Category: forest pest insects

ISPM#15 – The Stamp is Not Effective as a Clue to Whether Wood Packaging is Pest-Free

For more than a decade, most countries in the world have required that crates, pallets, spools, and dunnage made from wood be treated in accordance with the requirements of the International Standard for Phytosanitary Protection (ISPM)#15 that this treatment be certified by applying an approved stamp to the wood. The goal of the program is to “reduce significantly the risk of introduction and spread of most quarantine pests that may be associated with that material.”

However, experience and studies in both the United States and Europe demonstrate that the ISPM#15 stamp is not a reliable indicator of whether the wood packaging is pest-free.

1) In the United States, over a period of nine years – Fiscal Years 2010 through 2018 – U.S. Customs and Border Protection (CBP) detected 9,500 consignments harboring a pest in a regulated taxonomic group. Of the shipments found with infested wood packaging, 97% bore the ISPM#15 mark (See Harriger reference at the end of the blog). The wood packaging was from nearly all trading countries. 2) In the past two years, CBP inspectors have repeatedly found pests in dunnage bearing the ISPM#15 mark – as reported by U.S. importers of “break bulk” cargo into Houston. While most of the criticism of non-compliant wood packaging refers to countries in Asia and the Americas, at least one of the Houston importers obtains its dunnage in Europe.

3) In Europe, a two-year intensive survey of wood packaging associated with shipments of stone from China to the 28 European Union countries over the period 2013-2016 again found that 97.5% of consignments found to harbor pests bore the ISPM#15 mark (Eyre et al. 2018). The scientists concluded that the ISPM-15 mark was of little value in predicting whether harmful organisms were present. (Eyre et al. 2018, p. 712)

As I have noted in previous blogs and policy briefs, the only in-depth study of the “approach rate” of pests in wood packaging, based on data which is now a decade old, found that 0.1% of incoming wood packaging transported a regulated pest (Haack et al. 2014). Given current trade volumes, as many as 17,650 containers per year (or 48 per day) transporting tree-killing insects might be entering the U.S. (My calculation of this estimate is explained in the blog on “risks of introduction” here.)

The Haack study excluded imports from Mexico, Canada, and China. The first and third countries have records of poor compliance with ISPM#15 requirements, so the “approach rate” for all incoming shipments might well have been higher.

The study of European imports focused on shipments of stone from China – which were deliberately chosen to represent types of imports presenting a high risk of transporting pests. Across Europe, over the four-year period, quarantine pests were detected in 0.9% of the consignments – somewhat higher than the U.S. number, as could be expected. However, there were large variations among participating countries’ findings. Austria and France found 6.95% of consignments inspected were infested, while half of European Union countries found none!

These differences demonstrate the importance of thorough inspections.

The data also indicate that the problem is not decreasing. Austria detected pests in nearly one-fifth (19.6%) of inspected shipments in 2016 – the final year of the study! However, during that same year, only 1.5% of wood packaging lacked the ISPM#15 mark.

So How Should the International Phytosanitary Community React to This Failure?

Data cited in numerous studies indicate that ISPM#15 has probably succeeded in reducing the presence of pests in wood packaging. This progress is good – but insufficient. Our forests need further reductions.

In the meantime, however, the international standard has demonstrably failed to provide a secure method to evaluate the pest risk associated with wood packaging accompanying any particular shipment. The presence of the stamp on pieces of wood packaging does not reliably show that the wood is pest-free. Officials need to determine why. Is it fraud? That would mean deliberately placing the stamp on wood that had not been treated, which U.S. CBP staffers think is occurring (Harriger). The European Union audit team that visited China also thought they detected instances of fraud. They concluded that “the current system of official controls in China does not adequately ensure that SWPM which forms part of consignments of goods exported to the EU is marked and treated according to ISPM No. 15” (Eyre et al. 2018, p. 713). On the other hand, the US importers in Houston say they are pressing their European suppliers to provide pest-free dunnage.

What more could we ask them to do to ensure that they are not receiving fraudulently marked materials?

Perhaps the problem has a different cause. Are the treatments themselves are less effective than expected? One APHIS study found that twice as many larvae reared from wood treated by methyl bromide fumigation survived to adulthood than larvae reared from heat-treated wood; the reason is unclear (Nadel et al. 2016). Unfortunately, it is apparently impractical to determine whether wood was heat treated by looking for changes in the chemical profile of the wood (Eyre et al. 2018).

Nor can we expect inspection of 100% of all risky consignments or detection of 100% of quarantine pests in those consignments that are inspected. Therefore, the European study authors concluded that inspection is best considered as a means of gathering evidence of risk and a deterrent rather than a means of completely preventing pest movement (Eyre et al. 2018).

The European study authors called for review of ISPM#15 as a control system and to investigate compliance at the source (Eyre et al. 2018 p. 714).

What is APHIS doing?

As I have noted previously – here and here – while U.S. CBP adopted a policy in 2017 under which it can penalize importers for each consignment not in compliance with ISPM#15, APHIS has not followed Custom’s lead on this. Instead, APHIS will apply a penalty only when an importer has accrued five violations over the period of a year. (The two agencies are acting under separate legal authorities.) This is yet another example of APHIS taking a less protective stance – as I described in earlier blogs.

Since Customs is now applying the letter of the law, the most useful step would probably be for APHIS (and the USDA Foreign Agriculture Service) to ramp up efforts to assist U.S. importers which are trying to comply. The importers are begging USDA to provide better information to them about foreign suppliers of wood packaging and dunnage. Which have good vs. poor records? USDA could also help importers trying to complain about specific shipments to the exporting countries’ National Plant Protection Organizations (NPPOs; departments of agriculture).  In addition, APHIS could augment its pressure on foreign NPPOs and the International Plant Protection Convention more generally to ascertain the reasons ISPM#15 is failing and to fix the problems.

APHIS has not been idle. The North American Plant Protection Organization (including Canada and Mexico) has sponsored two workshops intended to educate NPPOs and exporters in Asia and the Americas about the standard’s requirements. APHIS is planning to address wood packaging in an international symposium organized under the auspices of the International Year of Plant Health in July 2020 – I will provide details when they become available.

APHIS is collaborating with the Entomological Society of America to host a workshop on wood packaging at the ESA annual meeting in November 2020 – I will provide details when they become available. The Continental Dialogue on Non-Native Forest Insects and Diseases plans to link its annual 2020 meeting to this workshop.

More immediately, the Continental Dialogue on Non-Native Forest Insects and Diseases will have presentations on the wood packaging issue at its annual meeting in just 11 days! in Cleveland

In preparation for the 2020 meetings, APHIS should fund more studies and audits of wood packaging to document the current efficacy of the standard (that is, the pest approach rate); remember, Haack’s study relied on data which are now a decade old. Not only has time passed … Both the standard and U.S. enforcement policies have changed since 2009.

Significance of the Wood Packaging Problems

The apparent failure of the ISPM#15 standard to provide a reliable means to certify treatment raises obvious issues regarding the risk of pest introductions. However, the implications are much broader.

The premise of the international phytosanitary system – the Agreement on the Application of Sanitary and Phytosanitary Standards (SPS Agreement) and International Plant Protection Convention (IPPC) – is that importing countries should rely on exporting countries to take the actions necessary to meet the importing countries’ plant health goals. The ISPM#15 experience casts doubt on this premise. The exporters are not reliably ensuring the cleanliness of their wood packaging. Worse, wood packaging is easier to treat than fruits, vegetables, and living plants (plants for planting). The latter commodities are much more easily damaged or killed by treatments than are boards or even logs – which are, after all, already dead! (A longer discussion of the SPS Agreement and IPPC is found in Chapter III of Fading Forests II, available here.

I hope that the international phytosanitary community will take advantage of the heightened attention and effort associated with the International Year of Plant Health in 2020 to re-examine all aspects of the current global phytosanitary system.

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.

SOURCES

Eyre, D., R. Macarthur, R.A. Haack, Y. Lu, and H. Krehan. 2018. Variation in Inspection Efficacy by Member States of SWPM Entering EU. Journal of Economic Entomology, 111(2), 2018, 707–715)

Kevin Harriger, US CBP. Presentations to the annual meetings of the Continental Dialogue on Non-Native Forest Insects and Diseases over appropriate years. See, e.g., https://continentalforestdialogue.org/continental-dialogue-meeting-november-2018/

Nadel, N., S. Myers, J. Molongoski, Y. Wu, S. Linafelter, A. Ray S. Krishnankutty, and A. Taylor. 2016. Identificantion of Port Interceptions in Wood Packaging Material: Cumulative Progress Report, April 2012 – August 2016

https://www.joc.com/breakbulk/ispm-15-enforcement-leaves-shippers-no-good-nswers_20190717.htmlhttps://www.joc.com/breakbulk/enhanced-enforcement-ispm-15-costing-us-importers-millions_20190725.html

Recent Developments on Stopping Emerald Ash Borer

post-EAB ash forest in southern Michigan; photo by Nate Siebert, USFS

1) The Risks of Reliance on Biological Control

An article published lately indicates yet another complication that might undercut reliance on biocontrol to counter mortality of eastern ash populations caused by the emerald ash borer (EAB) (See my blogs from November — here and here)  regarding APHIS’ proposal to eliminate EAB quarantines in favor of relying chiefly on biocontrol – with little data to back up the change.)

Olson and Rieske (full citation at the end of this blog) found that one of the principal biocontrol agents now in use, and on which APHIS proposes to rely, Tetrastichus planipennisi, does not parasitize EAB larvae living in white fringetree, Chionanthus virginicus. While this tree is a suboptimal host for EAB – lower numbers of the beetle survive – the white fringetree would support survival of some EAB – thereby undermining efficacy of the biocontrol program.

Since white fringetree grows a cross much of the eastern range of ash trees — from New York to Texas, as shown by the map posted here, the presence of this reservoir that can be exploited by EAB will challenge the efficacy of biocontrol.

Olson and Rieske believe the reason that T. planipennisi does not attack EAB living in white fringetree is that the fringetree’s wood is so dense that the wasp cannot detect the presence of EAB in the tree (T. planipennisi apparently relies on tactile and vibratory clues to find its prey).

2) A Possible New Biopesticide to Suppress EAB?

A presentation at the 81st Northeastern Forest Pest Council by Mark Ardis of C.D.G. Environment described tests in the United States and Canada of methods for killing EAB by contaminating the beetles with the fungus Beauveria bassiana. The company is testing traps in which male beetles enter, become covered by fungal spores, then they fly out. The males not only become ill themselves, they also contaminate females during mating. Average overall beetle mortality from several test sites is 25%.

Given the terrible impact of the EAB invasions, I find it exciting to contemplate development of additional tools to be used in suppressing the beetles. However, I worry about possible impacts on non-target insects which might also be exposed to the fungal spores. A decade ago, David Wagner identified 21 species of insects that were specialists on Fraxinus, and said he expected additional species would also be associated with ash trees (full citation at end of blog). Mr. Ardis assured me that they had detected no insects other than EAB in the traps. I wish to see additional research on this issue.

The  US Environmental Protection Agency would have to approve use of this biopesticide. I suggest that we all keep an eye on this process.

3) Citizen Scientists Searching for EAB- resistant “Lingering Ash”

Jonathan Rosenthal and Radka Wildova of the Ecosystem Research Institute have established a citizen science program to find ash trees that have survived the EAB invasion. These trees will become the foundation of efforts to breed more trees resistant to the EAB, which could be used to restore our forests.

The program is called “MaMa” – Monitoring and Managing Ash. So far, about 30 plots have been set up in New York, New Jersey, and Vermont where citizens are monitoring ash trees that have apparently survived the EAB invasion. The program seeks additional partners from other areas.

Searches for lingering ash must be strategically timed to ensure that the trees identified are truly resistant to EAB – not just late to become infested. But you can’t wait too long after the infestation wave has gone through an area, because the tree might die due to wind throw or human activity. Or, if a tree has just partial resistance (an important attribute for breeding!), it might eventually succumb. It is also imperative to avoid confusing stump sprouts with truly lingering ash. The conclusion: monitor the infestation and search for lingering trees two years after 95% of ash have been killed, or four years after 50% have been killed.

The MaMa program provides guidance, maps, electronic reporting systems … so you can help!

If you wish to participate – or to learn more – contact the program at monitoringAsh.org or 845-419-5229.

SOURCES

Olson, D.G. and L.K. Rieske. 2019. Host range expansion may provide enemy free space for the highly invasive emerald ash borer. Biol Invasions (2019) 21:625–635

Wagner, D.L. Emerald Ash Borer Threatens Ash-feeding Lepidoptera. 2007. News of the Lepidopterists’ Society. Volume 49, No. 1 (Spring 2007)

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.

Spotted Lanternfly – Government Shut-Down Hampered Vital Effort at Crucial Time

spotted lanternfly; photo by Holly Raguza, Penn. Dept. of Agriculture

I last blogged about the spotted lanternfly (Lycorma delicatula) two years ago. At that time, this insect from Asia (where else?) was established in some portions of six counties in southeastern Pennsylvania. While its principal host is tree of heaven (Ailanthus altissima), it was thought to feed on a wide range of plants, especially during the early stages of its development. Apparent hosts included  many of the U.S.’s major canopy and undertory forest trees, e.g., maples, birches, hickories, dogwoods, beech, ash, walnuts, tulip tree, tupelo, sycamore, poplar, oaks, willows, sassafras, basswood, and elms. The principal focus of concern, however, is the economic damage the lanternflies cause to grapes, apples and stone fruits (e.g., peaches, plums, cherries), hops, and other crops.

In the two years since my first blog, the spotted lanternfly has spread – both through apparent natural flight (assisted by wind) and through human transport of the egg masses and possibly adults. By autumn 2018, detections of one or a few adults – alive or dead – had been found in six additional states: Connecticut, Delaware, Maryland, New Jersey, New York, and Virginia.

spotted lanternfly quarantines (blue) & detection locations (yellow)
prepared by Cornell University

How many of these detections signal an outbreak?  It is too early to know.

Impacts of the Government Shutdown

Unfortunately the federal government shutdown forced the cancellation of the annual USDA invasive species research meeting that occurs each January. The spotted lanternfly was to be the focus of six presentations. The most important of these was probably APHIS’ explanation of “where we are and where we are going.” The cancellation eliminated one of the most important opportunities for researchers to exchange information and ideas that could spur important insights. Equally important, the cancellation hampered communication of insights to practitioners trying to improve the pest’s management.

One pressing question was not on the meeting’s agenda, however. Would a much more aggressive and widespread response in 2014, when the lanternfly was first detected, have  eradicated this initial outbreak?  I have long thought that this question should be asked for every new pest program, so that we learn whether a too-cautious approach has doomed us to failure. However, authorities never address the issue – at least not in a public forum.

The shutdown also had an even more alarming impact. It interruptedaid by USDA APHIS and the Forest Service to states that should be actively trying to answer this question. Winter is the appropriate season to search for egg masses.  It is also the season to plan for eradication projects. 

spotted lanternfly egg mass; New York Department of Environmental Conservation

For the first several years, funding of studies of the lanternfly’s lifecycles and host preferences, research on possible biological or chemical treatments, and outreach and education came in the form of competitive grants under the auspices of the Farm Bill Section 10007.  This funding totaled $5.5 million to Pennsylvania.

This commitment pales compared to Asian longhorned beetle or emerald ash borer h— which were also poorly known when they were first detected in the United States.

At the same time, the Pennsylvania infestation spread. It is now known to be established in portions of 13 counties and outbreaks were detected in neighboring Delaware and Virginia. h

This spread – and resulting political pressure – persuaded APHIS to multiply its engagement. A year ago, USDA made available $17.5 million in emergency funds from the Commodity Credit Corporation (that is, the funds are not subject to annual Congressional appropriation). APHIS said it would use the additional funds to expand its efforts to manage the outer perimeter of the infestation while the Pennsylvania Department of Agriculture would focus on the core infested area. APHIS said it would use existing (appropriated) resources to conduct surveys, and control measures if necessary, in Delaware, Maryland, New Jersey, New York and Virginia.

Summary of Latest Status in the Seven States

(see also the write-up here)

Pennsylvania: infestation established (quarantine declared) in portions of thirteen counties (Berks, Bucks, Carbon, Chester, Delaware, Lancaster, Lebanon, Lehigh, Monroe, Montgomery, Northampton, Philadelphia, Schuylkill). The quarantine regulates movement of any living stage of the insect brush, debris, bark, or yard waste; remodeling or construction waste; any tree parts including stumps and firewood; nursery stock; grape vines for decorative or propagative purposes; crated materials; and a range of outdoor household articles including lawn tractors, grills, grill and furniture covers, mobile homes, trucks, and tile or stone. See the regulation here: https://www.agriculture.pa.gov/Plants_Land_Water/PlantIndustry/Entomology/spotted_lanternfly/quarantine/Pages/default.aspx

Delaware: The state had been searching for the insect since the Pennsylvania outbreak was announced. After detection of a single adult female in New Castle County in November 2017, survey efforts and outreach to the public were intensified. Another dead adult spotted lanternfly was found in Dover, Delaware, in October 2018.  

Virginia: infestation established (quarantine declared) in one county. Multiple live adults and egg cases of spotted lanternfly were confirmed in the town of Winchester, Virginia (Frederick County), in January 2018.   As noted in my earlier blog, this region is important for apple and other orchard crops and near Virginia’s increasingly important wine region.

New Jersey: The New Jersey Department of Agriculture began surveying for lanternflies along the New Jersey-Pennsylvania border (the Delaware River) once the infestation was known. It found no lanternflies before 2018. In the summer, however, live nymphs were detected in two counties, Warren and Mercer. In response, the state quarantined both those counties and one located between them, Hunterdon. The state planned to continue surveillance in the immediate areas where the species has been found as well as along the Delaware River border in New Jersey.  

New York: In 2017, a dead adult lanternfly was found in Delaware County. 

State authorities expressed concern about possible transport of lanternflies from the Pennsylvania infested area.

In Autumn 2018, New York authorities confirmed several detections, including a single adult in Albany and a second single adult in Yates County. In response, the departments of Environmental Conservation and Agriculture and Marketing began extensive surveys throughout the area. Initially they found no additional lanternflies.

However, a live adult was later detected in Suffolk County (on Long Island).

Connecticut:  a single dead adult was found lying on a driveway at a private residence in Farmington, CT, in October 2018. The homeowner was a state government employee educated about the insect. Relatives had recently visited from Pennsylvania (Victoria Smith, Connecticut Agricultural Experiment Station, pers. comm.). Searches found no other spotted lanternflies on the property. The state plans additional surveys in the area to confirm that no other spotted lanternflies are present.  

Maryland: A single adult spotted lanternfly (male) was caught in a survey trap in the northeast corner of Cecil County near the border of Pennsylvania and Delaware (an area of known infestation) in October 2018. Because of the lateness of the season and sex of the insect, the Maryland Department of Agriculture does not believe that the lanternfly has established there.

All the affected states are encouraging citizens to report any suspicious finds.

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.

New Study of Why People Move Firewood – and Its Relation to EAB Deregulation

We know that people moving firewood long distances is cause for great concern because of the likelihood that tree-killing pests will be transported to new and previously uninfested locations. This concern has been heightened by the USDA APHIS proposal to deregulate the emerald ash borer (EAB). As the principal federal “quarantine pest” transported by firewood, the EAB provides the legal foundation for most federal and state firewood regulations. (Of course, the EAB regulations also govern other articles that could transport wood-boring pests). (See earlier blogs here and here.)

Most forest pest professionals agree that the greatest risks are associated with individuals who transport firewood for recreational camping or summer homes. These people have proven to be the most difficult to regulate and the most likely to not see – or to ignore – messages intended to discourage them from moving firewood. The Nature Conservancy manages the “Don’t Move Firewood” program. It has done polling on messages and impact and concludes that the percentage of U.S. voters who have heard a “don’t move firewood” message remains steady and that those who have heard that message are less likely to transport firewood, especially over distances greater than 50 miles. More details are here

A recently published study by several academics and one forest service scientist reinforces The Conservancy’s earlier conclusion about the importance of outreach efforts as an essential component of programs intended to manage wood-boring pests. On the other hand, the new study points to additional nuances in crafting messages that will be effective in changing people’s behavior.

 

Findings

 

Daigle et al. 2018 (see full citation at the end of the blog) surveyed 272 people who were camping in public (state) or private campgrounds in three New England states in 2013 – four years after each of those states adopted regulations prohibiting out-of-state firewood and began their outreach efforts. Some campers apparently feel a strong connection to the place they are visiting, as shown by the fact that 84% of the 79 campers at private campgrounds had spent two or more nights camping in the same state in the previous year. That emotional connection might provide a motivation that could be activated to persuade those campers to stop transporting firewood (see below).

The authors found that slightly more than 25% of the 272 respondents reported that they often or always brought firewood from home for camping. More discouraging is that they found that people might not comply even when informed about the risks. Instead, compliance depended largely on the individual’s motivation and commitment level rather than knowledge. Worse yet, campers categorized as “highly involved” in the forest pest issue were just as likely to transport firewood from home as were others. Apparently, these non-compliant campers did not fully “connect the dots” between their concerns about forest health and their own actions. See below for Daigle et al.’s suggestions for ways to help people make those connections.

To understand the role of motivation, Daigle et al. tried to assess the strength of each camper’s beliefs about the relationship between tree-killing pests and the transport of firewood by recreational campers.

Overall, 25% of respondents were very highly involved with tree pest issues; another 22% were highly involved. Respondents’ perception of the relationship between damaging tree pests and transport of firewood differed significantly based on their levels of involvement. Respondents with a low level of involvement were less likely to agree with three statements (listed below) that firewood-associated pests pose a serious threat. Campers with very high levels of involvement strongly disagreed with three other statements that either downplayed the threat or portrayed the respondent’s compliance as “useless” as long as others continue to transport firewood.

Perception questions against which respondents’ agreement or disagreement was measured:

  • “There is not much one individual can do about invasive pests brought in by firewood”
  • “I don’t think invasive pests brought in by firewood are very important.”
  • “The threat of invasive pests brought in by firewood is serious.”
  • “As long as other people continue to bring firewood from home, my efforts to prevent invasive pests are useless.”
  • “The invasive forest pest risk from firewood is exaggerated.”
  • “In the long run, things will balance out with invasive pests.”

 

Rationale

Respondents’ most frequent explanations for why they take firewood from home when they go camping were cost, quality, and convenience. The most frequently cited reason for not transporting firewood was that the respondent knew that it was not allowed.

Level of pest awareness:

While nearly all respondents (92%) had heard something about non-native pests killing trees, but 57% could not recall the name of a specific pest in the absence of a prompt. When asked about the emerald ash borer and Asian longhorned beetle, more respondents had heard about the ALB (77% v. 52%). Most said the principal source of information was a state agency.

 

Suggested Actions

Daigle et al. conclude that authorities need to increase citizens’ exposure to outreach materials in order to activate concern and bring about desired actions to curtail risk of pests in firewood.

One clear need is to counter many campers’ belief that their wood is safe so it is okay to transport it regardless of the regulations. Often they based that belief on the fact that their home is not in a designated quarantine zone. Daigle et al. suggested that educational material should try to counter this belief by emphasizing the time lag between a pest’s establishment and its detection.

To help “connect the dots” between campers’ concerns about forest health and the implications of their actions (transporting firewood), survey respondents suggested using more visuals showing the destruction caused by the invasive forest pests, especially in areas they care about – close to home or favorite recreation areas. Daigle et al. thought such pictures would “help the campers with high involvement to trigger activation of attitudes with the association of forest pests and firewood transport.”

Other suggestions for strengthening outreach were to ensure that the message

  • Is novel – that it does not simply reiterate a camper’s initial belief system.
  • Produces agreement by the recipient without generating counterarguments.
  • Is relevant to the audience’s concerns.

They also suggested that campgrounds (public and private) help motivate campers to leave firewood at home by coordinating with local firewood vendors to provide competitively priced firewood at the campground or by including the cost of providing some firewood in the camping fee.

Daigle et al. made two other suggestions that call for stronger actions.

First, they suggested that outreach programs incorporate incentives or rewards to engage people who don’t have a high level of involvement in forest health issues.

Second, they suggested that authorities reinforce the educational message by using “more direct” actions, such as

  • confiscating illegally transported firewood at check stations,
  • issuing warnings about such actions, or
  • administering fines for moving non-compliant firewood.

The authors suggest that state agencies should consider taking these actions – but I see no reason why federal agencies should not also.

EAB; David Cappaert

Conclusions re APHIS’ Proposal to Deregulate EAB

Daigle et al. conclude that outreach efforts aimed at curtailing movement of firewood need to be continued. They are a critical component of overall management programs targetting non-native tree-killing pests – programs developed through decades of research and trials. The motive is clear: more effectively delaying these pests’ spread provides large benefits to municipalities and homeowners.

These are the same points made by many who opposed APHIS’ proposal to deregulate the emerald ash borer.

In its comments to APHIS, The Nature Conservancy noted that the domestic EAB quarantine had been effective in limiting spread of the pest through two of the most important pathways – firewood and nursery stock. The resulting slower spread had protected three-quarters of the ash range in the United States and bought time to develop mitigation measures.

Further, eliminating the federal quarantine would not only unleash this pathway for long-range movement of EAB but undermine the many federal, state, regional, tribal, private, and non-profit  partners’ efforts to curtail movement of all invasive forest pests in firewood.

Many other commenters, including several state agencies, the National Association of State Foresters and Southern Group of State Foresters called for APHIS to continue leading national efforts to curtail spread of EAB and other pests through careless movement of infested firewood. The Montana Department of Natural Resources and Conservation and NASF specifically urged that APHIS reinstate the National Firewood Task Force (which APHIS led in 2009-2010).

The Don’t Move Firewood program has a more informal blog on this topic, available here.

 

Source

Daigle, J.J., C.L. Straub, J.E. Leahy, S.M.De Urioste-Stone, D.J. Ranco, N.W. Siegert. How Campers’ Beliefs about Forest Pests Affect Firewood Transport Behavior An Application of Involvement Theory. Forest Science XX(XX):1-10  https://academic.oup.com/forestscience/advance-article/doi/10.1093/forsci/fxy056/5232804

 

APHIS’ Strategic Plan – Focus on Deregulation & Trade Facilitation

APHIS’ headquarters building

USDA APHIS released its Strategic Plan for fiscal years 2019-2023 just after Thanksgiving. The report is 21 pages long. There is no evidence that any stakeholders were asked for input or review.

The Plan has a disappointing – but not surprising – emphasis on deregulation and “customer service”. A second – and more surprising weakness is the lack of attention to plant pests – even those of agriculture, much less natural resources. The emphasis is clearly on animal pests and diseases – including zoonotics.

APHIS’ mission is “To safeguard the health, welfare and value of American agricultural and natural resources.” To accomplish this mission, APHIS has set three goals:

  • Deliver efficient, effective, and responsive programs.
  • Safeguard American agriculture.
  • Facilitate safe U.S. agricultural exports.

Most references to protecting natural resources relate to finding more environmentally sensitive approaches for the program under which APHIS reduces human-wildlife conflicts (e.g., birds being struck by airplanes).

In the Plan, APHIS Administer Kevin Shea writes in his opening message that achieving APHIS’ difficult mission of protecting the health and value of America’s agriculture and natural resources cannot be accomplished by APHIS alone. Instead, the agency must work collaboratively with other government agencies and industry, and consult regularly with partners and stakeholders regarding programs’ effectiveness. Administer Shea also highlights the importance of “delivering our programs and services efficiently, effectively, with integrity, …” The agency promises to modernize information technology, data management, methods of communication with collaborators, exporters and importers, etc., in order to give good return on expenditure of taxpayer resources. APHIS also pledges to make decisions based on science. There are seven references to basing decisions on scientific data.

Fair enough. Such emphases were to be expected from Trump Administration and prefigured by USDA Secretary Sonny Perdue during his nomination hearing, e.g., facilitating exports, supporting better information technology.

However, the Plan refers to “customer service” or “customer experience” 34 times. An additional seven references are made to reducing regulatory burdens. The Plan also speaks of the need to “protect the health, welfare, and value of American agriculture and natural resources. … at a reasonable cost. … Easing regulatory burdens makes it easier to create jobs and promote economic growth.” (Emphasis added.)

Perhaps the recent proposal to deregulate the emerald ash borer is driven in part by the emphasis on minimizing costs to regulated industries and seeking alternative approaches? (Although the deregulation has been under discussion for several years, predating the Trump Administration.)

from APHIS PPQ website

The imbalance in attention to animal versus plant pests and disease is striking. Each of the 14 goals is supported by a number of specific tactics. There are a total of 100 “tactics” under the two goals most directly relevant to preventing or managing pest introductions. These goals are: “Protecting America’s agriculture” and “Promoting U.S. agricultural exports.” Of the 100 tactics, only ten are clearly related to plant pests; 19 are pretty clearly activities that apply to both plant and animal pests and diseases; and five are unclear as to whether they include plant pests as well as animal diseases. Thus, only a third of the tactics apply!

[In making this calculation, I did not include 43 tactics listed under the first goal (“Deliver efficient, effective, and responsive programs”) or three objectives under the goal of “Protecting American agriculture” that apply explicitly to wildlife management, regulating genetically engineered organisms, or ensuring humane treatment of animals.]

Specific examples of such lack of balance include the six examples illustrating the declaration (on p. 4) that “Pest and disease events are more frequent, more complex, and less predictable.” Five of the examples are animal diseases, the sixth is the insect-vectored human disease caused by the Zika virus.

In discussing its efforts to balance its safeguarding efforts against increasing requests for market access by international trading partners, APHIS mentions some activities pertinent to plant as well as animal pest management, e.g., examining disease and pest risks and inserting mitigation strategies into international agreements and interstate movement protocols. However, the only specific action it mentions is helping countries to build capacity to implement the Global Health Security Agenda.

The only reference to forest pests is under one of the 24 tactics associated with Goal 2. Safeguard American agriculture, Objective 2.1: Prevent damaging plant and animal pests and diseases from entering and spreading in the United States to promote plant and animal health. This tactic calls for strengthening the North American perimeter against pest threats from outside the region to prevent introduction of agricultural, forest, and other invasive pests.

Why are Plant Pests slighted?

Perhaps plant-related efforts were left out because they are less “sexy”? Or because they are more distantly linked to human health? The Plan does state that “The tactics in this plan represent only a portion of APHIS activities and by no means embody all the important work APHIS does to fulfill its mission.”

Who knows what was left out?

How will adoption of this strategy affect future efforts to address tree-killing insects and pathogens – both those already present in the country and those yet to be introduced?

Might PPQ Fill in the Gaps?

In 2014 APHIS Plant Protection and Quarantine issued its own strategic plan. This supplementary plan made frequent mentions of safeguarding natural resources. Indeed, the third of the plan’s seven goals stated:                              

Goal 3: Protect forests, urban landscapes, rangelands and other natural resources, as well as private working lands from harmful pests and diseases

Several “tactics” under each goal also directly applied to protecting natural resources. I list them below:

1) Prevent the entry and spread of ag pests and diseases.

  • Coordinate with Canada to implement an effective multi-national system that reduces the threat of tree pests arriving from Asia and other parts of the world (e.g. AGM).

3: Protect forests, urban landscapes, rangelands and other natural resources, as well as private working lands from harmful pests and diseases

  • Maintain EAB regulatory framework to focus on the leading edge of infestations while minimizing impacts on regulated businesses in quarantined areas.
  • Evaluate the effectiveness of biocontrol releases in states and combining both regulatory & outreach activities to address the risks of moving logs, firewood, and nursery stock.
  • Examine detection technologies and partnering with states to determine and apply the most effective strategies to survey & eradicate the Asian longhorned beetle
  • Partnering with federal and state agencies to enact measures such as a public outreach campaign to mitigate the movement of forest pests through firewood.
  1. Ensure the safe trade of ag products, creating export opportunities for U.S. producers
  • play a leadership role in revising ISPM#15
  1. Protect the health of U.S. agricultural resources, including addressing zoonotic disease issues and incidences, by implementing surveillance, preparedness and response, and control programs
  • Strengthen partnerships with Tribal Nations to develop a robust surveillance and early detection system for detecting and reporting invasive species.
  • Work with all stakeholders to coordinate all-hazards agriculture and natural resources response support.
  • Develop science-based programs in collaboration with industry and academia to jointly identify practices that will mitigate pest damage. E.G., SANC program http://sanc.nationalplantboard.org/ [a Systems Approach to Nursery Certification] implemented jointly with the National Plant Board and nursery industry

Dare we hope that PPQ adopts an updated strategic plan that fills in some of the gaps in the overall APHIS plan?

 

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.

 

Comments on EAB deregulation show costs would be too high

Kelly Church (Grand Traverse Band Ottawa Chippewa) with baskets she wove from black ash

 

As you know, in September APHIS published a proposal to alter management of the emerald ash borer (EAB). Under the proposal, APHIS would no longer regulate movement of firewood, nursery stock, or other items that can transport EAB to new areas. Instead, APHIS proposed to rely on biological control to reduce impacts and – possibly – slow EAB’s spread. I have posted two blogs about the weaknesses of the underlying analysis and the decision by the Center for Invasive Species Prevention to oppose the proposal. The proposal, accompanying “regulatory flexibility analysis,” and 150 comments by the public are posted here.

The Don’t Move Firewood program has provided links to the individual organizations’ comments here.

 

Here I summarize major points made by those commenting on the proposal.

Most state agriculture departments accepted the proposal. Few commented at all, leaving that to the National Plant Board. The NPB letter consisted of only four paragraphs. In contrast, several state forestry agencies commented.

Several organizations, including the National Plant Board and AmericanHort, agreed with APHIS that the quarantine has not worked primarily because detection tools are so poor. As a result, EAB is able to firmly establish for several years and spread in a new area before authorities detect it and take action.

It is clear from the comments that deregulating EAB might save APHIS money and effort, but the action will exacerbate the already substantial burden on many other U.S. entities – ranging from federal agencies such as USDA Forest Service and National Park Service to homeowners; woodlot owners to (potentially) exporters of all sorts of products; to Native Americans. The economic components of this potential burden surely deserve more serious evaluation as required under several Executive orders.

Comments Categorized

1) The quarantine has slowed the spread of EAB and it remains valuable in granting communities time to prepare

Several of the commenters wished to counter the proposal’s inference that quarantines had failed; rather, they insisted that quarantine has slowed spread of the EAB and that this strategy is still valuable because it gives un-infested areas more time to prepare. Those voicing this view included the National Association of State Foresters; Maine Department of Agriculture, Conservation and Forestry; Montana Department of Natural Resources and Conservation; Fond du Lac Band of Lake Superior Chippewa in Wisconsin; several bands of Native Americans in Maine (Houlton Band, Penobscot, an individual member of the Penobscot); The Nature Conservancy; a man who is both park superintendent for the City of Kalispell, Montana and Chair of the Montana Urban and Community Forestry Association; three local conservancies in Oregon (West Multnomah Soil and Water Conservation District;  Four-County Cooperative Weed Management Area from Clackamas, Clark, Multnomah and Washington counties in the greater Portland Metro area; Tualatin Soil and Water Conservation District); Jefferson County Colorado Invasive Species Management team; Maine Mountain Collaborative; Blue Hill Heritage Trust of Maine; a small woodland owner in Maine; and a Professor in the School of Forest Resources at the University of Maine.

Oregon’s Department of Environmental Quality Water Quality Division opposed the APHIS proposal. The Division noted that EAB spread in the east was facilitated greatly by the continuity of ash habitats whereas ash habitats are much more patchy in the West. Given this situation, human transport is the most likely means by which EAB will reach the West – either from infested portions of the U.S. or via trans-Pacific trade.

A few entities that supported APHIS’ proposal – e.g., the Southern Group of State Foresters and – in a separate letter – Texas Forest Service – also said the quarantine had been helpful.

As The Nature Conservancy said in its comments, the quarantine effectively limits two of the most important pathways, firewood and nursery stock. The result has been to protect much of the country from the pest and buying time to develop mitigation measures.

 

2) APHIS’ dismissal of quarantine is a worrying message (see also discussion of firewood below)

Several of the commenters expressed concern that APHIS too curtly dismissed the value of quarantine – both as it functioned to slow spread of EAB and as a tool used against a wide range of pests. Commenters raising issues about the proposal’s apparent undermining of quarantine as a strategy included the Kansas Forest Service; Maine Department of Agriculture, Conservation and Forestry; Vermont Agency of Agriculture, Food and Markets and the Department of Forests, Parks, and Recreation; and Wisconsin Department of Natural Resources Division of Forestry. The Vermont and Wisconsin agencies asked APHIS to clarify to affected parties what it expects to achieve by the proposed deregulation. The Fond du Lac Band of Chippewa warned that the public might interpret the dropping of regulations as signaling that EAB is no longer important.

Five organizations unified under the banner of the Coalition Against Forest Pests noted that APHIS had set a precedent of dropping regulations when quarantines appear to fail.

A subset of these comments focused on a lack of clarity by APHIS as to its future strategy.

Several commenters said that APHIS had not outlined a coherent strategy for the future. The Kansas Forest Service even called the proposal an agency “exit strategy” rather than a coherent plan. Others raising this issue included the Maine Department of Agriculture, Conservation and Forestry; South Dakota Department of Agriculture and Department of Game, Fish and Parks; and the Coalition Against Forest Pests. Maine noted that the proposal would shift the burden of regulation to the states. Maine and South Dakota said that APHIS, as the responsible federal regulatory agency, should provide a clear and consistent process for regulation of potentially infested products across state lines.

The Tennessee Forest Health Coordinator called for an analysis of EAB program successes that might point to ways in which APHIS could support alternative strategies. A professor of forestry in Maine said APHIS should evaluate and assess techniques specifically to optimize the effectiveness of education and outreach.

Among entities which supported APHIS’ proposed new approach, the Southern Group of State Foresters, Texas Forest Service, and two Vermont agencies – Agency of Agriculture, Food and Markets and the Department of Forests, Parks, and Recreation – urged APHIS to champion a national, multi-agency approach to managing EAB, including creation of a national, voluntary treatment standard and label for firewood; redirecting all savings to research & management – including state surveys. These groups also advocated funding increases for APHIS, the USDA Forest Service, and state EAB programs; and support for states to carry out their enlarged responsibilities for survey, outreach, education, and assistance to affected parties.

The Vermont agencies wrote that EAB “is a nationally significant pest, … which warrants a significant federal role.” Because EAB impacts on communities, forest health, and the forest economy continue to expand, a decision to discontinue regulatory activities should be accompanied by increased federal support for research and management.

The National Association of State Foresters also called for APHIS to champion a national, multi-agency approach, with a somewhat longer list of components. These should include support state research and management efforts, the biocontrol program, identifying genetic strains of ash trees that are resistant to EAB, maintain national treatment criteria for wood products (including firewood), and reconvene the National Firewood Task Force. NASF also urged the USDA Forest Service to develop a cooperative management program to sustain and replace ash trees killed by EAB.

Dr. David Orwig of Harvard Forest also called for funding not just biocontrol but also research areas like silviculture, chemical control, ash utilization, and management guidelines.

This pattern of asking for continued or expanded federal engagement – beyond biocontrol – is quite apparent.  Some entitites that said they supported APHIS’ proposal nevertheless called for the agency to continue detection and response components of the program – expressly contrary to the proposal itself.

Thus, AmericanHort, the two Vermont agencies, Wisconsin Department of Natural Resources Division of Forestry, and two Maine departments called for APHIS to continue or increase its engagement in EAB detection and other management activities – including biocontrol, outreach to explain the change in strategy, and engaging the National Park Service and Forest Service in promulgating a consistent firewood policy.

Others who asked for similar commitments were straightforward in opposing the proposal. Thus the North Dakota Department of Agriculture and North Dakota Forest Service – in separate letters – asked that APHIS continue to provide resources to help states monitor EAB presence and respond to any new detections. The Oregon Department of Forestry asked that federal agencies continue to fund research and development of early detection and rapid response strategies for EAB; conservation of ash genetic resources and promotion of natural resistance; research on uses of dead ash; as well as classical biocontrol once EAB is established in a new area.

Several commenters said that they had considered APHIS to be a critically important partner in countering the EAB and were disappointed that the agency is backing away. Native Americans in particular considered the proposal to be a betrayal of the Federal government’s treaty responsibilities vis a vis recognized tribes. The Fond du Lac Band of Wisconsin wrote that upholding a federal EAB regulation is vital to the protections of important cultural and natural resources both on the Reservation and within territories ceded to the Band by several 19th Century treaties. The tribe cited EO 13175 issued by President Clinton. The Houlton Band of Maine said APHIS has a mission to defend federally recognized tribes against invasive species.  The federal government should not make a decision so contrary to its fiduciary trust responsibility to federally recognized tribes.

 

3) Need for continued APHIS leadership on firewood regulation

The importance of APHIS continuing to lead national efforts to curtail spread of EAB (and other pests) through careless movement of infested firewood was stressed by many commenters. Voicing this need were many of the entities which opposed the proposal, including Maine Department of Agriculture, Conservation and Forestry; Montana Department of Natural Resources and Conservation; Southern Group of State Foresters; Texas Forest Service; the two Vermont agencies; The Nature Conservancy; and the National Association of State Foresters. As noted above, the NASF, Southern Group, Texas, and Vermont all said APHIS should support creation of a national, voluntary treatment standard & label for firewood. TNC said eliminating the EAB quarantine – the best known and understood firewood regulation – will exacerbate difficulties of outreach. Public outreach and education work best when they are backed up by core consistent rules. Montana Department of Natural Resources and Conservation and NASF called for reinstating the National Firewood Task Force (which APHIS led in 2009-2010).

Several entities that supported the proposal also called for continued APHIS engagement on firewood. One, the Wisconsin DNR Division of Forestry, urged APHIS to work with the National Park Service and Forest Service to create a consistent firewood policy. A second, the NPB, noted that it is developing guidance to states interested in initiating regulations, best management practices, or outreach programs. The NBP added that it welcomes any assistance from APHIS.

As The Nature Conservancy and Tennessee Forest Health Coordinator pointed out, the firewood effort – federal regulations, state regulations, education and outreach under the “Don’t Move Firewood” campaign – all helped curb movement of several tree-killing pests, not just EAB.

 

4) Others Pointed Out the Importance of Consistent Regulations to Keep Markets Open

A smaller number of entities addressed the similar importance of consistent rules governing interstate and US-Canadian trade in other types of vectors that can transport EAB and which are to be deregulated under the proposal. These included the NASF.  Several private groups from Maine and the Maine Department of Agriculture, Conservation and Forestry noted the importance of reaching agreement with Canada, which is a major market for their wood products. The two South Dakota departments also expressed concerns.

The National Wooden Pallet and Container Association raised the prospect of truly tremendous disruption of trade. At present, the United States and Canada exempt wood packaging originating in either country from requirements that it be treated in accordance with international standards (ISPM No. 15). Canada has many reasons to fear that crates and pallets carrying exports from the U.S. might be infested by EAB once APHIS stops enforcing quarantine regulations. If Canada responds by ending the exemption and requiring wood packaging from the U.S. to comply with ISPM#15, that action would affect a wide range of U.S. exports – from fruits to auto parts. In 2017, the U.S. exported $282 billion worth of goods to Canada (Office of the U.S. Trade Representative)

 

5) The Economic Analysis Underlying the Proposal was Inadequate

Several commenters criticized the adequacy of the economic analysis. The most specific criticisms were put forward by the California Forest Pest Council; CISP; the five organizations commenting under the banner of the Coalition Against Forest Pests; and the National Wooden Pallet and Container Association. The latter two cited specific Executive orders and the Paperwork Reduction Act in calling for a review of the proposal by the Office of Management and Budget & USDA Office of General Counsel to reassess whether it meets the conditions for the reduced economic analysis. As noted above, the NWPCA mentioned specifically a fear that Canada might discontinue the mutual exemption under which wood packaging may move between the two countries without being treated in accordance with ISPM#15. The possibility of such an action would certainly push the proposal over the $100 million threshold for completing much more rigorous economic analyses.

Other economic concerns not adequately addressed in the view of the commenters relate to costs arising earlier due to the faster spread of EAB to un-infested western states. Costs imposed earlier than would otherwise be the case are considered relevant in regulatory decisions. Furthermore, businesses in these and possibly other states will face new regulations adopted by states to fill the void left by federal deregulation. Finally, the lack of consistency arising from separate state regulations will impede interstate or US-Canada commerce.

Non-regulatory costs – death of trees and associated removal costs – costs to the forest industry, plus municipalities and home owners in areas not currently affected by infestation – were also not discussed in the proposal.

Several commenters said that APHIS had underestimated the ecological and cultural values threatened by spread of EAB. These included the Fond du Lac Band, Penobscot band, TNC, the Oregon soil conservation district and weed management area; Maine Mountain Collaborative and Woodland Owners, as well as several individuals.

The Nature Conservancy noted that three-quarters of the native ash range of the conterminous United States and 14 of vulnerable species in the U.S. and Mexico are still free of EAB as a result of the quarantine.

A Minnesota community’s Parks Commission noted that loss of trees to EAB can lead to other problems and costs. Consequently, the goal of “saving money” will not be achieved. In short, EAB-caused tree mortality “affects communities, including residents, homeowners, and taxpayers. Funding should be directed both to slowing the spread of the pest and to treatment of affected trees.”

A small woodland owner in Maine asked why APHIS did not evaluate economic impacts to landowners & municipalities.

Oregon’s Department of Environmental Quality Water Quality Division added that pesticides used to control EAB might cause negative impacts in riparian and aquatic environments.

 

6) Several Commenters questioned whether freed-up funds would support biocontrol – or whether they should

As noted in my earlier blogs, there are questions about whether biocontrol will be efficacious in protecting forests across the continent. CAFP echoed these questions. Blue Hill Heritage Trust of Maine called biocontrol experimental.

The Fond du Lac Band pointed out that most tribes don’t accept biocontrol on their reservations – so spending all available funds on this approach doesn’t help Native Americans.

The Maine government and the Penobscot Band of Maine expressed doubt that increased funding would actually materialize.

 

7) Comments that do not fit neatly into these categories.

The California Department of Agriculture said that it intends to promulgate a state exterior quarantine to protect its agriculture (olive trees are hosts of EAB) and environment.

The South Dakota Department of Agriculture and Department of Game, Fish and Parks concluded that interstate regulatory options should be a higher priority than other methods of control.

The Houlton Band of Maine said that maintaining the domestic quarantine is the only federal action that can adequately address the universally agreed fact that human activities cause the rapid spread of EAB.

The Western Governors Association described the region’s vulnerability to EAB spread and, citing recent Association policy resolutions, said a decision of this magnitude should be made only after substantive consultation with Western Governors.

The National Association of State Foresters pointed out that a decline in federal funding for EAB detection surveys will significantly reduce state forestry agencies’ capacity to monitor and respond to EAB spread.

The Jefferson County, Colorado Invasive Species Management team recommended retaining the quarantine using either the 100th Meridian or Continental Divide as the containment boundary. It cited as a justifications the “culture of vigilance” created by strong quarantines. This vigilance saves financial resources and protects natural and agricultural resources.

Finally, the Fond du Lac Band of Lake Superior Chippewa said that abandoning methods that are in place for the prevention of EAB’s spread, such as federal and state quarantines, and favoring only options that focus on rehabilitating a site after it has undergone a severe infestation, presents a large and unnecessary ecological risk. Invasive species programs have always focused on “prevention” being the key.

 

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.

Report Lists Non-Native Species in the U.S.

Ailanthus altissima

Several scientists at the United States Geological Service (USGS) have published a report and accompanying datasets that attempts to provide a publicly accessible and comprehensive list of non-native species established in United States.

Led by Annie Simpson and Meghan C. Eyler, a team of six scientists worked six years (2013–2018). They reviewed 1,166 authoritative sources to develop a list of 11,344 unique names – most of them binomials (genus and species), a few genera, plus some viruses.

This was a Herculean effort that produced very valuable products. We are all in their dept!

Simpson and Eyler point out that knowing which species are non-native to a region is a first step to managing invasive species. Lists compiled in the past were developed to serve a variety of purposes, including watch lists for preventing invasions, inventory and monitoring lists for research and modeling, regulatory lists for species control, and non-regulatory lists for raising awareness. As a result, they are not comprehensive.

Among the sources these authors consulted in preparing the list were peer-reviewed journal articles, books, brochures, circulars, databases, environmental assessments, technical reports, graduate theses, and websites.

Data – by Region

The report also notes which non-native species were established in each of three regions: the “lower 48” states, Alaska, and Hawai`i. Not surprisingly, more than half the non-native taxa are established in the vast area (nearly 7.9 million km2) comprising the “lower 48” states – 6,675 taxa. Almost half of the total number of non-native taxa have established in the tiny geographic region (only 28,311 km2) of Hawai`i – 5,848 taxa.  One-tenth as many non-native taxa – 598 – are reported as established in Alaska (1.7 million km2).

This report includes taxa that are not native to any part of the specific region, but established (naturalized) somewhere in the region. An “established” species must have at least one population that is  successfully reproducing or breeding in natural systems. The list includes domesticated animals and plants introduced for crops or horticulture when the taxon has escaped cultivation or captivity and become established in the wild. Species listed range from feral hogs (Sus scrofa) to plum pox virus and citrus canker to ohia rust (Puccinia psidii).

Of the total 11,344 taxa, 157 are established in all three regions. These included 125 vascular plants (especially grasses and asters); 13 arthropods, 11 mammals; 6 birds; 3 mollusks; 1 bryozoan. One of the ubiquitous plant species is tree of heaven (Ailanthus altissima). I find it entirely appropriate that the cover photo shows this tree – the photo was taken 8 miles from my home in Fairfax County, Virginia.

Nearly three-quarters (71.4%) of the non-native species in Alaska are plant species. More than half (59.7%) of the non-native species in the “lower 48” region are also plants. Nearly all the remainder of the non-native species in both regions are some kind of animal. Fungi constitute only 1.8% of the non-native species in the “lower 48” region; all the rest of the groups (Bacteria, Chromista, Protozoa, Virus) constitute less than 1% of the non-native species recorded in either region.

By contrast, in Hawai`i, animals make up 69.7% of the listed non-native species; most are invertebrates. Plants constitute 29.8% of the Hawaiian list.

Gaps, by Taxon

The authors recognize that invertebrates and microbes are under-represented because species are still being discovered; non-charismatic and difficult-to-identify species tend to be overlooked; and the species composition of any nation in this era of globalization is constantly subject to change.

I have noted some gaps among the pathogens: the absence of some of the Phytophthora that have been detected infecting shrubs and herbaceous plants in California,  e.g., Phytophthora cambivora, siskiyouensis, tentaculata;  and the “rapid ohia death” pathogens, Ceratocystis huliohia and C. lukuohia. Dr. Simpson is aware of these gaps and is soliciting sources to help add these organisms – especially the various Phytophthora species – to the next version of the list.

Simpson and Eyler note that the relative geographic distribution of the list at its current state seems to reinforce three well established premises: that tropical island systems are particularly vulnerable; that higher latitudes host fewer but are not invulnerable; and that species diversity in general decreases with increasing latitude.

 Comparisons to Other Databases

After standardizing the names in the list by comparing them to the Integrated Taxonomic Information System (ITIS), Simpson and Eyler also reviewed the USGS BISON database, which has more than 381 million occurrence records for native and non-native species in the U.S. and Canada, covering 427,123 different taxa. (The BISON database contains significantly more species occurrences for the U.S. than the largest invasive species database, EDDMapS, which contained 4.4 million species occurrences as of June 2018.) Simpson and Eyler had to evaluate which of these taxa met their definition of non-native, since most species occurrence records in the USGS BISON are not labeled as non-native in the original records.

Comparing the BISON and non-native lists, Simpson and Eyler found that the BISON list contained a larger number of occurrence records for non-native taxa: a total of 13,450,515.However, the BISON list does not provide complete coverage of non-native species: it includes records for 77% of list of non-native species Simpson and Eyler found in Alaska, 75% of the “lower 48” sublist, but only 37% of the Hawaiian sublist.

Simpson and Eyler state their intention to continue updating the list of non-native species, they welcome contributions to it from area experts, and they urge integration of new occurrence data into invasive species database such as EDDMapS.

Indicators of Non-Native Species Richness

Figure 3 in the report (above) maps the number of non-native taxa in BISON at the county level. Figure 4 displays the proportion of non-native to native species in BISON. Higher percentages are generally evident in coastal areas and other regional hotspots. For example, the proportion in Hawaiian counties is greater than 33%. Additional data are needed to perform a more in-depth analysis of non-native species richness and abundance.

UPDATE! New Report in the Works

In June 2021, USGS announced that it was updating its Comprehensive List of Non-Native Species Established in 3 Major Regions of the U.S. so that the document more closely aligns with the parameters of the Global Register of Introduced and Invasive Species. The new USGS dataset is to be called the US Register of Introduced and Invasive Species. The list in the current draft includes 15,364 records. About 500 of these records are in Alaska, 6,000 in Hawai`i, and 8,700 in the conterminous 48 States.

One of the lead authors, Annie Simpson, contacted invasive species experts seeking feedback and suggested additions – based on authoritative resources such as peer reviewed journal articles, pest alerts, databases, books, and technical bulletins. She sought input by 25 July, 2021.

The published version of this dataset will be made freely available on USGS’ ScienceBase (https://www.sciencebase.gov), and all reviewers will be acknowledged in the dataset’s abstract.

SOURCE

Simpson, A., and Eyler, M.C., 2018, First comprehensive list of non-native species established in three major regions of the United States: U.S. Geological Survey Open-File Report 2018-1156, 15 p.

The report and accompanying data tables are available here.

South African report

In an unrelated but similar development, South Africa has issued a report on its invasive species — 2017 The Status of Biological Invasions and Their Management in South Africa. The report analyzes pathways of introduction and spread; number, distribution and impact of individual species; species richness and abundance of alien species in defined areas; and the effectiveness of interventions. The report notes that 775 invasive species have been identified to date, of which 556 are listed under some national regulatory program. Terrestrial and freshwater plants number 574 species; terrestrial invertebrates number 107 species. (This total does not include the polyphagous shot hole borer, which was detected too recently.) 107 species are considered by experts to be having either major or severe impacts on biodiversity and/or human wellbeing. Alien species richness is highest in the savanna, grassland, Indian Ocean coastal belt and fynbos biomes, lower in the more arid Karoo and desert biomes. South Africans are particularly focused on the reductions in surface water resulting from plant invasions. The decades-old “Working for Water” program has two goals: providing employment and development opportunities to disadvantaged individuals in rural areas, and managing invasive alien plants.

The Status of Biological Invasions and Their Management in South Africa is available here.

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.

CISP Decision: EAB Deregulation Is Not Useful – Too Much Is at Risk

 

 

EAB; Dave Cappaert

I blogged about APHIS’ proposal to stop regulating movement of objects that can transport the emerald ash borer on 28 September. At that time, I and the Center for Invasive Species Prevention were undecided. Now we have taken a firm position: We are sympathetic to the situation in which APHIS finds itself and are disappointed that APHIS’ efforts against EAB have not been as successful as hoped. However, we believe the quarantine continues to serve a useful purpose in protecting North America’s ash (and through the firewood regulatory effort, other resources) and that the analysis APHIS provides does not justify the proposed termination of the regulatory program. Making this regulatory change, based on absent and questionable scientific data, would set a terrible precedent.

 

Problems Arising from Poorly Substantiated Proposal

Here I provide some additional information on points I made in the blog in September.

1) The APHIS documents are completely unbalanced. They provide no analysis of the economic or environmental impact of  the regulatory changes that will allow the pest to spread more rapidly to the large areas of the country that are not yet infested.

The proposal concedes that emerald ash borer currently is known to occupy only about one quarter of the range of native Fraxinus species within the conterminous United States. As the Regulatory Flexibility Analysis states, numerous sawmills, firewood dealers, nurseries, logging/lumber companies, pallet manufacturing companies, and other establishments operate in these un-infested areas. The analysis makes no mention of the costs to millions of homeowners and property owners, thousands of municipal governments, etc., of removing and replacing ash trees on their properties that are killed by the ash borer as it spreads into new areas. The “analysis” makes no attempt to quantify impacts on any of these entities.

 

Examples of ash populations currently free of EAB include:

  • In North Dakota, 84% of the forest land area is dominated by hardwood forest types; one of the three major forest-type groups is elm/ash/cottonwood. Ash represent 38% of urban forest trees (Nowak, Hoehn, Crane, Bodine.)
  • In California, velvet ash (Fraxinus velutina) comprises 3.1% of the state’s street tree population (McPherson et al.). Because ash are large relative to other street trees, they provide about double the proportion of leaf cover (and associated environmental services) than the number of trees (Nowak, Hoehn, Crane, Weller, and Davila).
  • Portland, Oregon: ash represented 4% of urban trees (Portland Parks).

No mention is made of the additional range of Fraxinus species in Canada and Mexico that will be put at greater risk of invasion as the beetle spreads in the United States.

2) The proposal to rely on biocontrol to control EAB in the future lacks any scientific analysis of either the current biocontrol program’s effects or other possible program components.

APHIS is apparently relying on the conclusion by Duan et al. 2018 – based on models rather than field research findings – that larval and egg parasitism at about 60% would lead to a net population growth rate of EAB at a rate below replacement, therefore rapidly reducing EAB populations when such parasitism rates are accompanied by moderate to high levels of host plant resistance. If heavy woodpecker predation can be relied upon, a parasitism rate on EAB larvae of about 35% would be sufficient to achieve a similar reduction in the EAB population growth, even with limited levels of host resistance or tolerance.

However, scientific publications reviewing the impacts of the decade-old EAB biocontrol program present a mixed picture.

Our reading of several published studies indicate that two biocontrol agents (Oobius agrili and Tetrastichus planipennisi) appear to have established and spread in the northern reaches of the EAB’s U.S. range and southern Canada. At least some ash species appear to be regenerating well in some of those areas. However, it is too early to determine whether a third biocontrol agent (Spathius galinae) can protect the all-important remaining large trees, which have thicker bark. It is also too early to determine whether a different biocontrol agent (Spathius agrili) will have an impact on ash survival and regeneration in the middle latitudes (south of the 40th parallel).

APHIS does not discuss current or planned future efforts to seek and test biocontrol agents more likely to thrive in the South and West – to which EAB will spread. It is hoped – but not yet proved – that S. agrili will be more effective south of the 40th parallel. The article said nothing about possible agents that might be effective farther south or especially in the West.

Some scientists question the probable efficacy of biocontrol. For example, Showalter et al. note that “Despite the presence of a full complement of coevolved natural enemies in Asia, EAB has caused high mortality of North American ash species planted there … Biological control is best applied to systems in which the hosts can at least partially resist or tolerate non-native PIP [phytophagous insects and phytopathogens] attack, especially if negative density-dependent responses of natural enemies are slow relative to how long it takes the non-native PIP to kill trees.” Even Duan et al. 2018 agree that Asian ash species are more resistant (although they emphasize the large impact of natural enemies in Asia).

The scientific literature indicates that the impacts of egg parasitoid O. agrili remain uncertain (Abell et al.).

Duan et al. 2018 list and provide brief evaluations of nine possible biocontrol agents:

  • 2: status not revealed (Sclerodermus pupariae, Atanycolus nigriventris)
  • 2: disappointing efficacy to date (Spathius agrili, Oobius agrili)
  • 1: apparently efficacious in some geographies in smaller trees only (Tetrastichus planipennisi)
  • 1: promising in northern parts of EAB range but too early to evaluate (Spathius galinae)
  • 2: considered to have too broad a host range to be released (Tenerus, Xenoglena quadrisignata)
  • 1: release delayed pending further study (Oobius primorskyensis)

Even the impact of the most promising agent, Tetrastichus planipennisi, is not altogether clear. Duan et al. 2018 cite their life table analyses as indicating that T. planipennisi has contributed significantly to reducing net EAB population growth rates. They note a 90% reduction in EAB larval density. However, they say that this decline might be attributed in part to either the impact of the parasitoid or the general collapse of EAB populations following widespread mortality of overstory ash. (emphasis added)

3) Neither the proposal nor the supplementary materials provides  any information about the current allocation of available funding among APHIS’ program components or how those allocations will change if the proposal is adopted.

For example, APHIS has set a goal of releasing biocontrol agents in every county with a known EAB infestation where the agent populations can be sustained. The proposal states that, by the end of the 2017 field season, parasitoids had been released in 27 of 32 states and 2 of 3 provinces in which EAB is present (Duan et al. 2018). APHIS does not explain how the current funding allocation hampers achieving the stated goal.

4) The proposal and accompanying regulatory flexibility analysis provide  no information about whether APHIS will expand efforts supporting such other EAB impact minimization strategies as breeding trees resistant to emerald ash borer attack.

Even biocontrol practitioners (e.g., Duan et al. 2018 ) point to the importance of including breeding of resistant trees in the future efforts.

5) The proposal offers only vague promises about continuing federal efforts to minimize the risk that human transport of firewood will facilitate spread of the emerald ash borer or other tree pests.

Unfortunately, the impact of an outreach message depends heavily on having a simple, straightforward, unified message. Absent the EAB quarantine, which provides a nation-wide standard for firewood treatment, the “Don’t Move Firewood” campaign will be confronted by the task of trying to explain diverse messages and policies/rules issued by various states, counties, provinces, and managers of parks and other public lands. Hampered by this welter of messages, even the well-managed DMF campaign will struggle to persuade the public to help curtail spread via this pathway.

APHIS today published a set of “frequently asked questions” that address some of the issues raised in this blog. Go here to read the answers.

 

The Center for Invasive Species Prevention urges all who care about protecting North America’s native flora from non-native insects and diseases to submit comments on this proposed rule before the deadline on 19 November. This can be done by visiting here http://www.regulations.gov/#!docketDetail;D=APHIS-2017-0056.

 

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.

 

SOURCES

 

Abell, K.J., L.S. Bauer, J.J. Duan, R. Van Driesche. 2014. Long-term monitoring of the introduced emerald ash borer (Coleoptera: Buprestidae) egg parasitoid, Oobius agrili (Hymenoptera: Encyrtidae), in MI, USA and evaluation of a newly developed monitoring Technique. Biological Control 79 (2014) 36–42

Duan, J.J., L.S. Bauer, R.G. van Driesche, and J.R. Gould. 2018. Progress & Challenges of Protecting North American Ash Trees from the emerald ash borer Using Biological Control. Forests 2018, 9, 142; doi:10.3390/f9030142

McPherson, G., N. van Doorn, J. de Goedec. 2016. Structure, function and value of street trees in California, USA. USDA Forest Service, Pacific Southwest Research Station Urban Forestry and Urban Greening 17 2016 (104-115)

Nowak, D.J., R.E. Hoehn III, D.E. Crane, A.R. Bodine. Assessing Urban Forest Effects and Values of the Great Plains: Kansas, Nebraska, North Dakota, South Dakota. USDA Forest Service Northern Research Station Resource Bulletin NRS-71

Nowak, D.J., R.E. Hoehn III, D.E. Crane, L. Weller, A. Davila. Assessing Urban Forest Effects and Values: Los Angeles’ Urban Forest. USDA Forest Service Northern Research Station Resource Bulletin NRS-47

Portland Parks and Recreation Street Tree Inventory Findings 2015. www.portlandoregon.gov/parks/treeinventory

Showalter, D.N., K.F. Raffa, R.A. Sniezko, D.A. Herms, A.M. Liebhold,  J.A. Smith, P. Bonello. 2018. Strategic Development of Tree Resistance Against Forest Pathogen and Insect Invasions in Defense-Free Space. Frontiers in Ecology & Evolution

Scientists Document Alarming Declines in Insects

Luquillo Forest in Puerto Rico

While I usually blog about insects (and plant pathogens) that have invaded new ecosystems and are killing native plant species, I am aware that insects are numerous and vitally important components of the ecosystems in which they evolved. I join others in noting with concern evidence that insect populations in wide-apart areas have declined at very high rates. Insects appear to be affected by the Sixth Extinction Event (concept described here and here) as much as or possibly more than various vertebrate and plant taxonomic groups.

The Zoological Society of London and World Wildlife Fund published this week the 2016 version of the Living Planet report. Based on an analysis of 3,700 vertebrate species (birds, fish, mammals, amphibians and reptiles), the authors concluded that global wildlife populations have fallen by 58% since 1970 (Morelle; see references at the end of the blog).

Dirzo et al. in 2014 provided a very interesting discussion of the impacts of species’ declines in numbers and local extinctions – short of complete extinction. They asserted that “declines in numbers of individuals in local populations and changes in the composition of species in a community will generally cause greater impacts on ecosystem function than global extinctions. Dirzo et al. noted the importance of invertebrates, especially insects, in ecosystem functioning. They stated that the smaller fauna – including insects – “arguably are more functionally important” than charismatic megafauna and called for improved monitoring and study of such taxa, particularly invertebrates,

In their study, Dirzo et al. estimated that, since 1970, Lepidoptera – an order containing many important pollinators – had declined 35% in abundance globally over 40 years. Declines of other insect orders were considerably more. One study they cited found an overall 45% decline for all invertebrate populations over 35 years. More recent studies find decline rates that considerably exceed the estimated decline of 58% in global abundance of wild vertebrates over a 42-year period (Morelle; Hallmann et al.)

A year ago, Hallmann et al. reported a 76% decline in the biomass of flying insects over a 27-year period in Germany. There were seasonal variations; in midsummer, when insect biomass is highest, the decline was 82%. The study was carried out in nature protection areas – that is, places set aside and protected to conserve biological diversity. Hallmann et al. predict cascading effects on food webs and jeopardy to ecosystem services, including pollination, herbivory and breakdown of detritus, nutrient cycling and providing a food source for higher trophic levels such as birds, mammals and amphibians.

Hallmann et al. said that changes in weather, land use, and habitat characteristics could not explain this overall decline. Declines occurred in both nutrient-poor habitat types (e.g., heathlands, sandy grasslands, and dunes) and nutrient-rich habitats (grasslands, margins and wasteland), as well as in pioneer and shrub communities.

Another of the few studies looking at insects broadly, a study of flying insect biomass in the United Kingdom, found a biomass decline at only one of the four sites. Hallmann et al. note that the British researchers used considerably different sampling methods that targetted primarily high-flying insects (and caught mostly members of one fly family) whereas their own Malaise traps caught  insects flying close to the ground and a much wider diversity of taxa.

Taxon-specific studies have also found severe declines in insect populations.

Hallmann et al. concluded that the scale of decline in insect biomass – throughout the growing season, and irrespective of habitat type or landscape configuration – suggest that large-scale factors must be involved. As noted, their data did not support either landscape changes or climate change as explanatory factors – although they admit that they did not exhaustively analyze the full range of climatic variables that could potentially impact insect biomass. Hallmann et al. did think that agricultural intensification (e.g. pesticide usage, year-round tillage, increased use of fertilizers and frequency of agronomic measures) was a plausible cause of insect biomass decline given the reserves’ limited size in typically fragmented western-European landscapes. The noted that the protected areas might serve as insect sources which might be counterbalanced by the surrounding agricultural fields, which might act as sinks or ecological traps.

While Hallman et al. did not specify the types of pesticides being used by the German farmers operating near their study areas, in recent years there has been growing concern about widespread use of neonicotenoids, which appear to pose a threat to bees and possibly other insects. Three sources of information are the European Food Safety Agency; Xerxes Society; and petition pertaining to regulation of seeds treated by neonicotenoids submitted by the Center for Food Safety.

This month, Bradford Lister and Andrés García published a study that compared numbers of the insects and insectivores (birds, frogs, lizards) in Puerto Rico’s tropical rainforest in 2012 to results of Lister’s studies there in 1976 and 1977. Overall arthropod biomass in Puerto Rico’s Luquillo rainforest fell 10 to 60 times since 1970s (Lister and Garcia). Numbers of insects in the vegetation collected by sweep nets decreased to a fourth or an eighth of what they had been. The catch rate of ground-dwelling arthropods caught in sticky traps fell 60-fold (Guarino).

Lister and Garcia attribute the crash in arthropod numbers to climate change, especially rising maximum temperatures. They note that over the same 40-year period, the average high temperature in the rainforest increased by 4 degrees Fahrenheit (2oC). Lister and Garcia cite several studies indicating that tropical invertebrates are adapted to a narrow band of temperatures.

Lister and Garcia also measured declines among insect-feeding vertebrates. The biomass of anole lizards dropped by more than 30%. Some anole species disappeared from the interior forest (Guarino). Declines in number of coqui frogs (Eleutherodactylus spp) began in the 1970s. Currently, three of 16 species are extinct, and the remaining 13 species are classified in some category of endangered or threatened. Disease caused by the fungus Batrachochytrium dendrobatidis is not a factor at the elevations where study done.

Anolis gundlachi; photo by Joe King

Citing data from other researchers, Lister and Garcia report that numbers of insectivorous birds captured in mist nets fell 53% between 1990 and 2005.

Lister and Garcia sought to explain why there were simultaneous, long-term declines in arthropods, lizards, frogs, and birds over the past four decades in the relatively undisturbed rainforests of northeastern Puerto Rico. They concluded that climate warming has been a major factor driving reductions in arthropod abundance, and that these declines have in turn precipitated decreases in forest insectivores in a classic bottom-up cascade.

As supporting evidence, Lister and Garcia cite

(1) Declines across varied species and communities that occurred in parallel with rising temperatures.

(2) Simultaneous declines of all arthropod taxa in their own and others’ studies – pointing to an overriding environmental factor that has had ubiquitous, adverse effects on forest arthropods regardless of taxonomic affiliation, stratum occupied, or type of niche exploited.

(3) Declines in arthropod abundance that occurred despite major decreases in their predators – and, presumably, reduced predatory pressure..

Lister and Garcia note that there have been almost no significant human perturbations in the Luquillo forest since the 1930s, and that pesticide use in Puerto Rico fell nearly 80% over the past 40 years with the decrease in agricultural activity on the island. Some of the insect trend data came from studies carried out in the Luquillo Long Term Ecological Study site.

Lister and Garcia say that major weather perturbations have also had an impact. Over the 36-year time span, there have been five major hurricanes and eight severe droughts. They note that the island’s vegetation regenerated rapidly after hurricanes Hugo and Maria; insect populations regenerated rapidly after Hurricane Georges.  La Niña episodes led to an immediate increase in the abundance of canopy invertebrates, whereas El Niño episodes caused declines.

Of course, some insects are under threat from loss of their primary food plants to invasive species.  I note particularly the Palamedes swallowtail butterfly (Papilio palamedes), which depends on redbay and swamp bay, and an estimated 21 species of North American butterflies and moths believed to specialists or largely dependent on ash.

Palamedes swallowtail; photo by Vincent P. Lucas

 

 

In some cases, e.g., hemlock woolly adelgid and Asian longhorned beetle, neonicotenoids, specifically imidacloprid, is an essential tool to controlling a tree-killing invasive insect.

 

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.

SOURCES

Dirzo, R., H.S. Young, M. Galetti, G. Ceballos, N.J. B. Isaac, B. Collen. 2014. Defaunation in the Anthropocene. Science 345, 401

Guarino, B. 2018. ‘Hyperalarming’ study shows massive insect loss. 2018. The Washington Post October 15 2018

Hallmann CA, Sorg M, Jongejans E, Siepel H, Hofland N, Schwan H, et al. 2017. More than 75 percent decline over 27 years in total flying insect biomass in protected areas. PLoS ONE 12 (10): e0185809. https://doi.org/10.1371/journal. pone.0185809

Lister, B.C. and A. Garcia. 2018. Climate-driven declines in arthropod abundance restructure a rainforest food web. Proceedings of the National Academy of Sciences. http://www.pnas.org/content/early/2018/10/09/1722477115

Morelle, R. Science Correspondent, BBC News. 2018. World wildlife ‘falls by 58% in 40 years’ https://www.bbc.com/news/science-environment-37775622

 

 

South Africa’s unique flora put at risk by polyphagous shot hole borer

The polyphagous shothole borer (PSHB) and its fungal symbiont Fusarium euwallaceae are killing trees in South Africa as well as in California.

File:Erythrina humeana, blomme, Manie vd Schijff BT, b.jpg

Erythrina humeana in the Manie van der Schijff Botanical Garden, Pretoria

The pest complex’s presence was detected in August 2017 through an international sentinel tree program – the first detection of a tree pest under the program. Under the ‘sentinel plantings’ program, staff at botanical gardens and arboreta monitor their holdings – often exotic species growing outside of their natural range – and alert program partners when they detect damage caused by insects or pathogen not previously known to pose a risk. The International Plant Sentinel Network (IPSN) was launched in 2013. Botanical gardens and arboreta in South Africa joined the international effort in 2016 (Paap et al. 2918 – see list of sources at the end of this blog).

PSHB-caused tree mortality was initially detected in the KwaZulu-Natal National Botanical Gardens in Pietermaritzburg in August 2017. Affected trees were London Plane (Platanus x acerifolia) (Paap et al. 2018).

A beetle collected in 2012 in Durban, 50 km away from Pietermaritzburg, has now been determined to belong to the Euwallacea fornicatus species complex – indicating that the invasive insect and fungal species have been established in South Africa for several years (Paap et al. 2018). [Interestingly, 2012 is also the year that Dr. Akif Eskalen detected PSHB in a backyard avocado in southern California – setting off the detection, research, and slow-the-spread efforts now under way there.]

 

2018-10-01 PSHB - South Africa

locations of PSHB detections in South Africa; map from http://polyphagous-shot-hole-borer.co.za/

South African authorities were immediately concerned because the beetle-fungus complex attacks such a broad range of trees (species in 58 plant families).  Hosts include several species native to southern Africa – including cabbage tree (Cussonia spicata), common calpurnia (Calpurnia aurea), monkey plum (Diospyros lycioides),  two species of coraltree (Erythrina humeana and E. lysistemon), huilboerboon (Schotia brachypetala), honey flower (Melianthus major), two alders (Cunonia capensis and Nuxia floribunda), and red orchid bush (Bauhinia galpinii). Also at risk are several commercial crop trees such as avocado (Persea americana), macadamia nut (Macadamia integrifolia), pecan (Carya illinoinensis), peach (Prunus persica), orange (Citrus sinensis) and grapevine (Vitis vinifera) and several ornamentals, including maple, holly, wisteria, oak and Camellia (Paap et al. 2018).

South Africa is home to a highly unique flora. Indeed, the “Cape Floral Kingdom” is the smallest of the six floral regions on Earth. For more about South Africa’s botanical importance, go here or here.

Rapid spread of the beetle-fungus complex appears likely because one of the most important reproductive hosts, castor bean (Ricinus communis) is a widespread woody weed in the KwaZulu-Natal region (Paap et al. 2018).

By July 2018, it was clear that PSHB was established in several parts of the country (see map). In George — a city along the southern coast, due east of Capetown, the beetle and fungus are affecting a wide range of indigenous and exotic trees in the botanical garden and the region‚ including box elder‚ Chinese and Japanese maple‚ oak‚ plane trees‚ Kapok trees‚ paper bark acacia‚ wild plum‚ dwarf corral and common corral (Chambers 2018).

In Johannesburg, a concerned citizen tracking the pest complex’ spread thinks that the beetle-fungus combination has already infested well over 100,000 of Johannesburg’s trees and is on track to damage or kill millions more (there are an estimated 6 – 10 million trees in Johannesburg, nearly all exotic) (Weltz 2018).

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.

SOURCES

Chambers, D.  “A 2mm beetle is laying waste to George’s trees” Sunday Times. 30 May 2018 https://www.timeslive.co.za/news/sci-tech/2018-05-30-a-2mm-beetle-is-laying-waste-to-georges-trees/

Johannesburg Urban Forest Alliance. The Shot Hole Borer Beetle is destroying our Urban Forest http://www.jufa.org.za/pshb.html

Paap, T., Z.W. de Beer, D. Migliorini, W.J. Nel,  M.J. Wingfield. 2018. Australasian Plant Pathology https://doi.org/10.1007/s13313-018-0545-0 https://link.springer.com/article/10.1007/s13313-018-0545-0

Weltz, A. Beetle Mania The Nasty Insect that is Killing the Trees of Johannesburg. Yale Environment 360; Published at the Yale School of Forestry and Environmental Studies. https://e360.yale.edu/features/beetle-mania-the-nasty-insect-that-is-killing-the-trees-of-johannesburg