forest pests – Page 17 – Center for Invasive Species Prevention

Mixed News on Pest Dangers

‘ōhi‘a tree in flower

Worsening Threats to Hawaii’s Rich – and Rare — Native Forests

As I have written in previous blogs (October 2015; October 2016), the beautiful ‘ōhi‘a lehua (Metrosideros polymorpha) tree is ecologically and culturally the most important tree n the Hawaiian Islands. ‘Ōhi‘a trees dominate approximately 80% of Hawai`i’s remaining native forest. Loss of the species could result in significant changes to the structure, composition, and, potentially, the function, of forests on a landscape level. ‘Ōhi‘a forests are home to the Islands’ one native terrestrial mammal (Hawaiian hoary bat) as well as about 100 plant species listed as endangered by the U.S. Fish and Wildlife Service. Also 30 species of forest birds – in particular, the unique endemic honeycreeper subfamily — depend on ‘ōhi‘a. Eighteen of 19 extant Hawaiian honeycreepers in the main Hawaiian islands, including 12 of 13 bird species listed as endangered by the U.S. Fish and Wildlife Service, depend on ‘ōhi‘a for critical habitat.

Unfortunately, the threat to ‘ōhi‘a trees from three fungi appears to be rising.

“Rapid ‘ōhi‘a death” is caused by two fungi, Ceratocystis lukuohia and C. huliohia (formerly considered to be strains of Ceratocystis fimbriata). Rapid ‘ōhi‘a death has spread since 2010 to most districts of one island: Hawai`i or the “Big” Island. The total area affected is 135,000 acres. Still, most ʻōhiʻa forest on Hawai`i is still healthy, and the disease has not yet been found on any of the other islands. Scientists have begun exploring trees’ varying susceptibility and the possibility of breeding more resistant trees to be used for restoration. For more information, read the recently updated description here.

Ōhi‘a trees are also under attack by a third introduced fungus, called ‘ōhi‘a rust, guava rust, or myrtle rust. This is caused by Austropuccinia psidii (formerly named Puccinia psidii). Ōhi‘a rust has been established on all the Hawaiian islands since 2005. Until recently, it had caused little damage to ‘ōhi‘a – although it attacks several additional native plant species and has devastated the endangered endemic plant Eugenia koolauensis. This shrub can reproduce now only in nurseries where it can be treated for the fungus. In late 2017, an outbreak of the disease caused widespread defoliation and mortality of ‘ōhi‘a across hundreds of acres in at least four locations on windward portions of two islands, O‘ahu and Moloka‘i. It is not yet known whether this new damage resulted from introduction of a new, more virulent strain or from a period of unusually wet weather creating more favorable conditions for the fungus. For more information, read the recently updated description here. (Myrtle rust threatens plants in the Myrtaceae family across the Pacific; more than 450 species have been identified as hosts. Some species in Australia have been severely affected.)

laurel-wilt killed swamp bay in the Everglades

Severe Attacks on Redbay and other Laurels in the Southeast.

Since the turn of the century, redbay trees (Persea borbonia) in coastal regions of the Southeast have been dying because of laurel wilt disease. This is caused by the fungus Raffaelea lauricola, which in turn is vectored by the redbay ambrosia beetle (Xyleborus glabratus). Both the beetle and disease have spread rapidly since there were detected in 2002 near Savannah, Georgia. The disease now is found in eight states, reaching from eastern North Carolina south along most of the Florida peninsula; across the Gulf states with several locations in Alabama and Mississippi; and to isolated outbreaks in Louisiana and Texas. Already an estimated 320 million trees – nearly one-third of all redbays – have been killed. Mortality is highest where the disease first became established: Georgia (two-thirds of redbays killed), South Carolina (42% of redbays killed), and Florida (36% of redbays killed). In contrast, redbay mortality appears to be quite low in Alabama and Mississippi although mortality caused by disease might have been masked by application of fire or other silvicultural practices.

Other forest trees and shrubs in the Lauraceae family are also at risk. These include swamp bay (Persea palustris), which contribute greatly to the biological diversity of the “tree islands” scattered through the Everglades; sassafras (Sassafras albidum), which occupies a large range reaching into Michigan and southern New England; and two rare species – pondspice (Litsea aestivalis) and the federally listed pondberry (Lindera melissifolia). Northern spicebush (Lindera benzoin), another shrub in the Lauraceae family, does not attract the beetle so it is unlikely to sustain disease. In the West, California bay laurel has been determined by laboratory studies to be vulnerable.

Redbay is important to wildlife and has some use in horticulture. However, most attention has focused on the threat to avocados (Persea americana); the disease was detected in commercial orchards in 2012.

Concerned about loss of this ecologically important tree, scientists have begun efforts to breed redbays that are resistant to, or tolerant of, the disease. In addition to efforts by university scientists, the newly formed consortium Forest.Health (https://forest.health/) has listed redbay as a high priority for resistance breeding. For more information, read the updated description here.

initial damage caused by Kuroshio shot hole borer in Tijuana River Valley; I lack access to photos of recovery. Photo by John Boland

Hope in southern California – possible ecological limits to shot hole borer / fungal disease

John Boland, an ecologist who has studied southern California riparian wetlands for decades, reports that willows in the Tijuana River are recovering from attack by the Kuroshio shot hole borer and the fungi it vectors. After two years, the beetle-vectored disease had infested 88% of the willows in the valley (a total of 355,510 trees). An estimated 24% of the willows had been killed (95,791 trees). Nearly all of the infested and killed trees grew in the wettest parts of the riparian forests. (Photo above illustrates damage at this stage of the invasion.)

However, 71,280 of the willow trees have resprouted. By late 2017, these resprouts had created a new forest canopy that was about 5 meters tall. (Previously, the canopy had been about 20 meters tall). The median rate of infestation of these resprouting willows was 6% in 2017, down from 97% in 2015-2016. Some insect boring holes have healed.

In contrast, willows growing in drier parts of the valley were rarely attacked initially, but are now increasingly infested. In 2017, the median infestation rate was 78%, up from 9% in 2015-16. However, few trees have been killed.

Dr. Boland believes that the severity of the initial attack reflected the vulnerability of “soft trees”. Trees growing in the wetter parts of the Tijuana River Valley are inundated by sewage from the Mexican city. As a result of this artificial fertilization, they grow quickly and their wood is less dense.

For more information about the Kuroshio and phytophagous shot hole borers and their associated fungi, read the description here.. Dr. Boland’s study has been made available to participants in the southern California emerging forest pest groups but I cannot find a publicly available source on the Web.

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.

Posted by Faith Campbell

APHIS Nursery Stock Regulations (Q-37) – Modernization Finally Completed!

citrus longhorned beetle – entered country several times in imported bonzai plants

After about 20 years, APHIS has finalized important changes to the regulations which govern imports of living plants (what they call “plants for planting”; the regulation is sometimes called “the Quarantine 37” rule). The new regulation takes effect on April, 18, 2018.

I congratulate APHIS on this important achievement!

[Twenty years is a long time – so changes happen. When APHIS released its Advance Notice of Proposed Rulemaking (ANPR) in December 2004 and its proposed rule in April 2013, I was employed by The Nature Conservancy and submitted comments for that organization. I will refer to those earlier comments in this blog. However, I now represent the Center for Invasive Species Prevention, so my comments here on the final regulations reflect the position of CISP, not the Conservancy.]

APHIS’ 2004 ANPR came after years of preparation. Then, more than eight years passed until the formal proposal was published on April 25, 2013. Comments were accepted from the public until January 30, 2014. During this nine-month period, 17 entities commented, including producers’ organizations, state departments of agriculture, a foreign phytosanitary agency (The Netherlands), private citizens, and The Nature Conservancy. [You can view the ANPR and proposal, comments on these documents, and APHIS’ response here — although you need to click on “Restructuring of Regulations on the Importation of Plants for Planting” and then “Open Docket Folder” to pursue the older documents.]

In the beginning, APHIS had a few goals it hoped to achieve: to allow the agency to respond more quickly to new pest threats, to apply practices that are more effective at detecting pests than visual inspection at points of import, and to shift much of the burden of preventing pest introductions from the importer and APHIS to the exporter.

Progress has been made toward some of these goals outside this rule-making. APHIS instituted a process to temporarily prohibit importation of plants deemed to pose an identifiable risk until a pest risk assessment has been completed (the NAPPRA process). APHIS has further enhanced its ability to act quickly when a pest risk is perceived by relying increasingly on “Federal Orders”.

At the same time, APHIS participated actively in efforts by international phytosanitary professionals to adopt new “standards.” These define a new approach to ensure that plants in international trade are (nearly) pest-free. Both the North American Plant Protection Organization’s regional standard (RSPM#24) and the International Plant Protection Organization’s global standard (ISPM#36) envision a system under which countries would no longer rely primarily on inspections at ports-of-entry. Instead, they would negotiate with the supplier or exporting country to develop programs to certify that growers’ pest management programs are effective. Both standards detailed: 1) how the place of production might manage pest risk and ensure traceability of plants; 2) how the importing and exporting countries might collaborate to administer the program; 3) how audits (including site visits) would ensure the program’s efficacy; and 4) what actions various parties might take in cases of noncompliance.

It was hoped that these international standards would lead to widespread adoption of “integrated pest management programs” composed of similar requirements – similar to the impact of ISPM#15 for wood packaging. However, living plants are more complex pest vectors than the wooden boards of crates and pallets, so each country was expected to negotiate its own specific programs – something not encouraged for wood packaging.

APHIS’ decades-long effort to amend its regulations is warranted because of the high risk of non-native insects and – especially – pathogens being introduced via international trade in living plants. U.S. examples include white pine blister rust, chestnut blight, dogwood anthracnose, and sudden oak death (all described briefly here )

dogwood anthracnose

According to Liebhold et al. 2012 (full reference at end of blog), 12% of incoming plant shipments in 2009 were infested by a quarantine pest. This is an approach rate that is 100 times greater than the 0.1% rate documented for wood packaging (Haack et al. 2014). I have discussed the living plant introductory pathway and efforts up to 2014 to get it under control in my report, Fading Forests III.

Shortcomings of the Final Q 37 Rule

So – how well does this final rule meet APHIS’ objectives?

First, will it shift much of the burden of preventing new pest introductions from the importer and APHIS to the exporter, while ensuring the system’s efficacy? In my view, on behalf of CISP, it falls short.

The new rule sets up a process under which APHIS might require that some types of imported plants be produced and shipped under specified conditions intended to reduce pest risk. However, non-American entities have little incentive to protect America’s natural and agricultural resources and from invasive species. So any new process needs severe penalties for violators.

We have seen how widespread and persistent compliance failures are for wood packaging under ISPM#15. http://nivemnic.us/wood-packaging-again-11-years-after-ispm15-problems-persist/ For this reason, I (on behalf of the Conservancy) had suggested that APHIS formally adopt a specific goal of “no new introductions”. I recognized that this goal was unachievable per se, but suggested that it should stand as a challenge and be the basis for adopting stringent restrictions on plant imports. I suggested limiting plant imports to those either a) produced under integrated pest management measures systems (verified by third-party certification) or b) plants brought into facilities operating under post-entry quarantine conditions — and following other best management practices that had been developed and supervised by independent, scientifically-based bodies.

In my current view, APHIS’ regulation falls far short of either this goal of shifting burdens or setting a truly stringent requirement. In fact, APHIS has explicitly backed away from its own original goals and procedures.

The new regulation does authorize APHIS to choose to set up import programs under which the exporting country agrees to produce plants for the U.S. market under a system of integrated pest risk management measures (IPRMM) approved by APHIS. In accordance with the international standards, the programs established under this new power will address how the place of production will manage pest risk and ensure traceability of plants; how APHIS and the exporting country will administer the program; how plant brokers will ensure plants remain pest-free while in their custody; how audits will be performed to ensure program efficacy; and what actions various parties will take in cases of noncompliance.

How efficacious this new approach will be in preventing new introductions will depend on how aggressive APHIS is in both choosing the plant taxa and places of-origin to be managed under such IPRMM programs and in negotiating the specific terms of the program with the exporting country.

It is discouraging that APHIS has ratcheted down how frequently it expects to rely on the IPRMM approach. In the explanatory material accompanying the final regulation, APHIS clarifies that did not intend that IPRMM would be used for all imports of living plants. The IPRMM framework is described as only one of several means to achieve the goal of preventing introduction of quarantine pests. APHIS will choose the “least restrictive measures” needed to prevent introduction of quarantine pests. To clarify its position, APHIS changed the introductory text to indicate that IPRMM will be applied when such measures are necessary to mitigate risk – that is, “when the pest risk associated with the importation of a type of plants for planting can only be addressed through use of integrated measures.” [Emphases added]

The final rule is also discouraging in some of its specifics.

Whereas the draft regulation specified steps that places of production must take to ensure traceability of the plants they produce, in the final regulation the traceability elements specified in each IPRMM agreement will depend on the nature of the quarantine pests to be managed. Again, APHIS seeks to ensure that its requirements are not unnecessarily restrictive.
Although the international standard had specified severe penalties when a grower or broker violated the terms of the IPRMM agreement, APHIS proposed to base the regulatory responses to program failures on existing bilateral agreements with the exporting country. Despite the Conservancy’s plea that APHIS follow ISPM#36 in adopting more specific and severe penalties, APHIS has not done so. The one bright spot is that APHIS may verify the efficacy of any remedial measures imposed by the phytosanitary agency of the exporting country to correct problems at the non-compliant place of production. [Emphasis added]
APHIS is relaxing the detailed requirements for state post-entry quarantine agreements – despite the Conservancy’s concern that such agreements’ provisions could be influenced by political pressure and other nonscientific factors.

Two Improvements

I am pleased that APHIS has retained requirements applied to plant brokers, despite one commenter’s objections. Brokers handling international shipments of plants grown under an IPRMM program must both handle the plants themselves in ways that prevent infestation during shipment and maintain the integrity of documentation certifying the origin of the plants. A weakness, in my current view, is that APHIS will allow brokers to mix consignments of plants from more than one producer operating under the IPRMM program. APHIS does warn that if non-compliant (infested) plants are detected at import, all the producers whose plants were in the shipment would be subject to destruction, treatment, or re-export.

A major improvement under the new regulation is that APHIS will now operate under streamlined procedures when it wishes to amend the requirements for importing particular plants (whether a taxon, a “type”, or a country of origin). Until now, APHIS has been able to make such changes only through the cumbersome rulemaking process, Instead, APHIS will now issue a public notice, accept public comments, and then specify the new requirements through amendment of the “Plants for Planting Manual” [ https://www.aphis.usda.gov/import_export/plants/Manuals/ports/downloads/plants_for_planting.pdf ] APHIS estimates that such changes can be finalized four months faster under the new procedure.

A Final Caveat

Finally, APHIS needs to be able to measure what effect the new procedures have on preventing pest introductions. Such measurement depends on a statistically sound monitoring scheme. APHIS has stated in some documents that the current Agriculture Quarantine Inspection Monitoring (AQIM) system doesn’t serve this purpose. APHIS needs to develop a valid monitoring program.

References

Haack RA, Britton KO, Brockerhoff EG, Cavey JF, Garrett LJ, et al. (2014) Effectiveness of the International Phytosanitary Standard ISPM No. 15 on Reducing Wood Borer Infestation Rates in Wood Packaging Material Entering the United States. PLoS ONE 9(5): e96611. doi:10.1371/journal.pone.0096611

Liebhold, A.M., E.G. Brockerhoff, L.J. Garrett, J.L. Parke, and K.O. Britton. 2012. Live Plant Imports: the Major Pathway for Forest Insect and Pathogen Invasions of the US. www.frontiersinecology.org

Posted by Faith Campbell

Action on the Threat from Phytophthoras in Restoration Plantings

In July 2016 I blogged about the risk that native plant nurseries in California might spread various Phytophthoras to natural areas through use of infected plants used in restoration plantings.

In response to this threat, the California Oak Mortality Task Force has formed a Phytophthoras in Native Habitats Work Group to protect wildlands and assist the restoration industry in adopting practices to ensure they are producing “clean” plants.

The California Native Plant society (CNPS) adopted a policy to promote propagation practices that help prevent plant diseases. CNPS also established its own Ad Hoc Committee on Phytophthoras to address the same threat.

Numerous resources, including guidelines for nursery management, restoration plantings, summaries of committee meetings, photographs, etc., are posted at this website.

As I described in the July 2016 blog, Phytophthora pathogens have been detected in nurseries in other states, including Maryland, Minnesota, North Carolina, Oregon, and Tennessee. Doubtless nurseries in additional states also harbor damaging pathogens.

I’m not aware of action by regulatory officials, nursery owners, or conservation practitioners in these other states to evaluate and address this threat? Are you?

Posted by Faith Campbell

EU1 Genetic Lineage of Sudden Oak Death Persists in Oregon, Threatens Douglas-fir

In 2015 I blogged about Oregon’s first-ever detection of the EU1 strain of the sudden oak death pathogen – Phytophthora ramorum – in the forest. We know that P. ramorum has four genetic strains. Until this discovery, all P. ramorum infections in North American forests belonged to the NA1 strain.

In response to the 2015 detection, the Oregon Department of Forestry immediately began efforts to eradicate the EU1 infestation. This program was funded in part by the USDA Forest Service Forest Health Protection program and APHIS.

Unfortunately, the EU1 strain persists – and has spread. In 2017, six of ten streams in the state found to harbor P. ramorum contained the EU1 lineage. A total of 119 trees infected by the EU1 strain grow in five separate sites. Infections on 43 additional trees are still being tested to determine their lineages. Under the Oregon eradication protocols, 371 acres of private and state-owned properties will be affected by management targetting the EU1 lineage.

This news is alarming for two reasons.

First, the EU1 lineage is more aggressive than the more common NA1 strain. For example, the EU1 lineage in Europe kills several types of conifers, including western hemlock (Tsuga heterophylla). In Oregon, the EU1 strain has been found to infect both Douglas-fir (Pseudotsuga menziesii) and grand fir (Abies grandis) (LeBoldus et al. 2017). Douglas-fir is, of course, the foundation of the wood products industry in the West.

Second, the EU1 lineage is of the opposite mating type as NA1, creating the potential for sexual reproduction and increased variability in the pathogen population. (Sexual reproduction in P. ramorum can occur only when opposite mating types meet; in the absence if opposite mating types, all reproduction is clonal.)

The Oregon Department of Forestry continues eradication efforts. The program has been completed at one site; efforts at the other four known sites are a priority this year. Funding and resource constraints mean that sites infected by the more widespread NA1 strain are not likely to be treated this year. (ODF has approximately $1,375,000 available for eradication efforts in FY 2017-18.) No mention has been made of whether the USDA Forest Service or APHIS will provide assistance.

COMTF Newsletter March 2018

The EU1 pathogen probably spread to the original infected tree from a small private nursery nearby. That nursery had been reported to be infected with the EU1 lineage of P. ramorum in 2012. As I noted in my earlier blog, this infection confirms fears that contaminated nurseries can spread the pathogen into the forest.

SOURCES

California Oak Mortality Task Force newsletter [http://www.suddenoakdeath.org/news-and-events/newsletter-archive/ ] April 2015 and March 2018.

LeBoldus, J.M.; Sondreli, K.L.; Sutton, W.; Reeser, P.; Navarro, S.; Kanaskie, A.; and Grünwald, N.J. 2018. First Report of P ram Lineage EU1 Infecting Douglas-Fir and Grand Fir in OR. Plant Disease. 102(2): 455. [summarized in the California Oak Mortality Task Force Newsletter, March 2018, available here. [link]

Posted by Faith Campbell

Help Fund Priority Tree-Protection Programs

Your help is needed to prevent cuts to vitally important programs that protect America’s forests from non-native insects and pathogens.

USDA APHIS

The USDA Animal and Plant Health Inspection Service (APHIS) is responsible for preventing introductions of new pest that threaten plants – including forest trees — and for carrying out programs to eradicate or contain those that slip through their safeguards. I have blogged often about the unacceptable level of risk that the agency accepts, which enables new pests to be introduced. For examples, search “international trade” or “invasive species policy” on this site.

To see the President’s budget proposal, download the USDA budget justification here; search for “animal and plant”]

APHIS’ most important programs to counter tree-killing pests are funded through the “tree and wood pest” and “specialty crops” accounts. The former account pays for efforts to eradicate the Asian longhorned beetle (ALB), and to slow the spread of the emerald ash borer (EAB). As part of the latter program, it also funds APHIS’ engagement in regulating movement of firewood from quarantined areas.

For several years, the “tree and wood pest” account has been funded at $54 million. This is not sufficient, but we now face worse. The Administration has proposed cutting funding for the “tree and wood pest” account by more than half (from $54 million to $25 million). This level of funding would not even maintain the ALB eradication effort!

USDA smokejumpers search for ALB

The specialty crop account funds APHIS program to prevent sudden oak death from being spread via the nursery trade. It is slated for a cut of 18.7% (from $172 million to $139 million).

The Administration has proposed cuts to other programs that also would undermine protection for forest trees:

24% cut (from $21 million to $16 million) to methods development. This is the program under which APHIS develops new techniques for detecting, monitoring, and controlling pests.
5% cut (from $27 million to $22 million) to funding for pest detection. It is counterproductive to reduce programs to detect pests, since early discovery is crucial to successful eradication.

APHIS funds work on the spotted lanternfly (in Pennsylvania) and the polyphagous and Kuroshio shot hole borers (in California) through Section 10007 of the Farm Bill. The Farm Bill sets a funding limit for each year that is not subject to annual appropriations so these programs are not at immediate risk of being defunded. Also, APHIS can request emergency funding from the Commodity Credit Corporation. In February 2018, APHIS obtained $17.5 million in such emergency funding to support enhanced eradication efforts targetting spotted lanternfly in Pennsylvania. APHIS will continue to rely on Section 10007 funds to address this pest in other states to which it has apparently spread (Virginia, possibly Delaware, Maryland, and New Jersey).

Please ask your Congressional Representative and Senators to oppose these proposed cuts!

APHIS receives its annual appropriation through the Agriculture Appropriations bill. This legislation is written by the House and Senate Agriculture Appropriations subcommittees. Members of these subcommittees are listed below. These legislators are especially influential in determining funding for APHIS programs.

House:

Robert Aderholt, Alabama, Chairman
Kevin Yoder, Kansas
Tom Rooney, Florida
David Valadao, California
Andy Harris, Maryland
David Young, Iowa
Steven Palazzo, Mississippi
Sanford Bishop, Georgia, Ranking Member
Rosa DeLauro, Connecticut
Chellie Pingree, Maine
Mark Pocan, Wisconsin

Senate:

John Hoeven, North Dakota
Thad Cochran, Mississippi
Mitch McConnell, Kentucky
Susan Collins, Maine
Roy Blunt, Missouri
Jerry Moran, Kansas,
Marco Rubio, Florida
Jeff Merkley, Oregon
Diane Feinstein, California
Jon Tester, Montana
Tom Udall, New Mexico
Patrick Leahy, Vermont
Tammy Baldwin, Illinois

USDA Forest Service

The Administration has proposed damaging decreases in both research and management programs that target non-native insects and pathogens.

Research & Development

The research budget proposal contains numerous figures which don’t appear to add up. I have contacted USFS budget officials to learn how to understand these apparent discrepancies. To read the overall USFS budget, go here.

The budget proposes cutting overall research by 14.8% — from $306,216,000 to $260,800,000. According to the table on p. 30 of the budget justification, invasive species research is allocated $28,558,000. The text says this is 17% of the total Research budget – but my calculation is that it is 10.9%. The discrepancy apparently resulted from a failure to adjust to last-minute changes in funding amounts. The invasive species allocation is described as being a decrease of $3,217,000 from the FY18 figure. Despite these cuts, invasive species are described as one of six “strategic program areas”.

The Forest Service provides a table breaking out funding for work by the research stations on more than a dozen individual pest species or groups of species. The table listing this spending (on pp. 45-46) shows a total of $7,591,000 for FY18 and $6,271,000 for FY 19. The $22 million remaining in the “invasive species” program is apparently spent by staff at headquarters or possibly regional offices. I am trying to find out what this larger category of expenditures includes.

Furthermore, the $6.2 million total includes programs targetting several native species (western bark beetles, southern pine beetle), as well as subterranean termites and invasive plants. If one subtracts expenditures for those species, only $3,091,000 is allocated to non-native tree-killing insects and pathogens in FY18 and $3,252,000 for FY19. This is 1.2% of the overall research budget. Cuts for the individual species range from 19% to 21%.

Since 2010, total funding for research on the ten specified non-native insects and pathogens has fallen by more than 60% — from about $8 million to $3 million. The table listing expenditures on individual species cannot be complete; for example, it does not include efforts to breed pest-resistant elm and beech. Nor does it include recently detected pests, such as spotted lanternfly and polyphagous and Kuroshio shot hole borers – which I hope the Forest Service is studying.

The budget foresees a 42% cut in staff-years from FY18 to FY19 – from 1,469 to 855. USFS Research staffs have been falling for several years (illustrative graph is available in Chapter 6 of Fading Forests III here.) Supportive funds to cover costs of travel, fieldwork, student assistants, and grants to universities have also fallen precipitously, further impeding research efforts.

State & Private/ Forest Health Management

The Administration’s proposed budget for the USFS proposes a cut of 8.5% in the program that actually combats damaging pests. The cut to funding for pest-management projects on federal lands is 6.5% ($55,123,000 to $51,495,000). The cut to funding for work on state and private lands (the “cooperative lands” account) is 11% ($38,735,000 to $34,376,000). The budget assumes corresponding cuts to staff by 11% (341 staff-years).

The justification notes that, with this budget, the Service will be able to treat fewer acres, so the agency will “focus on the most pressing needs for forest restoration and reducing communities’ risk to wildfire”.

I consider the ostensible focus to be highly misguided. Even the budget justification concedes that pests and pathogens cause billions of dollars of damage each year and that pest-management methods are more effective when treatments are applied regardless of land ownership. Indeed, history shows that pests enter and first establish in urban and suburban areas that receive the imports that transport pests, like wood packaging or nursery stock. If the USFS fails to help counter pests at these introduction sites, it dooms itself to dealing with well-established invaders – at best an enormous and expensive effort, at worst, failure.

As noted earlier, the table on pp. 45-46 lists spending on individual pest species. The total given is $21,356,000 in FY18; the proposal cuts spending to $19,407,000 in FY19. As above, I subtract expenditures for native species (western bark beetles, southern pine beetle), subterranean termites, and invasive plants. The resulting subtotals are $12,874,000 for FY18 and $11,681,000 for FY19. As usual, the gypsy moth receives the bulk of the expenditures — 62% for both years. To meet the lower total mandated for FY19, spending is cut 8 – 9% for each non-native species listed.

In FY10, spending on the 11 named non-native insects and pathogens was $24 million. By FY18, it had fallen by nearly 50% — to $12.8 million. Pest species suffering the largest cuts are the Asian longhorned beetle (zeroed out), hemlock woolly adelgid (52% decrease), oak wilt (27% decrease), sudden oak death (18% decrease), and the combination of goldspotted oak borer, thousand cankers disease, and laurel wilt (15% decrease). The budget justification document does not provide sufficient information to allow me to judge the wisdom of the individual cuts.

It is troubling that the table makes no mention of other invaders – e.g., polyphagous & Kuroshio shot hole borers, spotted lanternfly, velvet longhorned beetle, winter moth (this last is mentioned in the narrative). The first four are relatively new pests with costs that could impose catastrophic damage if they are not countered by adequate programs.

Urban Forestry and International Programs

The budget proposes to eliminate funding for both urban forestry and international programs. I consider both programs important to invasive species management. The former strengthens forestry programs and public support for them in the very places where new pests are most likely to be introduced! The international program supports cooperation with foresters in foreign countries – the sources for potentially invasive insects and pathogens, as well as locales that can provide possible agents for biological control.

Please ask your Congressional Representative and Senators to oppose these proposed cuts!

The Forest Service receives its annual appropriation through the Interior Appropriations bill. This legislation is written by the House and Senate Interior Appropriations subcommittees. Members of these subcommittees are listed below. Again, please let them know of your concerns.

House:

Ken Calvert, California, Chairman
Mike Simpson, Idaho
Tom Cole, Oklahoma
David Joyce, Ohio
Chris Stewart, Utah, Vice Chair
Mark Amodei, Nevada
Evan Jenkins, West Virginia
Betty McCollum, Minnesota, Ranking Member
Chellie Pingree, Maine
Derek Kilmer, Washington
Marcy Kaptur, Ohio

Senate:

Lisa Murkowski, Alaska
Thad Cochran, Mississippi
Lamar Alexander, Tennessee
Roy Blunt, Missouri
John Hoeven, North Dakota
Mitch McConnell, Kentucky
Steve Daines, Montana
Shelly Moore Capito, West Virginia
Diane Feinstein, California
Patrick Leahy, Vermont
Jack Reed, Rhode Island
John Tester, Montana
Jeff Merkley, Oregon
Chris Van Hollen, Maryland

Posted by Faith Campbell

New study evaluates “candidate pool” from which invasive species might come

Campanula latifolia – one of the species detected as an “emerging” invasive species in the database relied upon by the authors of the study

The authors of a new study note that officials managing invasive species programs rely largely on knowledge of a species’ previous invasion history to predict its level of threat in the geographic area under their responsibility. This approach does not work with the many introduced species that have no history of a previous detected invasion. Hanno Seebens and 49 coauthors – including tree-pest experts Eckehard G. Brockerhoff, Marc Kenis, Andrew M. Liebhold, and Alain Roques — have sought to figure out how great a handicap that lack of data is. See “Global rise in emerging alien species results from increased accessibility of new source.” The study is available for $10 here. Figures, tables, and references are available without charge.

The study used a database of 45,984 first records of establishment of 16,019 species belonging to the following major taxonomic groups: vascular plants, mammals, birds, fishes, insects, crustaceans, mollusks, and other invertebrates.

Last year, many of the same scientists, relying on the same database, found that the rate of new introductions of alien species has risen rapidly since about 1800 – and shows no sign of slowing down. The adoption of national and international biosecurity measures during the 20th century have slowed introductions – but they are not sufficiently effective, especially regarding those plants and animals that are introduced primarily accidentally as stowaways on transport vectors or contaminants of commodities (e.g., algae, insects, crustaceans, mollusks and other invertebrates). The 2017 study found a strong correlation between these “accidental” alien species’ spread and the market value of goods imported into the region of interest. For that study, go here. I blogged about the findings on 1 March 2017 – here.

In the new 2018 article, the scientists found that even after many centuries of invasions the rate of emerging alien species is still high. Across all taxonomic groups, one out of four detections during 2000 – 2005 was of a species that had not been previously recorded anywhere as alien. Detections of “new” or “emerging” aliens is occurring at an even higher rate for some taxonomic groups. But new detections of insects fit the average – every fourth detection during 2000 – 2005 was of a species not previously recorded outside its native range.

The authors conclude that the continuing high proportion of “emerging” alien species is best explained by the interplay of 1) the incorporation into the pool of potential alien species of species native to regions formerly not accessible to traders; 2) increases in introduction rates due to higher import volumes; and 3) probably rising establishment rates as a consequence of land degradation that facilitates establishment in recipient regions. This process compensates for the decrease of new invaders from historically important source regions – from which potentially invasive species have presumably already taken advantage of pathways and been recorded as introduced somewhere.

emerald ash borer Agrilus planipennis – one of the species in the database of “emerging” invasive species

The number of insect species in the database candidate species pool is 20,611 species – an admittedly small fraction of all insects (for example, there are more than 350,000 beetle species worldwide). Twenty-four percent of these insect species have already been established somewhere outside their native ranges. However, the authors note that data gaps – which are larger for some taxonomic groups and geographic regions – mean that the number of actual “first” introductions is probably larger than records indicate, and consequently the estimated size of the candidate species pools may also be higher. Indeed, the paper does not attempt to estimate the actual size of the invasive species “pool” for insects.

The authors analyzed the importance of eight factors – temperature, relative humidity, import values, three land-use categories, number of botanical gardens, and human population size – in explaining the continued high number of “emerging” invaders detected in recent years. While these factors were explanatory for some taxonomic groups, they had a very low predictive value for insects.

For vascular plants, every third record of an introduction in 2000 – 2005 was of an “emerging” alien species. Interestingly, the number of botanical gardens in a country was a significant predictor for emerging alien vascular plants. However, as the authors of the article point out, reliance on this factor ignores the probable importance of other contributors such as the number of species planted in the receiving country; similarities between source and receiving environments; and introductions by acclimatization societies, European explorers or settlers, and plant hunters.

Acer ginnala –one of the species detected as an “emerging” invasive species in the database; photo by J. Weisenhorn, University of Minnesota extension

In any case, lots of previously undetected alien species are detected each year. In this database, 58% of the species had a single record; 86% of all species have no more than two first records in countries on the same continent. The large number of species with only one or two records led the authors to conclude that most species will not spread widely. I question that conclusion because species often require some time to spread to new locations – either local or distant. The authors do admit that they are unable to determine which species have a high potential for spread.

ash trees at the St. Louis arch – before arrival of emerald ash borer

The continued high rate of introduction of new species leads the authors to estimate that between 1% and 16% of all species on Earth – depending on the taxonomic group – qualify as potential invasive alien species. The authors did not attempt to estimate the true candidate pool or percentage of invasive species for insects. For vascular plants, the authors estimated the candidate pool at 47,000 species (out of a total of 368,000 species on Earth), or 13%.

Like its predecessor, this study’s importance arises from its broad perspective – covering the entire globe and a wide range of taxonomic groups. Its major conclusion that invasions will continue on a large scale serves as a warning to all stakeholders. These include officials charged with protecting agriculture and the broader economy, or the natural environment; conservationists; and those engaged in the economic activities that promote invasion.

However, the authors found that the data did not support more specific advice. First, as noted above, they were unable to determine which of the “emerging” invasive species in all taxonomic groups have a high potential to spread.

For those of us focused on invasive species that threaten native plants, data gaps limit the predictive value of the study the most. The database is too scant even to estimate the invasive species “pool” of potential insect pests. Plant pathogens are not included in the analysis.

Posted by Faith Campbell and Phyllis Windle

Act Now: Forest Protection in the 2018 Farm Bill

NOW is the time to advocate inclusion of important proposals in the 2018 Farm Bill. It is currently under consideration by the U.S. House of Representatives and Senate. If we miss this round of Farm Bill legislation, there won’t be another opportunity until 2023. Urge your Senators and Representative to support creation of the two grant-based funds described below.

What’s the issue?

We know that about 500 species of non-native insects and pathogens that attack native trees and shrubs are established in the United States. The number in Canada is 180 – there is considerable overlap.

Protecting the trees and their ecosystem services requires development and deployment of a set of tools aimed at either reducing the pests’ virulence or strengthening the tree hosts’ resistance or tolerance. Such strategies include biological control targetting the insect or pathogen and breeding trees resistant to the pest. Developing and employing these tools require sustained effort over years.

Unfortunately, the programs now charged with responding to introduced forest pests are only a ragged patchwork of university, state, and federal efforts. They provide neither the appropriate range of expertise nor continuity. (For a more thorough discussion of the resources needed to restore tree species badly depleted by non-native pests, read Chapter 6 of Fading Forests III, posted here.)

CISP-backed Amendments

In order to begin filling the gaps, the Center for Invasive Species has proposed forest-related legislation for the Farm Bill currently being considered by Congress.

We propose creation of two new funds, each to provide grants to support tree-protection and restoration projects. We find that the expertise and facilities needed to plant and maintain young trees in the forest differ enough from those needed to research and test biological approaches to pest management and tree improvement that each deserves its own support.

Our first proposal would create a grant program managed by the National Institute of Food and Agriculture (NIFA) to provide long-term funding for research to restore tree species severely damaged by alien pests. The focus of the research would be on:

Biocontrol of pests threatening native tree species;
Exploration of genetic manipulation of the pests;
Enhancement of host- resistance mechanisms for individual tree species;
Development of other strategies for restoration; and
Development and dissemination of tools and information based on the research.

Entities eligible for funding under our proposal would include:

Agencies of the U.S. government;
State cooperative institutions;
A university or college with a college of agriculture or wildlife and fisheries; and
Non-profit entities recognized under Section 501(c)(3) of the Internal Revenue Code.

Our second proposal would provide long-term funding to support research into and deployment of strategies for restoring pest-decimated tree species in the forest. The source of funds would be the McIntire-Stennis program. The eligible institutions would be similar: schools of forestry; land grant universities; state agricultural and forestry experimental stations; and non-profit non-governmental organizations. Projects would integrate the following components into a forest restoration strategy:

Collection and conservation of native tree genetic material;
Production of propagules of native trees in numbers large enough for landscape scale restoration;
Site preparation of former of native tree habitat;
Planting of native tree seedlings; and
Post-planting maintenance of native trees.

In addition, competitive grants issued by this second fund would be awarded based on the degree to which the grant application addresses the following criteria:

Risk posed to the forests of that state by non-native pests, as measured by such factors as the number of such pests present in the state;
The proportion of the state’s forest composed of species vulnerable to non-native pests present in the United States; and
The pests’ rate of spread via natural or human-assisted means.

(To request the texts of the proposed amendments, use the “contact us” button.)

A Growing Chorus Sees the Same Need

A growing chorus of scientists is calling for long-term funding for forest restoration programs based partly on recent scientific breakthroughs. So this year’s Farm Bill provides a key opportunity for initiating such programs.

The NIFA Letter

The National Institute of Food and Agriculture asks scientists each year to suggest their highest priorities for the agency’s research, extension, or education efforts. In December, twenty-eight scientists replied by calling for setting up a special “division” within NIFA to fund breeding of pest-resistant tree species and associated extension.

The lead authors are Pierluigi (Enrico) Bonello, Ohio State University, and Caterina Villari, University of Georgia. The 26 co-signers are scientists from 12 important research universities, along with the U.S. Forest Service (the Universities of Georgia, California (Berkeley), Florida, Kentucky, Minnesota, and West Virginia; Auburn University; Michigan Technological University; North Carolina State University; Oregon State University; Purdue University; the State University of New York).

The scientists note that recent scientific advances have created a new ability to exploit genetic resistance found in the tree species’ natural populations. They assert that developing and deploying host resistance promises to improve the efficacy of various control strategies – including biocontrol – and provides a foundation for restoring forest health in the face of ever-more non-native forest pests.

The scientists’ proposal differs from CISP’s in calling for establishment of research laboratories and field study sites at several locations in the country. These would be permanently funded to conduct screening and progeny trials, and adequately staffed with permanent cadres of forest tree geneticists and breeders who would collaborate closely with staff and university pathologists and entomologists. The apparent model is the USDA Forest Service’ Dorena Genetic Resource Center in Oregon. Dorena has had notable success with breeding Port-Orford cedar and several white pine species that are tolerant of the pathogens that threaten them.

POC trials at Dorena

In contrast, the CISP proposal relies largely on the chestnut model, which relies more on non-governmental organizations and wide-ranging collaboration. Our overall goal is similar, though: to provide stable funding for the decades-long programs needed to restore forest tree species.

American Chestnut Foundation chestnut growing in Northern Virginia

Why do we advocate grant programs instead of establishment of permanent facilities? We thought that Congress would be more likely to accept a smaller and cheaper set of grant programs in the beginning. Once the value of the long-term strategies is demonstrated more widely, supporters would have greater success in lobbying for creation of the permanent facilities.

Among the new technologies that would seem to justify the scientists’ assertion that success in breeding now appears to be more likely is the use of FT-IR and Raman spectroscopy and associated analysis of tree chemicals to identify individual trees within natural populations that have an apparent ability to tolerate disease-causing organisms. The leading scientist on the NIFA letter, Enrico Bonello, has used the technique to identify coast live oaks resistant to Phytopthora ramorum (the causal agent of sudden oak death. He is now testing whether the technique can identify Port-Orford cedar trees tolerant of the root-rot fungus Phytophthora lateralis and whitebark pines resistant to white pine blister rust.

I blogged about Enrico’s work on ash resistance to EAB here.) You can learn more about Enrico’s interesting work here.

The NAS Study

Meanwhile, the National Academies of Sciences, Engineering, and Medicine has launched a study on The Potential for Biotechnology to Address Forest Health. By the end of 2018, a committee of experts will report on the potential use of biotechnology to mitigate threats to forest tree health; identify the ecological, ethical, and social implications of deploying biotechnology in forests, and develop a research agenda to address knowledge gaps about its application. Funding for the study has been provided by The U.S. Endowment for Forestry and Communities; several agencies within the U.S. Department of Agriculture – Animal and Plant Health Inspection Service, U.S. Forest Service, National Institute of Food and Agriculture, Agricultural Research Service; and U.S. Environmental Protection Agency.

The Committee meetings are webcast, and there are other webinars on pertinent topics. You can view the schedule and sign up to receive alerts here.

Several people actively engaged in finding answers to invasive pest challenges have presented their views to the Committee, including Gary Lovett, Deb McCullough, Richard Sniezko, and me (!). You can find our presentations (Powerpoints and oral) at the above website. My talk focused on the crisis posed by non-native insects and pathogens and the need to evaluate the full range of possible response strategies for each host-pest situation. Application of genetic engineering technologies – in the absence of adequate resources for research and deployment of resistant hosts – cannot result in restoration of the host trees.

Background Information

Examples of tree-killing pests include such famous examples as chestnut blight and Dutch elm disease as well as less-well-known pests as soapberry borer. This map

indicates how many of the most damaging pests are established in each county of the 49 conterminous states. Descriptions of some of these insects and pathogens are provided here.

Additional tree-killing pests not included in the sources for the data supporting the map for various reasons would add to the numbers of pests in some states. Some non-native organisms have been introduced too recently, others attack palms or trees in Hawai`i; still others are native to Mexico and parts of the United States so were not included.

Posted by Faith Campbell

Bad News & Good News – current situation

American beech; FT Campbell

I recently attended USDA’s annual Interagency Research Forum on Invasive Species in Annapolis, MD, and have good and bad news to report about forest pests – mostly about insects but also a little on weeds.

Bad News

New pest: The European leaf-mining weevil is killing American beech in Nova Scotia. Jon Sweeney of Natural Resources Canada thinks it could spread throughout the tree species’ range. (I alerted you to another new pest of beech – beech leaf disease – at the beginning of December. Beech is already hard-hit by beech bark disease.)

New information added in June: according to Meurisse et al. (2018), the weevil overwinters under the bark of beech and trees that are not hosts, so it can be transported by movement of firewood and other forms of unprocessed logs and branches. [Meurisse, N. D. Rassaati, B.P. Hurley, E.G. Brockerhoff, R.A. Haack. 2018. Common Pathways by which NIS forest insects move internationally and domestically. Journal of Pest Science. https://doi.org/10.1007/s10340-018-0990-0]

Other bad news concerns the spread of already-established pests:

Hemlock woolly adelgid has been detected in Nova Scotia – where it has probably been present for years.
Emerald ash borer has been detected in Winnipeg, Manitoba – home to an estimated 350,000 ash trees. Winnipeg is 1,300 km (870 miles) from Saulte Ste. Marie, the closest Canadian outbreak. The closest U.S. outbreak is in Duluth, Minnesota — 378 miles.
Despite strenuous efforts by Pennsylvania (supported, but not adequately, by APHIS), (see my blog from last February ), spotted lanternfly has been detected in Delaware, New York, and Virginia. A map showing locations of apple orchards in the Winchester, Virginia area is available here.
There is continued lack of clarity about biology and impact of velvet longhorned beetle (see my blog from last February.) The Utah population appears to be growing. APHIS is funding efforts to develop trapping tools to monitor the species.
Alerted at the Forum, I investigated a disease on oak trees caused by the pathogen Diplodia corticola. Already recorded in Florida, California, Massachusetts and Maine, last year the disease was also detected in West Virginia. Forest pathologists Danielle Martin and Matt Kasson don’t expect this disease to cause widespread mortality. However, they do expect it to weaken oaks and increase their vulnerability to other threats.

spread of laurel wilt disease

Laurel wilt disease is one of the worst of the established non-native pests. Two speakers at the Forum described its ecological impacts.

Dr. John Riggins of the University of Mississippi reported that 24 native herbivorous insects are highly dependent on plants vulnerable to the laurel wilt insect-pathogen complex. One of these, the Palamedes swallowtail butterfly (Papilio palamedes) has suffered a three-fold to seven-fold decline in populations at study sites after the death of redbay caused by laurel wilt.

Dr. Frank Koch of the USDA Forest Service expects that the disease will spread throughout most of the range of another host, sassafras. (See a map of the plant’s range). With the climate changing, the insect is unlikely to suffer winter cold mortality in the heart of the tree’s range in Kentucky, West Virginia, and Virginia.

Apparently many birds depend on spicebush, a shrub in the Lauraceae family, but there is no easily available data on any changes to its distribution or health.

Good News

Other speakers at the Forum provided encouraging information.

Scientists described progress on breeding American elm trees resistant to or tolerant of the introduced Dutch elm disease (DED). USFS scientists led by James Slavicek and Kathleen Knight are trying to improve the genetic diversity and form of disease-tolerant American elms and to develop strategies for restoring them to the forest.

More than 70 seedlings planted in an orchard are being inoculated with the DED pathogen to test the trees’ tolerance. The project continues to collect seeds or cuttings from apparently resistant or tolerant trees. If you are aware of a large surviving elm in a natural setting (not urban planting), please contact the program via its website.

The project is also experimenting with methods for restoring trees in the forest. In one such experiment, elms, sycamores, and pin oaks have been planted at sites in Ohio where openings had been created by the death of ash attacked by emerald ash borer. Survival of the elm seedlings has been promising.

Also, there is cause to be optimistic re:

Walnut / thousand cankers disease

In the East, walnut trees appear to recover from thousand cankers disease. One factor, according to Matt Ginzel of Purdue University, is that the thousand canker disease fungus, Geosmithia morbida, is a weak annual canker that would not cause branch or tree mortality in the absence of mass attack by the walnut twig beetle. Another factor is the greater reliability of precipitation in the East. Dr. Ginzel is now studying whether mass attack by the beetle is sufficient – alone – to kill walnut trees.

b) Sirex noctilio

In Ontario, Laurel Haavik, U.S. Forest Service, finds both low impacts (so far) and evidence of resistance in some pine trees.

Also, scientists are making progress in developing tools for detecting and combatting highly damaging pests.

Richard Stouthammer of U.C. Riverside has detected an effective chemical attractant for use in monitoring polyphagous and Kuroshio shot hole borers. He is testing other pheromones that could improve the attractant’s efficacy. He has also detected some chemicals that apparently repel the beetles. His colleague, pathologist Akiv Eskalen, is testing endophytes that attack the beetles’ Fusarium fungus.
Several scientists are identifying improved techniques for surveillance trapping for wood-boring beetles. These include Jon Sweeney of Natural Resources Canada and Jeremy Allison of the Great Lakes Forestry Centre.

Progress has also been made in biocontrol programs targetting non-native forest pests.

Winter moth

Joseph Elkington of the University of Massachusetts reports success following 12 years of releases of the Cyzenis moth – a classical biocontrol agent that co-evolved with the winter moth in Europe. The picture is complex since the moths are eaten by native species of insects and small mammals and parasitized by a native wasp. However, native predators didn’t control the winter moth when it first entered Massachusetts.

2) Emerald ash borer

Jian Duan of the Agriculture Research Service reported that biocontrol agents targeting the are having an impact on beetle densities in Michigan, where several parasitoids were released in 2007 to 2010. The larval parasitoid Tetrasrticus planipennisi appears to be having the greatest impact. A survey of ash saplings at these sites in 2015 found that more than 70% lacked fresh EAB galleries. In other trees, larval density was very low – a level of attack that Duan thinks the trees can survive.

However, Tetrasrticus has a short ovipositor so it is unlikely to be able to reach EAB larvae in larger trees with thicker bark. Furthermore, most of the biocontrol agents were collected at about 40^o North latitude. It is unclear whether they will be as successful in controlling EAB outbreaks farther South.

Consequently, Duan noted the need to expand the rearing and release of a second, larger braconid wasp Spathius galinae, continue exploration in the southern and western edges of the EAB native range for new parasitoids; and continue work to determine the role of the egg parasitoids.

A brochure describing the U.S. EAB biocontrol program is available here

Canada began its EAB biocontrol program in 2013, using parasitoids raised by USDA APHIS. While evaluating the efficacy of these releases, Canada is also testing whether biocontrol can protect street trees.

3) Hemlock woolly adelgid

Scientists have been searching for a suite of biocontrol agents to control HWA for 25 years. Scientists believe that they need two sets of agents – those that will feed on the adelgid during spring/summer and those that will feed on HWA during winter/spring.

The first agent, Sasajiscymnus tsugae, was released in large numbers beginning in 1995. It is easy to rear. However, there are questions regarding its establishment and impact.

Laricobius nigrinus – a winter/spring feeder from the Pacific Northwest – was released beginning in 2003. It is widely established, especially in warmer areas. A related beetle, L. osakensis, was discovered in a part of Japan where eastern North American populations of HWA originated. Releases started in 2012. Scientists are hopeful that this beetle will prove more effective than some of the other biocontrol agents.

Winter cold snaps in the Northeast have killed HWA. While HWA populations often rebound quickly, predatory insects might suffer longer-term mortality. This risk intensifies the importance of finding agents that attack HWA during the spring or summer. Two new agents – the silver flies Leucopis artenticollis and L. piniperda – may be able to fill this niche. Both are from the Pacific Northwest. Initial releases have established populations.

4) USDA scientists are at earlier stages of actively seeking and testing possible biocontrol agents targetting Asian longhorned beetle and spotted lanternfly.

5) Invasive Plant Management

A study in New York City shows that invasive plant removal can have lasting effects. Lea Johnson of the University of Maryland studied vegetation dynamics in urban forest patches in New York City. Her publications are available here.

In the 1980s New York undertook large scale restoration of its parks, including removal of invasive plants – especially multiflora rose, porcelainberry (Ampelopsis) and oriental bittersweet (Celastris). The goal was to establish self-sustaining forest with regeneration of native species. In 2006, Dr. Johnson was asked to evaluate the parks’ vegetation. She compared restored sites and similar sites without restoration.

I find it promising that Dr. Johnson found persistent differences in forest structure and composition as much as 15 or 20 years after restoration was undertaken. Treated sites had significantly lower invasive species abundance, a more complex forest structure, and greater native tree recruitment.

Still, shade intolerant species were abundant on all sites. The native shade tolerant species that had been planted did not do as well because gaps in the canopy persist.

CONCLUSIONS

As always, the annual Interagency Research Forum on Invasive Species provides an excellent opportunity to get an overview of non-native pest threats to America’s forests and the ever-wider range of scientists’ efforts to combat those threats. Presenters from universities as well as USDA, Canadian, and state agencies describe the status of host tree and pest species, advance promising technologies for detection, monitoring and control, and – increasingly – strategies for predicting potential pests’ likely impact. The networking opportunities are unparalleled.

Posted by Faith Campbell

You Might Be Surprised By Who is Authorized to Manage Wildlife on Federal Lands

mountain goats – introduced onto USFS-managed lands in the Columbia River Gorge at state initiative; in Utah, the state introduced mountain goats on lands adjacent to a USFS Research Natural Area

The journal Environmental Law has just published a 135-page article that debunks a common myth of wildlife management – a piece that the U.S. Forest Service tried to quash. The authors’ analysis could affect the introduction of potentially invasive non-native species – and the reintroduction of native ones – on federal lands.

Nie, M., C. Barns, J. Haber, J. Joly, K. Pitt & S. Zellmer. 2017. Fish and Wildlife Management on Federal Lands; debunking state supremacy. Environmental Law, Vol. 47, no. 4 (2017).

The article reviews the legal authority of federal and state governments to manage wildlife on federal lands. The authors examined wildlife-related provisions within the National Park System, National Wildlife Refuge System, National Forest System, Bureau of Land Management, the special case of Alaska, the National Wilderness Preservation System, and the Endangered Species Act. They also reviewed cases where federal and state agencies came into conflict over wildlife management on federal lands.

Citing the U.S. Constitution, federal land laws, and relevant case law, the authors assert that federal agencies have an obligation, not just the discretion, to manage and conserve fish and wildlife on lands and waters under their management. They say that the often-cited statement that “the states manage wildlife and federal land agencies only manage wildlife habitat” is wrong from a legal standpoint. This is the myth that the article debunks.

Furthermore, the authors find that federal agencies frequently apply their powers in an inconsistent and sometimes even unlawful fashion. Due to political pressures, they may back down when confronted by states wanting to manage wildlife to achieve their own goals – even when the state’s goals conflict with the legally-mandated purposes of the federal land under question. Such goals might include ensuring maximum populations of “game” animals or introduction of species to new habitats – regardless of the potential impact on native plants and animals.

The authors note that federal land and wildlife laws provide ample opportunities for constructive intergovernmental cooperation in wildlife management. They call for truly mutual collaboration by federal, state, and tribal authorities in managing wildlife. However, such cooperation is blocked in part by states choosing to challenge the constitutional powers, federal land laws, and U.S. government supremacy. In addition, the authors contend, most states have not put together programs that address their own conservation obligations. These obligations are inherent in the widely recognized doctrine of wildlife being a public trust to be managed for the present and future benefit of the people, not the government or private individuals.

According to the website of the Forest Service Employees for Environmental Ethics, posting of a draft of this article on the University of Montana website (where lead author Martin Nie teaches) led the U.S. Forest Service to pressure the university to withdraw the article. The university refused, and the Forest Service ended its contract with Nie and his research center.

The paper can be downloaded here. 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.

Posted by Faith Campbell

New Disease that Attacks Beech is Spreading

beech leaf disease symptoms; photo by John Pogacnik, Lake Metroparks

In 2012, Ohio authorities detected a new disease attacking American beech (Fagus grandifolia) in northeast Ohio. The disease has spread to several counties in northeast Ohio and neighboring areas of Pennsylvania, New York, and Ontario.

Counties currently reporting beech leaf disease; Cleveland Plain Dealer relying on data from Ohio Department of Natural Resources

Currently, no cause has been determined – despite efforts by the USDA Forest service, Ohio Division of Forestry, Ohio Department of Agriculture, Holden Arboretum, and Ohio State University.

Early symptoms are dark striping on the leaves – best seen by looking upward into the backlit canopy. The striping is formed by a darkening and thickening of leaf tissue between leaf veins. Later, lighter, chlorotic striping may also occur. Both fully mature and very young “emerging” leaves show symptoms. Eventually the affected foliage withers, dries, and yellows. Bud and leaf production is also affected. However, there is little premature leaf loss.

All ages and sizes of beech are affected. Sapling and pole-sized trees die within about three years after symptoms are observed. In areas where the disease is established, the proportion of American beech affected nears 100%.

Disease incidence does not appear to be influenced by slope, aspect, or soil conditions. Also, while a wide variety of insects and pathogens is associated with symptomatic trees, these appear to be separate from and unrelated to beech leaf disease.

The disease might also affect European and Asian beech.

Given the range and ecological importance of American beech – a species already under threat in from beech bark disease – scientists seek to form a collaborative group that would efficiently address research issues related to the cause of this malady and management implications for the species.

Beech trees in the Northeast, Appalachians, and even Michigan are already under threat from beech bark disease, described here .

Workshop to Coordinate Research and Management

A workshop will take place May 2-3, 2018 at Cleveland Metroparks Watershed Stewardship Center, 2277 West Ridgewood Drive, Parma, OH 44134

https://clevelandmetroparks.com/parks/visit/parks/west-creek-reservation/watershed-stewardship-center-at-west-creek

Presentations on the first day of the meeting would seek to

Prioritize next steps and coordinate efforts.
Increase communication and coordination among land managers and researchers.
Inform resource allocation and leverage funding sources for maximum effectiveness.
Set up 5-year plan – Research, Survey, Diagnostics, etc.

The second day would include a field trip to view the disease.

Contact one of the following if you are interested in giving a presentation on the ecological importance of beech; or the history, etiology, surveys, or epidemiology of beech leaf disease.

James Jacobs (jamesjjacobs@fs.fed.us)
Connie Hausman (ceh@clevelandmetroparks.com)
Danielle Martin (dkmartin@fs.fed.us)
John Pogacnik (jpogacnik@lakemetroparks.com)

healthy beech in Virginia; F.T. Campbell

SOURCES

http://portal.treebuzz.com/beech-tree-leaf-disease-no-known-cause-1036

John Pogacnik, Biologist, Lake Metroparks & Tom Macy, Forest Health Program Administrator, Ohio Department of Natural Resources Division of Forestry. Forest Health Pest Alert Beech Leaf Disease July 2016