, suggest new approaches, or promote thoughtful consideration. We post comments that disagree with us — but not those we judge to be not civil or inflammatory.
You know that the continuing pest risk associated with imports of wood packaging is among my biggest concerns. See, for example, fact sheets here and blogs here and here.
A new book about the family Cerambycidae (edited by Wang 2017; reference at end of blog) confirms that longhorned beetles continue to be introduced to many countries via this pathway, more than a decade after widespread implementation of the international standard governing wood packaging (ISPM#15). Furthermore, data from several countries confirm that China continues to fall short … but that problems are more widespread.
The Wang book finds that 16 outbreaks of the Asian longhorned beetle (ALB) were detected between 2012 and 2015.
Unless otherwise noted, the information provided here comes largely from the book’s chapter on biosecurity coauthored by Dominic Eyre and Robert A. Haack (see link below). Opinions stated are mine, unless specified otherwise.
In some cases – which I will note – further details are from my earlier posts.
While I think the risk of introduction of highly damaging pests via the wood packaging pathway is well documented in Wang (2017) and other publications, no one can truly quantify this risk because of shortcomings in countries’ data. Available data come primarily from countries’ records of pest “interceptions” – usually at points of entry. However, interception data are inadequate to conclusively establish the lack of a threat for a particular trade or to provide a fair comparison of the relative threat of particular trades. Most interception databases have the following shortcomings (Eyre and Haack are summarizing points made by a third scientist – Lee Humble – in an earlier article):
(1) interception databases are not based on random sampling, which is necessary to measure the “approach” or “infestation” rate;
(2) inspections which find no pests are not recorded, so we cannot know what proportion of incoming shipments are infested;
(3) once inspectors have discovered a quarantine pest in a shipment, the consignments may be destroyed without further inspection, and thus other exotic organisms can be missed;
(4) only a small percentage of individual shipments are inspected; and
(5) organisms often are not identified to species due to difficulty of identifying larvae.
Furthermore,
(1) trade volumes and sources can change rapidly;
(2) the number of consignments inspected varies from year to year in response to national and regional plant health and wider government priorities;
(3) the method and intensity of quarantine inspections can vary within and among countries and as well as over time; and
(4) different proportions of consignments from different trades can be inspected, reflecting the perceived quarantine risks of each trade.
Still, scientists try to analyze the available data because propagule pressure may be the most important factor in determining whether an exotic pest becomes established.
What have they found?
Data from both the United States and Europe document that problems of non-compliance continue in recent years – more than a decade after adoption of ISPM#15.
United States:
Since APHIS interception records began being computerized in 1985, Cerambycidae have been among the most frequently intercepted insect families associated with wood products and packaging. The top five countries for infested shipments during the period 1984 – 2008 were China, Italy, Mexico, Turkey and Spain. A country’s rank is linked in part to import volumes – which are very high for China, Canada, and Mexico. Because the U.S. inspects very limited quantities of wood packaging from Canada, its absence from the top five may be misleading [discussed in my blog from February, here.
Another factor explaining these countries’ rankings is the continued – in fact increasing! – presence of pests in wood packaging accompanying imports of tile and quarry products (e.g., marble, slate). Many of these imports are from Italy, Spain, and Mexico. Interceptions on these imports increased significantly from the mid-1990s to 2008. The increase in these interceptions is most alarming because it shows USDA leaders have not yet taken effective action to curtail this risk, despite its being evident since record-keeping began.
Over the period Fiscal Years 2010 through 2016, the U.S. Bureau of Customs and Border Protection has detected nearly 5,000 consignments in which cases the wood packaging harbored a pest in a regulated taxonomic group. APHIS experts identified 2,500 insects taken from wood packaging during this period; a quarter were Cerambycids. A second APHIS analysis of a subset of the wood packaging-associated insects found examples from 39 countries, including 212 shipments from Europe; 130 shipments from Asia; and 341 shipments from the Americas – almost exclusively Mexico. [These detections are discussed in my blog from February, here.
Europe has had a similar experience.
Interception records included in EUROPHYT show 306 Cerambycidae interceptions on wood packaging over the period 1998 – 2013. The number of interceptions recorded in 2012 and 2013 are double those of all previous years. Each year, the majority are on wood packaging from China.
Most interceptions of ALB (distinct from detections of establishments) have occurred after the shipment cleared border inspection procedures, e.g., in warehouses.
As with the U.S., while the majority of non-compliant shipments are from China, the problem is worldwide: Europe has also found various species of longhorned beetles in wood packaging from various European countries (inside and outside the European Union), other Asian countries, Africa, Australasia, and the Americas.
Austria inspected 451 consignments of stone imports received April 1, 2013 – April 14, 2014. Forty-four consignments (9.8%) were found to be out of compliance with ISPM#15. Live Cerambycidae were found in 38 consignments (8%), including ALB. This finding confirms the widespread awareness that stone imports rank high for non-compliant wood packaging.
Since March 31, 2013, the European Union has required inspection of 90% of consignments of slate, marble, and granite and 15% of consignments of two other categories of stone imports.
CBP agriculture specialists in Laredo, Texas, examine a wooden pallet for signs of insect infestation. [Note presence of an apparent ISPM stamp on the side of the pallet] Photo by Rick PauzaUnited States
As noted by Haack et al. (2014) (reference below), as of 2009, approximately 13,000 containers harboring pests probably enter the U.S. each year. That is 35 potential pest arrivals each day. [This issue is also discussed in the fact sheet and blogs here and here.
The United States has not specified an obligatory inspection rate for such high-risk imports as stone and tile. Instead, it relies on Customs and Border Protection to target import shipments suspected of being out of compliance based on past performance of importers, suppliers, and types of imports.
Several relevant issues are discussed in the blog in February 2017 (second blog linked to above). First, I noted that the U.S. Department of Homeland Security Bureau of Customs and Border Protection – over the seven-year period Fiscal Years 2010 through 2016 – has detected nearly 5,000 cases of wood packaging harboring a pest in a regulated taxonomic group. Comparing the estimate by Haack et al. 2014 with the CBP data indicates that Customs is detecting about 6% of all pest-infested shipments.
Furthermore, about 26% of infested wood pieces detected by CBP were found in wood that was marked as having been treated according to ISPM#15 requirements. What does this mean? Fraud? Accidental misapplication of the treatments? Or are the treatments less effective than hoped? What are USDA and other responsible agencies doing to clarify the causes?
CBP staff reported that only about 30 import shipments (out of nearly 21,000 shipments found to be in violation of ISPM#15 requirements) have received a financial penalty. How can USDA and Customs officials justify this failure to enforce the regulations?
What Can Be Done to Close Down the Wood Packaging Pathway
I suggest that our goal should be to hold foreign suppliers responsible for complying with ISPM#15. One approach is to penalize violators. APHIS and Customs might
Prohibit imports in packaging made from solid wood (boards, 4 x 4s, etc.) from foreign suppliers which have a record of repeated violations over the 11 years ISPM#15 has been in effect (17 years for exporters from Hong Kong & mainland China). Officials should allow continued imports from those same suppliers as long as they are contained in other types of packaging materials, including plastic, metals, or fiberboards.
Fine an importer for each new shipment found to be out of compliance with ISPM#15 in cases when the foreign supplier of that shipment has a record of repeated violations.
There would need to be a severe penalty to deter foreign suppliers from simply changing their names or taking other steps to escape being associated with their violation record.
At the same time, the agencies should work with non-governmental organizations and importers to promote creation of an industry certification program that would recognize and reward importers who have voluntarily undertaken actions aimed at voluntarily exceeding ISPM#15 requirements so as to provide a higher level of protection against invasive species that would otherwise potentially be introduced into the United States.
What You Can Do
Tell your member of Congress and Senators that you are worried that our trees are still being put at risk by insects arriving in wood packaging. Ask them to urge the USDA Secretary Sonny Perdue to take the actions outlined above in order to curtail introductions of additional tree-killing pests.
Talk to your friends and neighbors about the threat to our trees. Ask them to join you in communicating these concerns to their Congressional representatives and Senators.
Write letters to the editors of your local newspaper or TV news station.
Use your knowledge about pests threatening trees in your state or locality in your communications!
Other Introduction Pathways for Cerambycids
tree removals in Tukwilla, WA to eradicate citrus longhorned beetle; photo by Washington State Department of Agriculture
Plants for planting
Other studies have confirmed that importation of living plants (called by regulators “plants for planting”) is a high-risk pathway for introducing tree-killing pests. See the Eyre and Haack chapter for a summary.
This is as true for highly damaging Cerambycids as for other types of plant pests. One of the most damaging is the citrus longhorned beetle (CLB) (Anoplophora chinensis). CLB [https://www.dontmovefirewood.org/invasive-species/] poses an even greater threat to North American forests than ALB – it has a wider host range and climate-matching models show that it could establish across most of the United States. CLB were detected in a nursery in Tukwilla, Washington, in 2001; the pest was eradicated. Nine CLB outbreaks have been detected in Europe; three are considered eradicated (Eyre & Haack 2017).
Eyre and Haack (2017) report that in Europe of the 455 Cerambycidae intercepted over the period 1998 – 2013, 54 were on imported in living plants. These included probably 49 citrus longhorned beetle (CLB). Most were detected primarily on maple nursery stock that originated China (32), with smaller numbers from other countries, including Netherlands (8), and Italy (where CLB has been established).
New Zealand has intercepted 74 CLB on plants for planting over the 28 year period 1980 – 2008. One third of this total was intercepted in 2008.
Authorities’ Responses (or lack thereof)
Europe
Since 2012, the European Union has required that 10% of CLB host plants imported into the European Union should be destructively sampled (that is, dissected to see whether insects are present internally).
This requirement supplements a broader requirement that plants for planting be treated as a high risk commodity. Member states are required to inspect all incoming P4P consignments. This requirement is, however, undermined by much more lenient requirements regarding movement of plants among EU member states – some genera are not regulated … others are controlled by Plant Passports – an industry-led scheme. [For more on this issue, see my blog from October 2016 here.
United States
APHIS issued a Federal order tightly restricting imports of CLB hosts from Europe in 2013 – four years after a CLB outbreak was detected in a part of the Netherlands which is a center for the production of hardy ornamental nursery stock for European and probably American markets.
APHIS proposed to revise its overall plant importation regulations (the “Q-37 regulations) to rely more on integrated management by the exporting nurseries in contrast to port inspections. This rulemaking has stalled. [See my blog about this here.]
Finished Wood Products
While no country is keeping comprehensive records, finished wood products have transported longhorned beetles. Eyre and Haack (2017) concluded that upholstered furniture presents one of the highest risk among the finished wood products – partly because imports are rising rapidly, partly because insect-damaged wood can be hidden under the upholstery. New Zealand found that some Asian manufacturers place good quality wood on visible surfaces and poor quality timber (insect damaged and bark covered) in internal sections. Officials inspected 49 couches and found that 30 had wood with bark, 19 had insect contaminants, and 32 had visible insect damage. Fungal samples were isolated from 11 of the couches. They found 4 longhorned beetles.
References
Wang, Q. (Ed.). 2017. Cerambycidae of the world: biology and pest management. Boca Raton, FL: CRC Press
We welcome comments that supplement or correct factual information, suggest new approaches, or promote thoughtful consideration. We post comments that disagree with us — but not those we judge to be not civil or inflammatory.
Numbers of non-native pests in counties of the 49 continental states; Map prepared by Andrew Liebhold, USFS in 2014. More recent introductions are not represented; nor are insects native to some part of North America
Currently, the Northeast and Midwest have the highest number of non-native, tree-killing insect and pathogen species (see map above). However, Pacific coast states have two-thirds the numbers of pest species of the Northeast – and are catching up. Two articles modeling the likelihood of new pest introductions point to the particular vulnerability of the Pacific Coast states – especially California – to pest introductions from Asia.
Koch et al. 2011 (see reference at the end of the blog) utilized various sources of information about volumes of imports likely to be associated with wood-boring pests — stone; raw wood and wood products (including crates & pallets); metals; non-metallic minerals; auto parts; etc. From this, the authors estimated both a nationwide establishment rate of wood-boring forest insect species and the likelihood that such insects might establish at more than 3,000 urban areas in the contiguous U.S. While their estimate was based on 2010 imports, they also projected rates for 2020.
See my blog from March 10 for various scientists’ estimates of the overall, nationwide rate of introduction. Koch et al. estimated the nation-wide introduction rate at between 0.6 and 1.89 forest insects and pathogen species per year for the period 2001–2010 and 0.36 and 1.7 species per year for 2011–2020. In other words, we should expect a new alien forest insect species to become established somewhere in the United States every 2–3 years. If one-tenth of these new introductions turn out to cause significant damage, then we can expect a “significant” new forest pest every 5–6 years.
Pacific coast states – especially California – are at highest risk.
Koch et al. evaluated the introduction risk for 3,126 urban areas across the country. The metropolitan area with the highest risk is Los Angeles–Long Beach–Santa Ana, California. For both 2010 and 2020, the predicted rates for a new pest establishing there is every 4–5 years.
Looking ahead to 2020, the situation worsens for three California metro areas – Los Angeles–Long Beach–Santa Ana; San Diego; and Riverside-San Bernardino. At San Francisco-Oakland, the predicted establishment rates remain steady. Most of the rest of the top 25 urban areas show decreases in establishment rate between 2010 and 2020.
This rising risk to California urban areas is driven by the growth of imports from Asia. For the four California urban areas, the establishment rate of Asian species is projected to increase 6–8% between 2010 and 2020. The Los Angeles–Long Beach–Santa Ana area could potentially expect the establishment of an alien forest insect species originating specifically from Asia alone (not the entire world) every 4–5 years.
[The polyphagous and Kuroshio shot hole borers are examples of recently introduced pests from Asia. Both are described, inter alia, here; a distribution map for PSHB is available here.]
Koch et al. note that the Los Angeles metropolitan area has a dense human population with corresponding high demand for goods and materials, so a substantial proportion of imports clearing the port remains in the areas. Furthermore, widespread planting of non-native plants provides a range of potential hosts that can support invaders that would not otherwise become successfully established.
A second source also indicates a heightened risk to Pacific Coast states. Yemshanof et al. used similar modeling techniques to evaluate the risk of tree pest introductions to Canada … and to the U.S. in the form of transshipped goods. (See my earlier blog.)
The Yemshanof et al. model showed that 8% of all forest pests introduced to the U.S. on imported wood or wood packaging — as estimated by Koch et al. — would come through goods transshipped through Canada. The risk is highest to the Pacific Coast states since they are the most likely to receive Asian goods transiting through Canada.
Note that the phytosanitary agencies in both the U.S. and Canada proposed in 2010 that wood packaging originating in one of the countries and shipped to the other be required to meet the international regulations under ISPM#15. However, APHIS was unable to adopt this regulation under the Obama Administration, and such an action seems even less likely under the Trump Administration. Canada is unlikely to adopt the new rules without a coordinated U.S. action.
Southern California also imports lots of plants – another pathway for pest introductions.
Koch et al. suggest that authorities use these models to prioritize border control efforts (e.g., commodity inspections), post-border surveillance, and rapid-response measures. I see some problems with these suggestions. First, enhanced commodity inspections are not likely to measurably diminish the risk of introduction to the region. Second, rapid-response measures require both increased funds – which are expected to decrease; and political will. I have blogged several times about California’s decisions to not implement official, regulatory responses to recently detected pests.
Instead, people in the region should actively build alliances and press their regional political leaders – governors, mayors, senators, members of Congress – to demand that the U.S. Department of Agriculture and the Congress adopt policies that will strengthen protection for the region’s trees.
New pest detected in California!
California authorities have detected a new woodboring beetle – the olive wood borer (Phloeotribus scarabaeoides). It was detected in an olive tree in a grape vineyard in Riverside County. This is the first detection of the species in the Western Hemisphere. Known or suspected hosts include several trees in the olive family (Oleaceae), including olive trees, privet, ash, and common lilac; as well as oleander (Apocynaceae).
Since this new pest is native to the Mediterranean region, it does not appear to be an example of the risk to California from Asia … The source (Diagnostic Network News; see below) does not speculate on the pathway by which the introduction occurred.
What Can We Do?
Ask your state’s Governor to
Communicate to the USDA Secretary the need to amend policies & regulations
(Coordinate this effort with governors of other states.)
Put forest pest issue on the agenda of National Governors’ Association
Ask your state’s Congressional delegation to pressure USDA Secretary to amend policies and regulations
Communicate concern about these pests to the media — and propose solutions.
Ask your state’s agricultural and forestry agency heads to
Ask their national associations to support proposals to USDA Secretary & Congress. These associations include
National Association of State Departments of Agriculture (NASDA)
National Association of State Foresters (NASF) or its Western regional group, the Council of Western State Foresters
Communicate to the media both the agency’s concern about tree pest threats and proposed solutions.
We can also act directly.
Ask mayors and officials of affected towns and counties to
Push proposals at regional or National Conference of Mayors or National Association of Counties
Instruct local forestry staff to seek support of local citizen tree care associations, regional and national associations of arborists, Arbor Day & “Tree City” organizations, Sustainable Urban Forest Coalition, etc.
Reach out to local media with a message that includes descriptions of policy actions intended to protect trees — not just damage caused by the pests
Ask stakeholder organizations of which you are a member to speak up on the issue and support proposed solutions; e.g.,
Professional/scientific associations
Wood products industry
Forest landowners
Environmental NGOs
Urban tree advocacy & support organizations
Encourage like-minded colleagues in other states to press the agenda with their state & federal political players, agencies, & media.
Communicate to the media both your concern about tree pest threats and proposed solutions.
What Specific Actions Should We Suggest be Taken?
I suggest a coordinated package. However, you might feel more comfortable selecting a few to address each time you communicate with a policymaker. Choose those on which you have the most expertise; or that you think will have the greatest impact.
Make specific proposals, not vague ideas (see below for suggestions)
Always include information about how the pests arrive/spread (pathways such as imports of crates & pallets, or woody plants for ornamental horticulture) and what we can do to clean up those pathways (Don’t just describe the “freak of the week”)
Always point out that the burden of pest-related losses and costs falls on ordinary people and their communities. (Aukema et al. 2011 provides backup for this at the national level; try to get information about your state or city.)
We need to restore a sense of crisis to prompt action – but not leave people feeling helpless! We need also to bolster understanding that we have been and can again be successful in combatting tree pests.
Specific actions that will reduce risk that pests pose to our trees:
Importers switch from packaging made from solid wood (e.g., boards and 4”x4”s) to packaging made from other materials, e.g., particle boards, plastic, metal …
Persuade APHIS to initiate a rulemaking to require importers to make the shift. This can be done – although international trade agreements require preparation of a risk assessment that justifies the action because it addresses an identified risk (see my earlier blogs about wood packaging).
Create voluntary certification programs and persuade major importers to join them. One option is to incorporate non-wood packaging into the Department of Homeland Security Bureau of Customs and Border Protection’s (CBP) existing Customs-Trade Partnership Against terrorism (C-TPAT) program.
Tighten enforcement by penalizing shipments in packaging that does not comply with the current regulations
Persuade CBP and/or USDA to end current policy under which no financial penalty is imposed until a specific importer has been caught five times in a single year with non-compliant wood packaging. APHIS has plenty of authority to penalize violators under the Plant Protection Act [U.S.C. §7734 (b) (1)].
Restrict imports of woody plants that are more likely to transport pests that threaten our trees
In 2011, APHIS adopted regulations giving it the power to temporarily prohibit importation of designated high-risk plants until the agency has carried out a risk assessment and implemented stronger phytosanitary measures to address those risks. Plants deserving such additional scrutiny can be declared “not authorized for importation pending pest risk assessment,” or “NAPPRA”. A list of plants posing a heightened risk was proposed nearly 4 years ago, but it has not been finalized – so imports continue. APHIS should revive the NAPPRA process and utilize prompt listing of plants under this authority to minimize the risk that new pests will be introduced.
APHIS should finalize amendments to the “Q-37” regulation (proposed nearly 4 years ago) that would establish APHIS’ authority to require foreign suppliers to implement integrated programs to minimize pest risk. Once this regulation is finalized, APHIS could begin negotiating agreements with individual countries to adopt systems intended to ensure pest-free status of those plant types, species, and origins currently considered to pose a medium to high risk.
Strengthen early detection/rapid response programs by
Providing adequate funds to federal & state detection and rapid response programs. The funds must be available for the length of the eradication program – often a decade or more.
Engage tree professionals & citizen scientists more effectively in surveillance programs.
SOURCES
Koch, F.H., D. Yemshanov, M. Colunga-Garcia, R.D. Magarey, W.D. Smith. Potential establishment of alien-invasive forest insect species in the United States: where and how many? Biol Invasions (2011) 13:969–985
Western Plant Diagnostic Network First Detector News. Winter 2017. Volume 10, Number 1.
Yemshanov, D., F.H. Koch, M. Ducey, K. Koehler. 2012. Trade-associated pathways of alien forest insect entries in Canada. Biol Invasions (2012) 14:797–812
We welcome comments that supplement or correct factual information, suggest new approaches, or promote thoughtful consideration. We post comments that disagree with us — but not those we judge to be not civil or inflammatory.
Several analyses seek to quantify the risk that new tree-killing pests will be introduced to North America. They use different data sources and assumptions, and reach somewhat different conclusions. But all agree that the risk remains high, and the consequences of such introductions are dire.
I have relied on the Aukema et al. 2010 (see references at the end of the blog) and Haack et al. 2014 studies in past blogs. Aukema et al. 2010 looked at the probable dates of introduction for established insects and pathogens to determine that over 150 years, from 1860 to 2006, damaging forest insect and pathogen species were detected at an average rate of between 0.47 and 0.51 species per year. This translates to one damaging insect or pathogen every 2.1 to 2.4 years. The frequency of detection of high-impact forest pests rose sharply after 1990; beginning that year, detections of high-impact forest pests averaged 1.2 per year, nearly three times the rate of detections in the previous 130 years.
In 2013, 25 million shipping containers entered the U.S. An estimate from more than a decade ago is that wood packaging is used in about half of these containers. Haack et al. (2014) has estimated that 0.1% (1/10th of 1%) of the wood packaging in more than 12 million shipping containers entering the country each year is infested with quarantine pests. That works out to nearly 13,000 containers harboring pests that probably enter the country each year. That is 35 potential pest arrivals per day.
Leung et al. 2014 concluded that continuing to implement the international standard — ISPM#15 — at the efficacy level described by Haack et al. would result in a tripling of the number of non-native wood-boring insects introduced into the U.S. by 2050.
Koch et al. 2011 have also attempted to determine the current rate of introduction of wood-boring insects. They also sought to evaluate the introduction risk for specific metropolitan areas.
Koch et al. utilized various sources of information about volumes of imports of goods likely to be associated with wood-boring pests (e.g., raw wood and wood products; and stone, metals, non-metalic minerals, auto parts, etc., contained in wooden crates and pallets) to estimate both a nationwide establishment rate of wood-boring forest insect species and the likelihood that such insects might establish at more than 3,000 urban areas in the contiguous US.
They estimated the nationwide rate of introduction of wood-boring pests at between 0.6 and 1.89 forest pest species per year for the period 2001–2010. Even the more conservative estimates points to establishment of a new alien forest insect species somewhere in the US every 2–3 years. If one accepts the ‘‘tens rule’’ – that one out of ten new introductions proves to have substantial effects, then one expects establishment of a significant new pest on average every 5 – 6 years. The authors note that the establishment of at least four ecologically and/or economically significant alien forest insects during the past 20–25 years – emerald ash borer, Asian longhorned beetle, Sirex woodwasp, and redbay ambrosia beetle – fits the model’s conclusion. [All of these pests are described in the Gallery of Pests posted here.]
The Aukema et al. estimate for introductions of “high impact” pests during the period after 1990 – 1.2 per year – is in the middle of the Koch et al. estimate for wood-borers, but higher than the Koch et al. estimate for “significant” pests.
Koch et al. estimated a lower rate of introductions between 2010 and 2020 – between 0.36 and 1.7 species per year. The Haack et al. and Leung et al. analyses would seem to contradict this expectation. Also, the findings of Seebens et al. (see my blog from earlier this week) contradicts any expectation that introductions will soon decline as a result of depletion of the pool of possible pests in origin countries.
Koch et al. analyzed data on imports of relevant commodities from all source regions to determine the introduction risk for 3,126 urban areas in the country. The urban area at greatest risk was Los Angeles–Long Beach–Santa Ana, California. The predicted introduction rate for both 2010 and 2020 for this metropolis was establishment of a new alien forest insect species every 4–5 years. The port of New York-Newark came in second, with a predicted establishment rate of one every 8–9 years. Houston ranked third; its predicted establishment rate was one every 13–15 years. All other urban areas were at substantially lower risk – a new introduction every 24 years.
Looking ahead to the decade 2010 to 2020, Koch et al. found that three California metro areas – Los Angeles–Long Beach–Santa Ana; San Diego; and Riverside-San Bernardino – would be exposed to increased establishment rates driven by the growth of imports from Asia.
Risk To Canada
Yemshanof et al. 2011 applied the Koch et al. methodology to evaluate the risk to Canada. Reflecting the lower volume of imports entering Canada compared to the U.S., they found a lower nationwide entry rate for Canada – 0.338 new forest insect species per year vs. the Koch et al. estimate of 1.89 for the U.S. Evaluating individual urban areas, they found the greatest risks to the Greater Toronto and Greater Vancouver areas. Moderate-sized cities near ports, major markets, or U.S.-Canada border crossings – transportation hubs – were also at heightened risks.
Canada as Pest Pathway to U.S.
Yemshanof et al.’s model indicates that 8% of all tree pests entering the U.S. as estimated by Koch et al., come through goods transshipped through Canada. The risk is highest to the Pacific Coast states since they are the most likely to receive Asian goods transiting through Canada. Note that the U.S. and Canada have proposed requiring that wood packaging originating in one of the countries and shipped to the other should be included under the ISPM#15 regulation. However, APHIS was unable to adopt this regulation under the Obama Administration, and such an action seems even less likely under the Trump Administration.
Neither study included plant imports, which are another very important pathway for introduction of tree-killing pests, especially pathogens.
SOURCES
Haack 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
Koch, F.H., D. Yemshanov, M. Colunga-Garcia, R.D. Magarey, W.D. Smith. 2011. Potential establishment of alien-invasive forest insect species in the United States: where and how many? Biol Invasions (2011) 13:969–985
Leung, 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
Yemshanov, D., F.H. Koch, M. Ducey, K. Koehler. 2012. Trade-associated pathways of alien forest insect entries in Canada. Biol Invasions (2012) 14:797–812
Posted by Faith Campbell
We welcome comments that supplement or correct factual information, suggest new approaches, or promote thoughtful consideration. We post comments that disagree with us — but not those we judge to be not civil or inflammatory.
ALB pupa; Thomas B. Denholm, New Jersey Department of Agriculture; bugwood.org
As I have noted in earlier fact sheets and blogs, wood packaging (crates, pallets, etc.) has been a major pathway for introductions of highly damaging wood-boring pests since at least the early 1990s. (See Figure 2a in Aukema et al. 2010; reference given at end of blog.)
This rise in introductions followed the rapid increase in use of shipping containers – as described in Levinson’s book The Box (reference below). Levinson notes that shipping capacity increase fourfold during the decade of the 1970s, reaching 10 million tons in 1980. (See also my blog from August 2015 here). A second factor was the U.S. opening trade with China in 1979. Since in those years – before establishment of more sophisticated detection tools – a pest was often present for close to a decade before being detected, it is not surprising that detections of woodboring pests began their rise around 1990.
February 2017 marks 11 years since the international standard (ISPM#15) was put into effect by the United States and 17 years after the U.S. and Canada began requiring China to treat its wood packaging. Nevertheless, numerous shipments containing wood packaging that does not comply with the regulations continue to arrive at our borders – and to bring pests.
A study by scientists and economists (Haack et al. 2014; reference below) analyzed detection data from the U.S. and other countries in order to calculate the reduction in pest risk associated with wood packaging following adoption of ISPM#15. They concluded that one tenth of one percent of the wood packaging entering the U.S. after adoption of ISPM#15 still contained a tree-killing pest. This sounds like a small risk. However, the U.S. imported approximately 25 million shipping containers in 2013 – and presumably similar numbers in more recent years. It has been estimated in the past that wood packaging is used in just over half of these containers. Therefore, even if merely 1/10th of 1% of the wood packaging in these shipments contained a tree-killing pest, 13,000 containers harboring pests probably enter the country each year. That is 35 potential pest arrivals each day.
Interception records compiled by USDA APHIS and the DHS Bureau of Customs and Border Protection clearly show that wood packaging infested with pests continued to arrive in recent years – including in 2016.
Over a period of seven years – Fiscal Years 2010 through 2016 – CBP detected more than 20,700 shipments with wood packaging that did not comply with ISPM#15. While most of the non-compliances represented wood packaging that lacked the required mark showing treatment per ISPM#15, in nearly 5,000 cases the wood packaging actually harbored a pest in a regulated taxonomic group (see Customs presentation at the Continental Dialogue here).
Customs inspectors at 11 ports (listed at end of blog) have been sending intercepted wood packaging containing insect larvae to APHIS for study. APHIS has also sent to me its record of interceptions for the period FYs 2011 – 2016.
The APHIS interception database contained 2,547 records for insect detections. The insects belonged to more than 20 families. Families with the highest numbers of detections were Cerambycids – 25% of total; Curculionidae – 23% (includes Dendroctonus, Ips, Orthotomicus, Scolytinae, Xyleborus, Euwallacea); Scolytidae – 17% (includes true weevils such as elm bark beetles); Buprestids – 11%; and Bostrichidae – 3%. Not all of the insects in these groups pose a threat to North American plant species.
piece of wood packaging with Cerambycid larva; detected in Oregon
The samples sent by CBP to APHIS are limited largely to the families Cerambycidae (the family containing the Asian longhorned beetle) and Buprestidae (the family containing the emerald ash borer). This dataset contains 1,068 insects, obtained over the period April 2012 through August 2016 from 786 separate interceptions of non-compliant wood packaging. The sample is not from a random set of ports – four of the seven entry points are on the Mexican border, and the proportion was even higher in the early years of the study.
The APHIS interception database reports pests detected in wood packaging from dozens of countries. The countries of origin with the highest numbers of shipments detected to have pests present were Mexico, China, Italy, and Costa Rica. These numbers reflect in part import volumes. The U.S. imports huge volumes of goods from both Mexico and China. (Our second largest trade partner is Canada; the U.S. and Canada have exempted wood packaging moving between the two countries from the requirement that it comply with ISPM#15. Neither country inspects wood packaging from the other country at even the low rate of inspection applied to wood packaging coming from Mexico or overseas.)
The CBP-APHIS database includes pests found in wood packaging from 39 countries, including 212 shipments from Europe; 130 shipments from Asia; and 341 shipments from the Americas – almost exclusively Mexico.
APHIS analysts point out that the pests from Mexico might pose a lower risk since some proportion of them are probably species shared between our two countries. (However, several woodborers from Mexico are killing trees in the U.S. – e.g., goldspotted oak borer, walnut twig beetle, and soapberry borer. These species are described briefly here. These insects were probably introduced to vulnerable parts of the U.S. in firewood rather than wood packaging.)
As always (see the briefs here as well as various articles by Haack and Cavey), imports of heavy objects are associated with wood packaging found to be infested with insects: metal and machine parts, tiles, decorative stone. Imports of fruits and vegetables rank high because of the large number of interceptions in wood packaging from Mexico.
Comparing the estimate by Haack et al. 2014 with the CBP data indicates that Customs is detecting about 6% of all pest-infested shipments. I do not believe that increasing the inspection workforce and effort will result in substantial improvement in this rate.
On average, 26% of infested wood pieces detected by CBP were found in wood that had been treated according to ISPM#15 requirements (if we believe the ISPM#15 stamp on the wood). Does this indicate fraud? Or is the problem accidental misapplication of the treatments? Or are the treatments less effective than hoped? APHIS researchers have found that larvae from wood subject to methyl bromide fumigation were more likely to survive to adulthood than those intercepted in wood that had been heat treated. Does this indicate that methyl bromide fumigation is a less effective treatment?
CBP staff reported that only about 30 import shipments (out of nearly 21,000 shipments found to be in violation of ISPM#15 requirements) have received a financial penalty. CBP staff cite two reasons for the low penalty rate:
USDA policy requires that an importer be caught 5 times in a year with non-compliant wood packaging before authorizing a fine; and
APHIS has not designated SWPM as a high-risk commodity
What Can Be Done to Slow or Eliminate this Pathway?
Our goal should be to hold foreign suppliers responsible for complying with ISPM#15. One approach is to penalize violators. APHIS and Customs might
Prohibit imports in packaging made from solid wood (boards, 4 x 4s, etc.) from foreign suppliers which have a record of repeated violations over the 11 years ISPM#15 has been in effect (17 years for exporters from Hong Kong & mainland China). Officials should allow continued imports from those same suppliers as long as they are contained in packaging made from other types of materials, including plastic, metals, fiberboards …
Fine an importer for each new shipment found to be out of compliance with ISPM#15 in cases when the foreign supplier of that shipment has a record of repeated violations.
There would need to be a severe penalty to deter foreign suppliers from simply changing their names or taking other steps to escape being associated with their violation record.
At the same time, the agencies should work with NGOs and importers to promote creation of an industry certification program that would recognize and reward importers who have voluntarily undertaken actions aimed at voluntarily exceeding ISPM#15 requirements so as to provide a higher level of protection against invasive species that would otherwise potentially be introduced into the United States.
What You Can Do
Tell your member of Congress and Senators that you are worried that our trees are still being put at risk by insects arriving in wood packaging. Ask them to urge the new Secretary of Agriculture (Sonny Perdue, former governor of Georgia) to take the actions outlined above in order to curtail introductions of additional tree-killing pests.
Talk to your friends and neighbors & civic organizations about the threat to our trees. Ask them to join you in communicating these concerns to their Congressional representatives and Senators.
Write letters to the editors of your local newspaper or TV news station.
Use your knowledge about pests threatening trees in your state or locality in your communications!
Ports that have sent specimens to APHIS lab: Seattle, Long Beach, San Diego, Laredo, Hildago, Houston, Miami, Port Everglades, Chicago, Detroit
References
Aukema, J.E., D.G. McCullough, B. Von Holle, A.M. Liebhold, K. Britton, & S.J. Frankel. 2010. Historical Accumulation of Nonindigenous Forest Pests in the Continental United States. Bioscience. December 2010 / Vol. 60 No. 11
Haack, R. A., K. O. Britton, E. G. Brockerhoff, J. F. Cavey, L. J. Garrett, M. Kimberley, F. Lowenstein, A. Nuding, L. J. Olson, J. Turner, and K. N. Vasilaky. 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:e96611.
Levinson, M. The Box: How the Shipping Container Made the World Smaller and the World Economy Bigger Princeton University Press 2008
We welcome comments that supplement or correct factual information, suggest new approaches, or promote thoughtful consideration. We post comments that disagree with us — but not those we judge to be not civil or inflammatory.
Sixteen scientists and policy analysts (including me) have published a new study reviewing recent work on numbers, pathways and impacts of non-native, tree-killing insects and pathogens. I encourage you to read the article. It provides a concise and compelling overview of the threat to our wildland, rural, and urban forests from non-native insects and diseases and proposes some thought-provoking solutions.
Current policies for preventing introductions have reduced the numbers of pests introduced via the various pathways (e.g., wood packaging and horticultural plants – but not sufficiently to counter pests’ rising opportunities for introduction resulting from burgeoning global trade. [Emphasis mine.]
At the current efficacy of implementing the international regulations governing wood packaging [ISPM #15] ( Haack et al., 2014), and given growing trade, Leung et al. 2014 project that by 2050 – just 35 years from now – up to three times as many wood-boring insects may be introduced to the U.S. as are currently here.
(I discussed this high risk in blogs posted at this site on July 15 and August 22, 2015.)
The new paper presents several options for improving prevention. These include: measures to ensure exporters ship “clean” plants and wood packaging; post-entry quarantines to raise the likelihood that pests will be detected; placing all genera of North American woody plants on USDA’s NAPPRA list of genera not currently approved for import and awaiting risk assessment; and improved surveillance and eradication programs. We also note the importance of improving data collection and allowing researchers outside USDA access to those data to support independent evaluation of policy’s effectiveness.
As Aukema et al. demonstrated six years ago, non-native forest insects have accumulated in U.S. forests at a steady rate of about 2.5 per year over the last 150 yrs. While the rate of introduction has not changed, the types of insects introduced have. In the 20th Century, plant-associated insects dominated the introductions. In recent years wood-boring insects associated with wood packaging materials have dominated. Some of these wood-borers also are highly damaging! (See emerald ash borer, redbay ambrosia beetle/laurel wilt, and polyphagous shot hole borer/Fusarium here). Lack of information precludes a similar analysis for pathogens; although we all know that the 20 or so high-profile pathogens cause great devastation – see descriptions here.
The whole country is at risk; although the highest numbers of tree-killing insects and pathogens are established in the Northeast and Midwest, Pacific Coast states are catching up (and certainly already have their share of devastating insects and pathogens). See the map below. You can check the pests in your state by visiting the interactive map here .
map developed by USFS; published in Aukema et. al 2010.
Our new article notes that these non-native pests are the only disturbance agent that has effectively eliminated entire tree species or genera from U.S. forests in the span of decades. Follow-on effects include alterations of ecosystem functions and huge costs to various stakeholders, especially residents and governments of (sub)urban areas.
These impacts can persist for centuries as a result of altered species composition, which affects multiple trophic levels.
We followed Aukema et al. 2011’s results in estimating the direct annual economic impact of non-native forest insects to be at least: $2 billion in municipal government expenditures, $1.5 billion in lost residential property values, and $1 billion in homeowner expenditures for tree removal and replacement or treatment. These costs and losses contrast with the paltry $216 million estimated in federal government expenditures.
Aukema et al. 2011 noted that these expenses cannot be summed across cost categories because of the potential for double-counting. We note that these figures are probably underestimates for several reasons. They did not include the introduced diseases such as sudden oak death. Nor do they include pests detected recently, such as the polyphagous shot hole borer. Finally, our paper excluded consideration of insects or pathogens native to some part of North America, such as the goldspotted oak borer. (For more information about these organisms, consult the write-ups here.)
As our article notes, the billions of dollars in annual economic damages (and un-quantified ecological impacts) are economic externalities. That is, the importers who benefit from the economic activity do not pay directly for preventing or responding to the associated pest introductions.
The article discusses several policy options that we believe would greatly reduce unacceptable risks. These options include several bold actions:
Require importers to switch from packaging made from wooden boards to packaging made from materials other than solid wood (fiberboards ok). This change is both highly protective and potentially cost-effective. Such a switch would have to be justified under the terms of international trade agreements – but given the high levels of damage caused by wood-boring pests, I don’t think that hurdle is insurmountable.
Greatly strengthen measures aimed at preventing pest introduction on imports of plants. One step would be restricting imports of all genera of “woody” plants native to North America by designating them as “not authorized for importation pending pest risk assessment” (NAPPRA). Another protective step would be to promptly finalize the Q-37 revision proposed by USDA in April 2013 and immediately initiate negotiations with principal foreign suppliers of temperate climate woody vegetation to implement the pest-minimization procedures contained in that revised regulation, as well as in ISPM#36.
Other options discussed are straight-forward and simpler:
Tighten enforcement of existing regulations by ending the practice of allowing an importer to be detected five times in a year with wood packaging that does not comply with regulatory requirements before imposing a penalty. When a new year starts, that importer gets a “clean slate”! Is this how agencies enforce regulations that they are serious about?
Expand efforts to assist trade partners in adopting clean trade measures.
Expand and integrate surveillance programs for new pest outbreaks, and providing timely and adequate funding for emergency eradication efforts.
SOURCES
Aukema, J.E., B. Leung, K. Kovacs, C. Chivers, K. O. Britton, J. Englin, S.J. Frankel, R. G. Haight, T. P. Holmes, A. Liebhold, D.G. McCullough, B. Von Holle.. 2011. Economic Impacts of Non-Native Forest Insects in the Continental United States PLoS One September 2011 (Volume 6 Issue 9)
Aukema, J.E., D.G. McCullough, B. Von Holle, A.M. Liebhold, K. Britton, & S.J. Frankel. 2010. Historical Accumulation of Nonindigenous Forest Pests in the Continental United States. Bioscience. December 2010 / Vol. 60 No. 11
Haack, R. A., K. O. Britton, E. G. Brockerhoff, J. F. Cavey, L. J. Garrett, M. Kimberley, F. Lowenstein, A. Nuding, L. J. Olson, J. Turner, and K. N. Vasilaky. 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:e96611.
Leung, B., M. R. Springborn, J. A. Turner, and E. G. Brockerhoff. 2014. Pathway-level risk analysis: the net present value of an invasive species policy in the US. Frontiers in Ecology and the Environment 12:273-279.
EAB risk to Oregon & Washington
CBP inspecting wood packaging; CBP photo
shipment of decorative stone with wood packaging
