Category: funding

Progress – Now Threatened – On Protecting Our Cacti

prickly pear cacti in Big Bend National Park
photo by Blake Trester, National Park Service

The cacti that are such important components of desert ecosystems across nearly 2 million square miles straddling the U.S.-Mexico border are under threat from non-native insects – as I have noted in earlier blogs. Of course, cacti are important in other ecoregions, too – I wrote recently about the columnar cacti in the dry forests of Puerto Rico.

Flat-padded prickly pear cacti of the genus Opuntia are threatened by the cactus moth, Cactoblastis cactorum.

In 1989, the cactus moth was found in southern Florida, to which it had spread from the Caribbean islands (Simonson 2005). Recently, the moth was found to have spread west as far as the Galveston, Texas, area and near I-10 in Columbus, Texas, about 75 miles west of central Houston (Stephen Hight, pers. com.) Two small outbreaks on islands off Mexico’s Caribbean coast have been eradicated.

In Florida, the cactus moth has caused considerable harm to six native species of prickly pear, three of which are listed by the state as threatened or endangered.

When the cactus moth reaches the more arid regions of Texas, it is likely to spread throughout the desert Southwest and into Mexico. In the American southwest, 31 Opuntia species are at risk; nine of them are endemic, one is endangered. Mexico is the center of endemism for the Opuntia genus. In Mexico, 54 Opuntia species are at risk, 38 of which are endemic (Varone et al. 2019; full citation at end of this blog).

The long-term effects of the cactus moth on these North American Opuntia are unknown because there may be substantial variations in tolerance. The attacks observed in the Caribbean islands have shown great variability in various cactus species’ vulnerability (Varone et al. 2019).

The Opuntia cacti support a diversity of pollinators as well as deer, javalina (peccaries), tortoises, and lizards. Prickly pears also shelter packrats and nesting birds (which in turn are fed on by raptors, coyotes, and snakes), and plant seedlings. Their roots hold highly erodible soils in place (Simonson 2005).

While scientists have been concerned about the possible impacts of the cactus moth since it was detected in Florida 30 years ago, a substantial response began only 15 years later. The U.S. Department of Agriculture began trying to slow the spread of the cactus moth in 2005 (Mengoni Goñalons et al. 2014), with a focus on surveys and monitoring, host (cactus) removal, and release of sterile males. This program was successful at slowing the moth’s spread and eradicating small outbreaks on offshore islands of Alabama, Mississippi, and Mexico.

Cactus moth damage to native cacti in Florida
photo by Christine Miller, UF/IFAS

However, the moth continued to spread west and the program never received an appropriation from Congress. The primary funding source was a US – Mexico Bi-National Invasive Cactus Moth Abatement Program. Both countries contributed funds to support the research and operational program to slow the spread in the U.S. Funds were provided through USDA Animal and Plant Health and Inspection Service (APHIS) and the Mexican Secretariat of Agriculture, Livestock, Rural Development, Fisheries and Food (SEGARPA). Unfortunately, funding was reduced by both entities and became inadequate to maintain the Bi-National Program.

Therefore, in 2012, APHIS abandoned its regional program and shifted the focus to biocontrol. This is now considered the only viable control measure in the desert Southwest where vulnerable cacti are numerous and grow close together. The biocontrol project has been funded since 2012 through the Plant Pest and Disease Management and Disaster Prevention program (which receives funding through the Farm Bill). It has received a total of slightly more than $2 million over seven years. More than half the funds went to the quarantine facility to support efforts to rear non-target hosts and verify the biocontrol agent’s host specificity. About a quarter of the funds supported complementary work of an Argentine team (both the cactus moth and the most promising biocontrol agent are native to Argentina). Much smaller amounts have supported U.S.-based scientists who have studied other aspects of the cactus moth’s behavior and collected and identified the U.S. moths being tested for their possible vulnerability to attack by a biocontrol wasp.

Here are details of what these dedicated scientists achieved in just the past seven years at the relatively low cost of roughly $2 million. Unfortunately, the project now faces a funding crisis and we need to ensure they have the resources to finish their work.

Some Specifics of the BioControl Program

After literature reviews, extensive collections, and studies in the cactus moth’s native habitat in Argentina (Varone et al. 2015), a newly described wasp, Apanteles opuntiarum (Mengoni Goñalons et al. 2014), has been determined to be host specific on Argentine Cactoblastis species and the most promising candidate for biocontrol. Wasps were collected in Argentina and sent to establish a colony in a quarantine facility in Florida to enable host specificity studies on North American Lepidoptera (Varone et al. 2015).

Quarantine host specificity studies and development of rearing technology has not been straightforward. Initially, it was difficult to achieve a balanced male/female ratio in the laboratory-bred generations; this balance is required to maintain stable quarantine laboratory colonies for host range testing. This difficulty was overcome. A second challenge was high mortality of the cactus-feeding insects collected in the Southwest that were to be test for vulnerability to the biocontrol wasp. These desert-dwellers don’t do well in the humid, air-conditioned climate of the quarantine facility! For these difficult-to-rear native insects, scientists developed a molecular genetics method to detect whether eggs or larvae of the cactus moth parasitoid were present inside test caterpillars after they were exposed to the wasps. For easy to rear test insects, caterpillars are exposed to the wasps and reared to adulthood. Host specificity tests have been conducted on at least five species of native U.S. cactus-feeding caterpillars and 11 species of non-cactus-feeding caterpillars (Srivastava  et al. 2019; Hight pers.comm.).

To date there has been no instance of parasitism by Apanteles opuntiarum on either lepidopteran non-target species or non-cactus-feeding insects in the Florida quarantine or in field collections in Argentina (Srivastava et al. 2019; Varone et al. 2015; Hight pers.comm.).

The scientists expected to complete host-specificity testing in the coming months, then submit a petition to APHIS requesting the release of the wasp as a biocontrol agent. Unfortunately, the project’s request for about $250,000 in the current year was not funded. This money would have funded completion of the host specificity testing, preparation of a petition to APHIS in support of release of the biocontrol agent into the environment, and preparation of the release plan.

Meanwhile, what can we expect regarding the probable efficacy of the anticipated biocontrol program?

Some of the wasp’s behavioral traits are encouraging. The wasp is widely present in the range of the cactus moth, and persisted in these areas over the years of the study. The wasp can deposit multiple eggs with each “sting”. Multiple wasps can oviposit into each cactus moth without detriment to the wasp offspring. Unmated wasp females produce male offspring only, whereas mated females produce mixed offspring genders. In the field, female wasps attack cactus moth larvae in a variety of scenarios: they wait at plant access holes to sting larvae when they come outside to defecate; they attack larvae when they are moving on the surface of the pads; they can sting the youngest cactus moth larvae through the thin plant wall of mined the pads; and they enter large access holes created by older larvae and attack larger larvae. The wasps are attracted by the frass (excrement) left on the outside of the cactus pads by cactus moth larvae (Varone et al. 2020).

However, I wonder about the extent to which the cactus moth is controlled by parasitoids in Argentina. Cactoblastis eggs are killed primarily by being dislodged during weather events (rain and wind) and by predation by ants. First instar larvae are killed primarily by the native Argentine cactus plants’ own defenses – thick cuticles and release of sticky mucilage when the young larvae chew holes into the pads where they enter and feed internally. As larvae feed and develop inside the pads, the primary cause of mortality is natural enemies.

Of all the parasitoid species that attack C. cactorum, A. opuntiarum is the most abundant and important. When the larvae reach their final state (6th instars), they leave the pads and find pupation sites in plant litter near the base of the plants. It is at this stage that the parasitism from A. opuntiarum is detected in the younger larvae that were attacked while feeding inside pads. As the moth larva begins to spin silk into which to pupate, larvae of the wasp erupt through the skin of the caterpillar and pupate within the silk spun by the moth. Predation by generalists (ants, spiders, predatory beetles) accounted for high mortality of the unprotected last instar and pupae (Varone et al. 2019).

Finally, the cactus moth has three generations per year when feeding on O. stricta in the subtropical and tropical coastal areas of the Americas and the Caribbean. In Argentina, on its native host, the moth completes only two generations per year (Varone et al. 2019).

 How to Get the Program Support Needed

Opuntia in Big Bend National Park
Photo by Cookie Ballou,
National Park Service

To date, no organized constituency has advocated for protection of our cacti from non-native insect pests. Perhaps now that the Cactoblastis moth is in Texas, the threat it represents to our desert ecosystems will become real to conservationists and they will join the struggle. The first step is to resolve the funding crisis so that the agencies can complete testing of the biocontrol agent and gain approval for its release. So now there is “something people can do” – and I hope they will step forward.

I hope Americans are not actually indifferent to the threat that many cacti in our deserts will be killed by non-native insects. Many are key components of the ecosystems within premier National Parks, and other protected areas. Cacti also are beautiful treasures in botanical gardens. I hope conservationists will agree that these threats must be countered, and will help to ensure funding of the final stages of the biocontrol tests.

Sources

Mengoni Goñalons, C., L. Varone, G. Logarzo, M. Guala, M. Rodriguero, S.D. Hight, and J.E. Carpenter. 2014. Geographical range & lab studies on Apanteles opuntiarum (hymenoptera: braconiDae) in AR, a candidate for BC of Cactoblastis cactorum (Lepidoptera: Pyralidae) in North America. Florida Entomologist 97(4) December 2014

Simonson, S.E., T. J. Stohlgren, L. Tyler, W. Gregg, R. Muir, and L. Garrett. 2005. Preliminary assessment of the potential impacts and risks of the invasive cactus moth, Cactoblastis cactorum Berg, in the U.S. and Mexico. Final Report to the International Atomic Energy Agency, April 25, 2005 © IAEA 2005

Srivastava, M., P. Srivastava,  R. Karan, A. Jeyaprakash, L. Whilby, E. Rohrig, A.C. Howe,  S.D. Hight, and L. Varone. 2019. Molecular detection method developed to track the koinobiont larval parasitoid Apanteles opuntiarum (Hymenoptera: Braconidae) imported from Argentina to control Cactoblastis cactorum (Lepidoptera: Pyralidae). Florida Entomologist 102(2): 329-335.

Varone, L., C.M. Goñalons, A.C. Faltlhauser, M.E. Guala, D. Wolaver, M. Srivastava, and S.D. Hight. 2020. Effect of rearing Cactoblastis cactorum on an artificial diet on the behavior of Apanteles opuntiarum. Applied Entomology DOI: 10.1111/jen.12731.

Varone, L., G. Logarzo, J.J. Martínez, F. Navarro, J.E. Carpenter, and S.D. Hight. 2015. Field host range of Apanteles opuntiarum (Hymenoptera: Braconidae) in Argentina, a potential biocontrol agent of Cactoblastis cactorum (Lepidoptera: Pyralidae) in North America. Florida Entomologist — Volume 98, No. 2 803

Varone, L., M.B. Aguirre, E. Lobos, D. Ruiz Pérez, S.D. Hight, F. Palottini, M. Guala, G.A. Logarzo. 2019. Causes of mortality at different stages of Cactoblastis cactorum in the native range. BioControl (2019) 64:249–261

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.

2021 Funding: Crisis for USFS, OK for APHIS – Both Need Your Support

As happens every year, the Administration has proposed a budget for funding government programs in the next Fiscal Year (FY) – which begins on October 1, 2020 (FY2021). This proposal is not the final word. Congress will pass appropriations bills that will specify actual funding levels. NOW is the time for you to tell senators and representatives in Congress how much money you think agencies need to count tree-killing pests next year.

Pest programs most affected:

  • Sudden oak death (SOD):
  • Combination of goldspotted oak borer, laurel wilt, and thousand cankers disease
  • Port-Orford cedar root disease
  • Threats to whitebark pines
  • emerald ash borer

USDA Forest Service (USFS)

For the USFS, the Administration proposes alarming cuts.

Forest and Rangeland Research Program

FY18                           F719                FY20               FY21 proposed

297,000,000                300,000,000    305,000,000    249,330,000

[In FYs 18 – 20, Forest Inventory & Analysis received $77 million of this total; the proposal for FY21 is $78.5 million. Under this proposal, inventory would receive more than 30% of all research funding!]

The Administration proposes to cut USFS R&D overall by 25%. Also, it calls for closing the Pacific Southwest Research Station in California.

These proposed cuts would come on top of severe reductions over the past decade. Although the appropriation does not provide specific spending figures for invasive species, funding for research conducted by the seven research stations on ten non-native pests decreased from $10 million in FY2010 to just $2.5 million in FY2020 – a cut of more than 70%. The Service’s ability to develop effective tools to manage the growing number of pests threatening the health of the Nation’s forests is already crippled by the earlier cuts.

The proposal to close the Pacific Southwest Research Station is particularly unwise. This Station provides USFS’s crucially important expertise on both sudden oak death (SOD) and threats to Hawaiian forests, including rapid ʻōhiʻa death (ROD). These pathogens are already causing widespread and severe damage to forests in the region and leading experts work here.

USFS R&D must address two new threats associated with sudden oak death:

  1. need to better understand the possible impacts of the second, apparently more aggressive, genetic strain of the SOD pathogen now present in Oregon’s forests.
  2. studies to determine which of the newly detected Phytophthora species found in Southeast Asia Link to blog and other regions might cause significant damage to America’s trees.  

Other programs that USFS R&D should continue or expand:

  • study the possible threat posed by the ambrosia beetle recently detected in Napa Valley of California.
  • understand the epidemiology and probable impacts of the recently detected beech leaf disease present from Ohio to Connecticut and possibly more widespread.

Forest Health Management Programs 

Recent funding levels:

FY18                           F719                            FY20               FY21 proposed

96,500,000                  98,000,000                  100,000,000    73,636,000

The Forest Health Management (FHP) Program supports federal agencies’ and partners’ efforts to prevent, monitor, suppress, and eradicate insects, diseases, and invasive plants. The White House proposes a $23 million cut, including a cut of $10 million to programs working on “cooperative lands” – all areas other than federal lands. This proposed cut is short-sighted and worrisome. First, these forests support a wide range of forest values. Second, non-native pests usually are usually first introduced in cities or suburbs – because they accompany imports destined for population centers. These newly arrived pests initially cause enormous damage to urban forests. Counter-measures need to be initiated where and when the pests arrive and their populations are low. We cannot afford to wait for them to spread to national forest lands, when management will be harder and more expensive.

Despite ever-rising numbers of non-native forest pests over the past decade, funding for FHP work on Cooperative Lands has fallen by about 50%. Pest species suffering the largest cuts in recent FHP budgets are the combination of gold spotted oak borer, thousand cankers disease, and laurel wilt; Port-Orford cedar root disease, and threats to whitebark pines.

As I reported in a previous blog, an estimated 41% of forest biomass in the “lower 48” states is at risk from the 15 non-native pest species causing the greatest damage. Nevertheless, the Administration proposes to eliminate programs for several of the most hard-hit host tree species (redbay/laurel wilt, Port-Orford cedar, and whitebark pine) in FY2021. This proposal is contrary to priorities recommended through the CAPTURE project, which called for enhanced conservation efforts targetting these species specifically.

Also alarming is the cut to the informal “emerging pest” account. This valuable program funds projects targetting newly detected threats. Thus, in FY2019, FHP provided $125,000 to evaluate the probable impact of laurel wilt disease on sassafras, an important understory tree that grows throughout most of the Eastern Deciduous Forest. The program provided another $116,000 to support efforts to detect and understand beech leaf disease. Already, cuts in the overall FHP budget have necessitated cutting this valuable account  from $1 million in FY19 to $750,000 in FY20 – and will probably result in additional cuts  in FY21.

The budget proposes to cut funding to counter sudden oak death (SOD) Link to DMF by 15% — on top of a 52% cut since FY2018. SOD has killed an estimated 50 million trees from southern Oregon to central California. Not only does the pathogen continue to spread. Establishment of a second, more aggressive, genetic strain of the pathogen in the Oregon forest threatens to exacerbate the pathogen’s impact.

The forests of Hawai`i are facing their gravest threat ever from a growing number of pests. FHP supported detection/monitoring of the thrips attacking a dry forest tree, naio. There is a continuing need to address threats to Hawaii’s most widespread tree, ʻōhiʻa lehua – which makes up 80% of  native forests –  from the introduced “rapid ʻōhiʻa death” fungi.

Finally, stakeholders will depend on leadership by the FHP program to manage spread of the emerald ash borer if the USDA Animal and Plant Health Inspection Service acts as expected and terminates the program under which it regulates movement of firewood, nursery stock, and other items that spread this pest. California and Oregon and other Western states are at greatest risk.

What You Can Do

Senators and representatives serving on the two Interior Appropriations subcommittees will determine the final funding for USFS programs.  

Please ask them to support $303 million for USFS Research and Development. Since the budget does not specify funding levels to be allocated to non-native insects, pathogens, or other invasive species, ask for “report language” instructing USFS to increase the funding for this vital research area to five percent of the total research budget. Ask them also to support maintaining the Pacific Southwest Research Station.

Also, ask them to support maintaining USFS Forest Health and Management Programs at the FY20 level of $100 million in FY21. Ask them to support $44 million for the “cooperative lands” program.

Members of the House Interior Appropriations subcommittee

  • Betty McCollum, Chair                        MN
  • Chellie Pingree                         ME
  • Derek Kilmer                           WA
  • José Serrano                            NY
  • Mike Quigley                           IL
  • Bonnie Watson Coleman         NJ
  • Brenda Lawrence                     MI
  •  
  • David Joyce, Ranking Member            OH
  • Mike Simpson                          ID
  • Chris Stewart                           UT
  • Mark Amodei                          NV

Members of the Senate Interior Appropriations subcommittee

USDA Animal and Plant Health Inspection Service (APHIS)

Again, while the tree-killing pests are usually introduced first in cities or suburbs, the pests don’t stay there. Instead, they proliferate and spread … eventually threatening forests across the continent.  

APHIS has legal responsibility for preventing such pests’ entry, detecting newly introduced pests, and initiating eradication and containment programs intended to minimize the damage they cause. The risk of new introductions is tied to international trade. In 2017, an estimated 17,650 shipping containers (or 48 per day) infested by wood-boring insects entered the United States. Examples of such introductions include the Asian longhorned beetle, emerald ash borer, and several ambrosia beetles which carry the fungi now killing redbay and sassafras in the East, and sycamore and willow trees southern California. Other pests, such as gypsy moths and spotted lanternflies, are transported here as egg masses attached to hard-sided imports, containers, or ship superstructures. Yet more forest pests are brought here with or in imported plants. Two rapid ʻōhiʻa death (ROD) pathogens and beech leaf disease are among newly detected pests probably introduced this way.

APHIS needs to be able to respond to these pests and to the others that will be introduced in coming years. To do so, APHIS must have adequate funding for four programs: “tree and wood pests” program at $60 million; “specialty crops” program at $192 millon; “methods development” at $28 million; and “detection” at $21 million.

The “Tree and Wood Pests” account currently supports eradication and control efforts targeting only three insects: the Asian longhorned beetle (ALB), emerald ash borer (EAB), and gypsy moth. The program to eradicate the ALB has received about two-thirds of the funds — $40 million. It has succeeded in eradicating 85% of the infestation in New York and some of the outlying infestations in Ohio. There is encouraging progress in Massachusetts, although at least one infested tree was detected recently in a new town within the quarantine zone. Clearly, this program must be maintained until final success is achieved everywhere.

The EAB program has been funded at $7 million in recent years. APHIS has proposed to terminate the EAB regulatory program. Program termination would greatly increase the risk that the EAB will spread to the mountain and Pacific coast states, where both riparian woodlands and urban forests would be severely damaged. Many stakeholders have urged APHIS to continue to regulate movement of firewood and other materials that facilitate the EAB’s spread.

The “Specialty Crops” program funds for APHIS’ regulation of nursery operations to prevent spread of the sudden oak death pathogen. Were SOD to become established in the East, it would threaten several oak species, sugar maple, and black walnut. It is therefore alarming that in 2019, plants infected by the SOD pathogen were shipped to 18 states. link to blog APHIS must step up its regulatory efforts to prevent a repetition of this disaster.

What You Can Do

Members of the Senate and House Agriculture Appropriations Subcommittees will set  final funding levels for APHIS programs. Ask your members of Congressto support maintaining the FY2020 funding levels for four APHIS programs: Tree and Wood Pests, Specialty Crops, Methods Development, and “Detection Funding”.

Also, ask them to adopt report language urging APHIS to continue regulating the EAB’s spread. 

Members of the House Agriculture Appropriations subcommittee

  • Sanford Bishop Jr., Chairman              GA
  • Rosa DeLauro                                      CT
  • Chellie Pingree                                     ME
  • Mark Pocan                                         WI
  • Barbara Lee                                         Calif 13th (Oakland)
  • Betty McCollum                                  MN
  • Henry Cuellar                                      TX
  •  
  • Jeff Fortenberry, Ranking Member      NE
  • Robert Aderholt                                               AL
  • Andy Harris                                         MD
  • John Moolenaar                                               MI

Members of the Senate Agriculture Appropriations subcommittee

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.

Congressional Funding for Key USDA Programs

Fiscal Year 2020 began on October 1, 2019. In December Congress adopted funding bills (appropriations) for the full fiscal year – which ends next September.

APHIS

In its Agriculture Appropriations bill, Congress is holding steady or increasing funding for several APHIS programs that are important for addressing tree-killing pests:

  • tree and wood pests program – $60 million (this is the same as FY2019, and $4 million above the Administration’s request);
  • Pest Detection – $27.4 million (this is same as FY219 and as the Administration’s request);
  •  Methods development – $20.686 million (about the same as in FY2019 and the Administration’s request).
  • Specialty crops program – increased to $192.013 million. The accompanying report mentions two specific organisms as priorities – navel orangeworm and sudden oak death (apparently in response to an Oregon economic study and because Sen. Merkley is on the Appropriations Committee).  This was above the $186 million in both the House and Senate bills and considerably above the Administration’s request of $176 million.

The Agriculture Appropriations bill reiterates helpful language from past laws authorizing the Secretary of Agriculture “to transfer … funds available to … the Department [of Agriculture] such sums as may be deemed necessary” to respond to disease or pest emergencies that threaten any segment of the U.S. agricultural production industry. However, for the past decade the Office of Management and Budget has prevented frequent use of this power. APHIS did receive emergency funds to address the spotted lanternfly in February 2018 (APHIS Press Release No. 0031.18)

(You might remember that in 2017-2018 I put forward amendments to the Farm Bill that would have broadened APHIS’ access to emergency funds. I sought especially to ensure that efforts to protect native vegetation and urban trees would be eligible for funding. Unfortunately, this amendment was not enacted.)

USDA Forest Service

The overall Research and Development program is funded at $305 million – a few million above what I advocated for.  Of this total, $77 million is allocated to the Forest Inventory and Analysis program. In the past, research on invasive species has received about 10% of the total research funds. The USFS has been directed by Congress to restructure its research program. I will monitor any changes and determine the implications for invasive species concerns.

USFS engagement on pest issues with other federal agencies and state, local government, and private land managers is carried out through the Forest Health Management program under the State and Private Forestry division. While neither the appropriations legislation nor the accompanying report provides any direction on forest health activities, program staff report that funding for the overall program totals $104 million – about $6 million more than in FY2019. Program work on federal lands is funded at $66 million. However, $3 million has been deducted as part of a budget reform. After the deduction, this allocation is about $7 million above the funding level for FY 2019. Program work on non-federal “cooperative” lands is funded at $44 million. Congress has instructed that $2 million of this total be given to the eastern states’ forest health monitoring cooperative. The total “cooperative” lands allocation is $2 million above the FY2019 allocation.

Conclusion

I am very pleased by Congress maintaining or increasing funds for APHIS’ forestry programs. I am somewhat concerned by the pressure to reform USFS programs. I worry especially about the increasing focus on managing pests on federal lands compared to non-federal lands because nearly all damaging invasions begin on non-federal lands.

ash tree killed by emerald ash borer
Ann Arbor, MI
photo provided courtesy of former mayor John Hieftje

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.

NPS Report Published in Journal – Has it Been Implemented? Can it Be?

invasive lake trout in Yellowstone National Park

The National Park Service has a legal mandate to manage lands and waters under its jurisdiction so as to “preserve unimpaired” their natural and cultural resources (NPS Organic Act 54 U.S.C. § 100101, et seq.) Invasive species undermine efforts to achieve that mission. In 2000, the NPS adopted a program to coordinate management of invasive plants. It’s not as effective as needed – see the strategic plan.  

However, only recently has NPS begun trying to prioritize and coordinate programs targetting the many animals and animal diseases which threaten Park resources. These organisms range from emerald ash borer and quagga mussels; to pythons, goats, and pigs; to diseases such as white nose syndrome of bats and avian malaria in Hawai`i.

In 2017, NPS released an internal study of the pervasive threat to Park resources posed by invasive animals and discussed steps to overcome barriers to more effective responses (Redford et al., 2017; full citation at end of this blog). The Chief of the Biological Resources Division initiated this report by asking a Science Panel to evaluate the extent of the invasive animal problem, assess management needs, review best practices, and assess potential models that could serve as a service-wide organizational framework. The report was to pay particular attention to innovative and creative approaches including, but not limited to, new genomic tools. I summarized the Panel’s  findings and conclusions in a blog when its report appeared in 2017.

Significantly, the Panel’s final report states that “a general record of failure to control invasive species across the system” was caused principally by a lack of support for invasive species programs from NPS leadership.

This report has now appeared in the form of a peer-reviewed article in the journal Biological Invasions by Dayer et al. 2019 (full citation at end of this blog). Although nine of the ten authors are the same on both reports there are substantive differences in content. For example, the journal article reiterates the principal findings and conclusions of the Panel’s final report, but in less blunt language.

What’s Been Watered Down

The toning down is seen clearly in the statements some of the panel’s six key findings.

Finding #1

            The panel’s report says:  invasive animals pose a significant threat to the cultural and natural values and the infrastructure of U.S. national parks. To date, the NPS has not effectively addressed the threat they pose.

            Dayer et al. says: the ubiquitous presence of invasive animals in parks undermines the NPS mission.

Finding #2

            The panel’s report says: managing invasive animals will require action starting at the highest levels, engaging all levels of NPS management, and will require changes in NPS culture and capacity.

            Dayer et al. says: coordinated action is required to meet the challenge.

Finding #4

            The panel’s report states: effective management of invasive animals will require stakeholder engagement, education, and behavior change.

            Dayer et al. says: public engagement, cooperation and support is [sic] critical.

Wording of the other three “key findings” was also changed, but these changes are less substantive.

Drayer et al. also avoid the word “failure” in describing the current status of NPS” efforts to manage invasive animal species. Instead, these authors conclude that the invasive species threat “is of sufficient magnitude and urgency that it would be appropriate for the NPS to formally declare invasive animals as a service-wide priority.”

Where the Documents Agree – Sort of

Both the Panel’s report and Dayer et al. state that invasive animal threats are under-prioritized and under-funded. They say that addressing this challenge must begin at the highest levels within the NPS, engage all levels of management, and will require investments from the NPS leadership.  Even within individual parks, they acknowledge that staffs struggle to communicate the importance of invasive animal control efforts to their park leadership, especially given competition with other concerns that appear to be more urgent. And they admit that parks also lack staff capacity in both numbers and expertise.

Also, both the Panel’s report and Dayer et al. urge the NPS to acknowledge formally that invasive animals represent a crisis on par with each of the three major crises that drove Service-wide change in the past: over-abundance of ungulates due to predator control; Yellowstone fire crisis (which led to new wildfire awareness in the country); and recognition of the importance of climate change.

The Panel suggested ways to update NPS’ culture and capacity: providing incentives for staff to (1) address long-term threats (not just “urgent” ones) and (2) put time and effort into coordinating with potential partners, including other park units, agencies at all levels of government, non-governmental organizations, private landowners, and economic entities. Dayer et al. mention these barriers but does not directly mention changing incentives as one way to overcome them.

Both the Panel’s report and Dayer et al. suggest integrating invasive animal threats and management into long-range planning goals for natural and cultural landscapes and day-to-day operations of parks and relevant technical programs (e.g., Biological Resources Division, Water Resources Division, and Inventory and Monitoring Division).

What is Missing from the Journal Publication

The Panel’s final report noted the need for increased funding. It said that such funding would need to be both consistent and sufficiently flexible to allow parks to respond to time-sensitive management issues. It proposes several approaches. These include incorporating some invasive species control programs (e.g., for weeds and wood borers) into infrastructure maintenance budgets; adopting invasive species as fundraising challenges for non-governmental partners (e.g., “Friends of Park” and the National Park Foundation); and adopting invasive species as a priority threat. Dayer et al. do not discuss funding issues.

The final internal report envisioned the NPS becoming a leader on the invasive species issue by 1) testing emerging best management practices, and 2) educating visitors on the serious threat that invasive species pose to parks’ biodiversity. As part of this process, the authors suggest that the NPS also take the lead in countering invasive species denialism.  Dayer et al. do not mention the issue of invasive species deniers.

Common Ground: Status of Invasive Animals in the Parks

The Panel’s report and Dayer et al. describe the current situation similarly:

  • More than half of the National parks that responded to the internal survey (245 of the 326 parks) reported problems associated with one or more invasive animal species.
  • The total number of species recorded was 331. This is considered to be an underestimate since  staffs often lack the ability to thoroughly survey their parks – especially for invertebrates.
  • Invasive species threats to Parks’ resources have been recognized for nearly 100 years. The original report notes that 155 parks reported the presence of one or more exotic vertebrate species in 1977. At that time, exotic animals were the fourth most commonly reported source of threats. In 1991, parks identified 200 unfunded projects to address exotic species, costing almost $30 million.
  • Only a small percentage of non-native animal invasions are under active management. Dayer et al. stated that 23% have management plans at the park unit level, and only 11% are reported as being ‘‘under control”.
  • Individual parks have effective programs targetting specific bioinvaders (examples are described in Redford et al;  a brief summary of these efforts is provided in my previous blog.    

Common Ground on Some Solutions

The report and Dayer et al. promote the same steps to improve invasive animal management across the Service. Both note that the NPS is adopting formal decision support tactics to update and strengthen natural resource management across the board. More specific steps include

  • establishing a coordination mechanism that enables ongoing and timely information sharing.
  • mainstreaming invasive species issue across the NPS branches or creating a cross-cutting IAS initiative among the Biological Resources Division, Water Resources Division, Inventory and Monitoring Division, Climate Change Response Program, and the regional offices.

While both documents call on the NPS to develop and test emerging technologies, the Panel’s final  report is more detailed, providing, in Table 5, a list of several areas of special interest, including remotely triggered traps, species-specific toxicants, toxicant delivery systems, drones, environmental DNA, and sterile-male releases. Dayer et al. mention eDNA and metabarcoding for ED/RR, biocontrol, and gene drives to control invasive pathogens. (Neither document discusses possible concerns regarding use of CRISPR and other gene-altering technologies, other than to say there would be public concerns that would need to be addressed.)

Both documents note the necessity of working with resource managers beyond park boundaries to detect and manage species before they arrive in parks. They note that developing and operationalizing such partnerships requires time and resources. Furthermore, invasive species prevention, eradication, and containment programs can be effective only with public support. They suggest strengthening NPS’ highly regarded public outreach and interpretation program to build such support, including through the use of citizen scientists.

The Panel’s final report said that the NPS should recognize that the condition of the ecosystem is the objective of efforts.  Its authors recognized that achieving this goal might require reconsidering how ecosystem management is organized within NPS so interacting stressors (e.g.,  fire) and management levers (e.g., pest eradication/suppression, prescribed fire) would be addressed. For this, the NPS would need to create a focused capacity to address the pressing issue of invasive animals in such a way that fosters integrated resource management within parks, focusing on fundamental values of ecosystem states, and not eradication targets. Dayer et al. called for the same changes without specifically labelling “condition of the ecosystem” as the goal.

Publication of Dayer et al. prompted me to find out what progress the NPS has made in responding to the “key findings” in the Panel’s final report (neither publication calls them “recommendations”). 

The National Park Service has acted on the recommendation to appoint an “invasive animal coordinator” within the Biological Resources Division. That person is Jennifer Sieracki. However, I wonder whether a person located in BRD is of sufficient stature to influence agency policy across all divisions. It is not clear whether there is active coordination with the national-level invasive plant coordinator.

Dr. Sieriaki responded to my query by noting the following new efforts 1) to improve outreach to partners and the public, and 2) to expand formal and informal partnerships with local, state, federal and tribal entities and local communities near parks.

  • NPS should soon finalize two formal partnerships with other agencies and organizations for outreach and management of invasive animal species.
  • NPS is working with researchers at the US Geological Survey to expand an existing modeling tool for identifying potential suitable habitat for invasive plant species to include invasive insects. This will help staff focus on the most likely locations for introductions and thus assist with early detection and control.
  • NPS has created a Community of Practice so NPS employees can seek each other’s advice on addressing invasive animal issues. A workshop of regional invasive species coordinators is planned for the coming months to guide direction of the service-wide program and identify other top priorities. (Seriacki pers. comm.)

I also wonder whether the NPS can achieve the top-level coordination and outreach to the public called for by both reports while complying with the terms of Public Law 116-9 – the John N. Dingle Jr. Conservation, Management, and Recreation Act, which was enacted a year ago. Title VII, Section 10(i)  of this law limits spending to carry out invasive species program management and oversight to 10% of appropriated funds. Less than 15% may be spent on investigations (research), development activities, and outreach and public awareness efforts (Section 10(h)). The law does allow spending for investigations regarding methods for early detection and rapid response, prevention, control, or management; as well as inspections and interception or confiscation of invasive species to prevent in-park introductions.

For more information, see my previous criticism of NPS failure to address invasive species issues 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.

See also my earlier discussion of the new legislation here.

SOURCES

Dayer, A.A., K.H. Redford, K.J. Campbell, C.R. Dickman, R.S. Epanchin-Niell, E.D. Grosholz, D.E. Hallac, E.F. Leslie, L.A. Richardson, M.W. Schwartz. 2019. The unaddressed threat of invasive animals in U.S. National Parks.  Biol Invasions

https://doi.org/10.1007/s10530-019-02128-0

Redford, K.H., K. Campbell, A. Dayer, C. Dickman, R. Epanchin-Niell, T. Grosholz, D. Hallac, L. Richardson, M. Schwartz. 2017. Invasive animals in U. S. National Parks: By a science panel. Natural Resource Report NPS/NRSS/BRD/NRR—2017/1564. NPS, Fort Collins, Colorado. Commissioned by the NPS Chief of Biological Resources Division. https://irma.nps.gov/DataStore/DownloadFile/594922

Jennifer Sieracki, Invasive Animal Coordinator, Biological Resources Division, National Park Service

New Study: Non-Native Pests Threaten 2/5ths of 48 States’ Forest Biomass

redbay in Georgia killed by laurel wilt
photo by Scott Cameron

In August I posted a blog summarizing information on pest introductions and impacts gleaned over my nearly 30 years of engagement. Already, I need to post an update, with an alarming estimate of introduced pests’ impacts across the continent.

Fei et al. 2019 (see the full citation is at the end of this blog) estimate that the 15 most damaging introduced species threaten 41.1% of the total live forest biomass in the 48 conterminous states.

In fact, this might be an underestimate of the pests’ impacts on biomass loss. Fei et al. (2019) note several limitations in their data that might result in such an underestimate. These include:

1) Mortality rates – and impacts – may increase over several decades following the initial invasion.

2) For pests already established throughout nearly all their potential ranges, pest-induced biomass loss could be substantially underestimated because most of their hosts died long ago, before the FIA data began to be collected. Consequently, the actual loss of these tree species from the forest is much greater than has been measured by the study’s methods.

3) Mortality rates vary among species and regions, which might introduce errors. They cite European gypsy moth, in which relatively small areas of heightened mortality due to repeated defoliations are swamped by lower mortality rates across the chosen measurement area. 

4) They considered only tree mortality, not crown or root dieback or reductions in tree growth.

5) They did not estimate carbon release to the forest floor as a result of defoliation.

6) Pest-related mortality rates may be underestimated due to salvage – although the authors did not observe evidence of substantial salvage efforts for most of these pests.

7) The data did not include losses from urban tree mortality.

Fei et al. estimate that more than 450 pests are established in the 48 conterminous states. This study excluded pests attacking palms; trees on U.S. Pacific and Caribbean islands; and pests native to portions of North America that are causing severe damage in naïve hosts – e.g., goldspotted oak borer. I did include the latter groups in my slightly larger estimate laid out in my August blog.

Fei et al. base their analysis on 83 of the introduced pest species considered to cause substantial effects on tree health and productivity and sometimes extensive tree mortality. (In my August blog, I described findings by another study by Guo et al (2019) that counted 91 species in that category.)

Fei et al. build on studies by a group of USDA Forest Service (USFS) scientists that I described in an earlier blog.

This team found that, nation-wide, non-native forest pests are causing an approximate 5% increase in total annual mortality by tree volume. They based their studies on analysis of 92,978 long-term plots maintained by the USDA Forest Inventory and Analysis program.

As noted above, the article cannot capture the full range of mortality in species affected by pests introduced decades ago. Chestnut blight, white pine blister rust, Port-Orford-Cedar root disease, beech bark disease, butternut canker, dogwood anthracnose, and European gypsy moths had all killed millions of trees before the USFS forest inventory plots were established. Fei et al. do form a solid basis for measuring some of the current impacts and projecting future ones.

The focus of the new article is on the amount of carbon being transferred from live biomass to dead organic matter as a result of the increased mortality caused by the 15 species with the highest impacts. This is arguably a more quantifiable measure of pests’ impacts than others’ approaches.  Here, I focus more narrowly on the documentation of exacerbated mortality as measured by the loss of biomass. Added together, these 15 species have caused an additional (i.e., above background levels) tree mortality rate of 5.53 TgC per year [defined as terragrams of carbon]. This estimate of annual conversion of live biomass to dead wood is similar in magnitude to that attributed to fire (5.4 to 14.2 TgC per year) (Fei et al. 2019). Yet the fire threat gets much more attention – for both prevention and management.

It is important to remember that conversion of living biomass to dead wood does not result in an immediate release of carbon to the atmosphere. Atmospheric releases take place through decomposition which is both gradual and takes place at varying rates. Some of the carbon will remain in the soil. And, over time, some of the carbon storage capacity will be restored by compensatory growth in unaffected trees and the recruitment of new regeneration – although this faster growth is delayed by as much as two or more decades after pest invasions begin (Fei et al. 2019).

American elm being killed by “Dutch” elm disease
photo by Cheryl Kaiser, University of Kentucky; bugwood.org

The 15 species of introduced pests used in this analysis are laurel wilt disease, chestnut blight, butternut canker, dogwood anthracnose, emerald ash borer (EAB), Dutch elm disease, red pine scale, beech bark disease, hemlock woolly adelgid, balsam woolly adelgid, European gypsy moth, white pine blister rust, green spruce aphid, sudden oak death, and Port-Orford cedar root disease. Of these, the highest elevation in biomass loss – as measured by FIA plot data – was caused by EAB, Dutch elm disease, beech bark disease, and hemlock woolly adelgid. We know that elms and beech, at least, began dying decades before the FIA data began to be collected. So the reported mortality rates are an underestimate. This is especially true because beech mortality is highest in the first decade after invasion by beech bark disease.

Annual levels of biomass loss are virtually certain to increase. First, pests will spread to new host ranges and infestations in already-invaded ranges will intensify. As a result, substantial amounts of the hosts’ biomass are at risk of exacerbated mortality. As I noted at the top of the blog, the total amount of host biomass at risk from these 15 species is estimated to be 5,197 TgC – or 41.1% of the total live forest biomass in the 48 conterminous states. Further exacerbating future losses is the likelihood that additional pests will be introduced. I would add that pests not included in this analysis – e.g., polyphagous and Kuroshio shot hole borers and possibly the spotted lanternfly – are also likely to contribute to losses of live forest biomass.

Fei et al. (2019) did not attempt to determine the economic value of this biomass loss or to address other types of losses to ecosystem services.

Remember that a separate set of studies reported by Potter et al. (2019) (the CAPTURE project) also relied on data from the FIA plots to evaluate the impact of introduced pests. These studies focused on identifying the host species at greatest risk rather than highest-impact pests or biomass loss. I find it reassuring that the Fei and Potter studies – using different approaches – resulted in very similar species rankings. See my discussion of the Potter studies here.

Together, the teams led by Potter and Fei set clear priorities for addressing the threats from non-native pests. What we need now is action! See my recommendations in my recent “solutions” blog.

U.S. Capitol – inform your representatives that you want action to protect trees!

SOURCES

Fei, S., R.S. Morin, C.M. Oswalt, and A.M. 2019. Biomass losses resulting from insect and disease invasions in United States forests

Potter, K.M., M.E. Escanferla, R.M. Jetton, and G. Man. 2019a. Important Insect and Disease Threats to United States Tree Species and Geographic Patterns of Their Potential Impacts. Forests. 2019 10 304.

Potter, K.M., M.E. Escanferla, R.M. Jetton, G. Man, and B.S. Crane. 2019b. Prioritizing the conservation needs of United States tree species: Evaluating vulnerability to forest insect and disease threats. Global Ecology and Conservation. (2019)

Congressional Funding for Key USDA Programs (Assuming it Ever Passes)

Fiscal Year 2020 began on 1 October. Congress has not yet passed funding bills (appropriations) for the full year. Agencies are operating now on a short-term continuing resolution which expires on November 21st. Meanwhile, representatives of the House and Senate will meet to reconcile the differences between the two bodies’ appropriations bills in hope that a year-long bill can be finalized by that time.

(Disagreement between President Trump and the Congress about funding for the border wall might prevent adoption of full-year appropriations bills and lead to another government shutdown.)

I report here the differences between House and Senate bills funding the USDA APHIS and Forest Service programs that are vital to addressing non-native forest pests.

APHIS

Over the years, I have complained that inadequate funding is a major cause of shortfalls in APHIS’ efforts to detect new invasions by tree-killing pests and to respond to those invasions in effective ways.

While funding levels are still too low, at least Congress is holding funding steady for APHIS for Fiscal Year 2020 (which began three weeks ago, on October 1st). Both House and Senate bills maintain funding for two crucial programs at the FY19 levels:

  • “tree and wood pests” program – $60 million (this matches the FY19 level; it is $4 million above the funding provided in previous years); and
  • “Pest Detection” – $27.4 million.

The House provided slightly higher funding than the Senate for two other programs:

  • “specialty crops” (including sudden oak death) – $186.5 million in the House bill, $186 million in the Senate bill; and
  • “methods development” – $21.686 million in the House bill, $20.686 million in the Senate bill.

In the report accompanying its bill, the House called for two additional funding options to address emergencies. First, it set up a contingency fund of $470,000 to control outbreaks of insects, plant diseases, animal diseases and pest animals and birds to meet emergency conditions. Second, the report repeated language from past reports that authorizes the Secretary to take “such sums as may be deemed necessary” from other USDA programs in order to counter pest emergencies threatening any segment of U.S. agricultural production.

The Senate report addressed several high-profile tree pests. It called for complete eradication of the Asian longhorned beetle; mandated that APHIS report on its efforts to eradicate ALB and spotted lanternfly and to minimize spread of the polyphagous and Kuroshio shot hole borers; and to assist states that have recently detected the emerald ash borer. (This language is helpful, but it falls short of what I previously advocated – that APHIS continue efforts to prevent EAB spread, especially through movement of firewood.)  The Senate report also urged APHIS to maintain FY19 level funding addressing the sudden oak death pathogen, in particular to improve understanding of the two strains of the pathogen present in Oregon’s forests link to blog to inform control and management techniques in wildlands. (Actually, management in wildlands falls largely to the Forest Service, with scientific input from both Agriculture Research Service and – to some extent – the NORS-DUC research nursery managed by APHIS.)

For a lengthier justification of my funding requests, see my earlier blog  on APHIS funding

Funding for Resistance Breeding through NIFA

As I pointed out in my blog in May, the 2018 Farm Bill included an amendment (Section 8708) that establishes a new priority for a grant program managed by the National Institute of Food and Agriculture. The amendment would support restoration to the forest of native tree species that have suffered severe levels of mortality caused by non-native insects, plant pathogens, or other pests. The amendment affects the Competitive Forestry, Natural Resources, and Environmental Grants Program under Section 1232(c)(2) of the Food, Agriculture, Conservation, and Trade Act of 1990 (16 U.S.C. 582A-8, as amended. However, this program  has not been funded for more than a decade. In my blog, I asked you to support a $10 million appropriation to NIFA to fund a competitive grant program for such forests restoration.

Neither the House nor the Senate provided funding for this program.

USFS

The House bill provides $277,155,000 for USFS Research and Development – nearly $20 million more than the Senate bill ($257,640,000). The House report links this increase to the recognition of the increasing risk to urban, rural, and wildland forests from insect and disease outbreaks and invasive plant infestations.  The report calls on the Forest Service to develop a research program that addresses several priorities critical to forest health, including preventing the spread of disease and invasive species.

USFS engagement on pest issues with other federal agencies and state, local government, and private land managers is carried out through the Forest Health Management program under the State and Private Forestry division. The Senate bill and report are confusing because they have separated out salaries and other expenses. As a result, I can’t compare its figures to those in previous years or to those from the House. Partly for this reason, I urge you to support the House bill, which is quite clear in appropriating $103,736,000 for Forest Health Management, which is a programmatic increase of $19 million above the FY19 level and $29,919,000 above the budget request. I am encouraged by the House’ report, which encourages the Forest Service to address high priority invasive species, pests, and diseases, including the emerald ash borer and bark beetle infestations.

For longer explanations, see my earlier blog on USFS funding.

These bills show an increasing awareness of forest pest issues in key funding committees in both the House and Senate.  Let’s reinforce this message – and spread it to the rest of Congress. Please contact your senators and representative and ask them to support these funding levels.

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.

Solutions Suggested by 30 Years’ Work

Faith Campbell receives award for activism from National Association of State Foresters; 2016

For nearly 30 years I have documented bioinvasion threats and gaps, first in three Fading Forests reports (available here), then in five years of blogging. Here I pull together that information and suggest — in most cases reiterate — steps to address these threats and gaps. I list sources of discussion of the underlying issues – other than my reports and blogs – in references at the end of this blog.

My first premise is: robust federal leadership is crucial:

  1. The Constitution gives primacy to federal agencies in managing imports and interstate trade.
  2. Only a consistent approach can protect trees (and other plants) from non-native pests.
  3. Federal agencies have more resources than state agencies individually or in any likely collective effort — despite decades of budget and staffing cuts.

My second premise is: success depends on a continuing, long-term effort founded on institutional and financial commitments commensurate with the scale of the threat. This requires stable funding; guidance by research and expert staff; and engagement by non-governmental players and stakeholders. Unfortunately, as I discuss below, funding has not been adequate or stable.

My third premise is that programs’ effectiveness needs to be measured, not just effort (see the NECIS document referenced at the end of the blog).

SPECIFICS 

Preventing new introductions continues to be the most effective action. Mitigating options decrease and damages increase once a non-native pest has entered the country – much less become established (see Lovett et al. 2016 and Roy et al. 2014). I recognize that preventing new introductions poses an extremely difficult challenge given the volume and speed of international trade and the strong economic forces supporting free trade. These challenges have been exacerbated over several decades by the political zeitgeist – the anti-regulatory ideology, the emphasis on “collaborating” with “clients” rather than imposing requirements through regulations. Although the current “America First” policy might reduce import volumes and therefore reduce the invasive species threat to some extent, the anti-regulatory stance has only strengthened.

containers at the Port of Long Beach, California

Decades of cutting key agencies’ budgets and personnel are another factor. However, the damage to America’s natural systems is so great that we must try harder to find more effective strategies (See the Fading Forest reports; my previous blogs; Lovett et al. 2016; and APHIS annual reports – e.g., the 2019 report here)

Prevention

  1. Despite adoption and implementation of new international and national regulations to stem pest introductions, introductions continue – although probably at a lower level than would otherwise be the case. Delays in adoption of regulations (documented in Fading Forests II and III and my two recent 30-years-in-review blogs have facilitated damaging introductions and spread.

Solutions 

  1. Stakeholders press USDA leadership to initiate rules intended to strengthen phytosanitary protection and expedite their completion
  2. APHIS promote and facilitate analysis of current programs and policies by non-agency experts to ensure the agency is applying most effective strategies (Lovett et al. 2016).
  • Adoption of insufficiently protective regulations (documented in FFII, FFIII, two 30-years-in-review blogs) – adopted in part because APHIS is trying to “balance” trade facilitation and phytosanitary protection – has further contributed to damaging pests’ introduction and spread.

Solutions:

  1. Boost priority of preventing pest introductions by amending the Congressional finding in the Plant Protection Act [7 USC 7701(3)] as follows

Existing language: “[I]t is the responsibility of the Secretary [of Agriculture] to facilitate exports, imports and interstate commerce in . . . commodities that pose a risk of harboring plant pests or noxious weeds in ways that will reduce, to the extent practicable, as determined by the Secretary, the risk of dissemination of plant pests and noxious weeds .… “

Amend to read as follows: “…. in ways that will reduce prevent, to the greatest extent practicable feasible, as determined by the Secretary, …” [emphasis added]

  • Adopt several actions to strengthen phytosanitary protections at the point of origin (Lovett et al. 2016)
  • Expand pre-clearance partnerships — as authorized for plants under Q-37 regulations and ISPM-36
  • Expand sentinel tree programs
  • Promote voluntary substitution of packaging made from materials other than solid wood.
  • APHIS doesn’t use the enforcement powers that it has under Plant Protection Act (see several of my past blogs)

Solutions:

CBP inspectors search for pests in a pallet; CBP photo
  1. APHIS follow the lead of Customs and Border Protection and begin penalizing importers on the first instance of their wood packaging not being in compliance with ISPM#15 (see blog here).
  2. APHIS prohibit use of wood packaging by countries and importers of categories of imports that – over the 13 years since implementation – have developed a record of frequent violations of ISPM#15.
  3. APHIS use its authority per revised Q-37 regulations to negotiate with countries that export plants to the U.S. to establish “integrated measures” programs aimed at minimizing the risk of associated pests being transported to the U.S.
  4. APHIS use its authority per revised Q-37 to place in the “Not Authorized for Import Pending Pest Risk Assessment (NAPPRA) “limbo” category genera containing North American “woody” plants  (see Roy et al. 2014; Lovett et al. 2016).

Spread within the U.S.

  1. The United States lacks a coordinated system to prevent pest spread within the country (see Fading Forests III Chapter 5). Even our strictest methods, like APHIS’s quarantines regulating interstate movement of goods, have failed to curtail spread of significant pests. The most obvious example is the emerald ash borer.

The regulations governing movement of the sudden oak death pathogen in the nursery trade have also failed: there have been periodic outbreaks in which the pathogen has been spread to nurseries across the country. Between 2003 and 2011, a total of 464 nurseries located in 27 states tested positive for the pathogen, the majority as a result of shipments traced from infested wholesalers. In 2019, plants exposed to the pathogen were again shipped to 18 states; eight of those states have confirmed that their plant retailers received infected plants (see my blog from summer here).

Another serious gap is the frequent failure of APHIS and states to adopt official programs targetting bioinvaders that will be difficult to control because of biological characteristics or cryptic natures – even when severe impacts are demonstrated. Recent examples include the laurel wilt disease complex, goldspotted oak borer, polyphagous and Kuroshio shot hole borers and associated pathogens, and even the spotted lanternfly (although the last has received significant funds from APHIS.)

redbay killed by laurel wilt disease, Georgia; photo by Scott Cameron

Solutions:

  1. APHIS apply much more stringent regulations to interstate movement, based on a heightened priority for prevention in contrast to facilitating interstate trade. E.g., prohibit nurseries on the West Coast from shipping P. ramorum hosts to states where the pathogen is not established.
  2. APHIS encourage states to adopt quarantines and regulations aimed at preventing spread of invasive pests to regions of the state that are not yet infested. For example, the sudden oak death pathogen in California and Oregon; the borers in southern California.
  3. APHIS abandon plans to deregulate emerald ash borer and step up its support for state  regulations on firewood.
  4. APHIS stop dumping pests it no longer wants to regulate onto the states through the “Federally Recognized State Manage Phytosanitary (FRSMP) program”.
  5. APHIS revise its policies so that the “special needs exemption” [7 U.S.C. 7756] actually allows states to adopt more stringent regulations to prevent introduction of APHIS-designated quarantine pests (see Fading Forests III Chapter 3).

To help fill the gaps, the states are trying to coordinate their regulations in some important areas. The most advanced example is the voluntary Systems Approach to Nursery Certification, or SANC program. APHIS has supported this initiative, including by funding from the Plant Pest and Disease Management and Disaster Program (see below). However, it is a slow process; USDA funds first became available in 2010. The states are trying to coordinate on firewood, but we don’t yet know what the process will be.

  • Funding shortfalls (See the three Fading Forests reports, my blogs about appropriations)
  • Increase APHIS’ access to emergency funds from the Commodity Credit Corporation by  amending the Plant Protection Act [7 U.S.C. 7772 (a)] to include this new definition of “emergency”:

the term “emergency” means any outbreak of a plant pest or noxious weed which directly or indirectly threatens any segment of the agricultural production of the United States and for which the then available appropriated funds are determined by the Secretary to be insufficient to timely achieve the arrest, control, eradication, or prevention of the spread of such plant pest or noxious weed.

  • Although APHIS has the most robust prevention program of any federal agency, its funding is still inadequate. Stakeholders should lobby the Congress in support of higher annual appropriations.

The Plant Pest and Disease Management and Disaster Program (now under Section 7721 of the Plant Protection Act) has provided at least $77 million for tree-pest programs (excluding NORS-DUC & sentinel plant programs and other programs) since FY 2008. Much useful work has been carried out with these funds. However, these short-term grants cannot substitute for stable, long-term funding. I reiterate my call for stakeholders to lobby the Congress to provide larger appropriations to the APHIS Plant Protection program and Forest Service Forest Health Protection and Research programs.

Long-term Responses to Bioinvasive Challenge

More stakeholders are advocating raising the priority of – and providing adequate resources to – such long-term solutions as biocontrol and breeding trees resistant to pests and restoring them to our forests. Advocates include the state forestry agencies of the Northeast and Midwest, some non-governmental organizations, some academics, and individual USFS scientists. One effort resulted in inclusion of language in the 2018 Farm Bill (see blog here) – although this approach has apparently run into a dead end. The new emphasis on breeding has so far not been supported by agency or Congressional leaderships.

test planting of an American chestnut bred to be resistant to chestnut blight

Solutions:

  1. USFS convene workshop of the federal, state, National Academy, academic, and NGO groups promoting resistance breeding in order to develop consensus on priorities  and general structure of program.

Explicitly include evaluation of the CAPTURE Project’s (see blog here) efforts to set priorities to guide funding allocations and policies; and proposals for providing needed supportive infrastructure – facilities, trained staff in various disciplines. (See my blogs here.)

Report results of meeting to USDA leadership, Congress, and stakeholders

Then ensure implementation of the accepted approach by both Research and Development and Forest Health Protection programs. Include provisions to provide sustainable funding.

These proposed actions still do not address ways to correct the provisions of the international phytosanitary agreements (World Trade Organization and International Plant Protection Convention) that complicate – or preclude – efforts to prevent introduction of pests currently unknown to science. This  issue is discussed in Fading Forests II. A current example is beech leaf disease (described here).

Continuing inadequate engagement by stakeholders

Most constituencies that Americans expect to protect our forests don’t press decision-makers to fix the problems I have identified above: inadequate resources, weak and tardy phytosanitary measures. Some of these stakeholders are other federal agencies, or state agencies – or their staffs. They face restrictions on how “political” they can be. But where are the professional and scientific associations, representatives of the wood products industry, forest landowners, environmental NGOs and their funders, urban tree advocates Efforts by me, USDA, and others to better engage these groups have had disappointing results.

As I have documented, groups of USFS scientists have made several attempts to document the extent of invasive species threats and impacts and to set priorities. So far, they have not gained much traction. Another USFS attempt, Poland et al. in press, will appear at the end of the year. Will this be more successful?

I detect growing attention to educating citizen scientists for early detection; but if there is an inadequate – or no – official response to their efforts won’t people become discouraged?

SOURCES

Lovett, G.M., M. Weiss, A.M. Liebhold, T.P. Holmes,  B. Leung, K.F. Lambert, D.A. Orwig, F.T. Campbell, J. Rosenthal, D.G. McCullough, R. Wildova, M.P. Ayres, C.D. Canham, D.R. Foster, SL. Ladeau, and T. Weldy. 2016. NIS forest insects and pathogens in the US: Impacts and policy options. Ecological Applications, 26(5), 2016, pp. 1437–1455

National Environmental Coalition on Invasive Species “Tackling the Challenge.”

Poland, T.M., Patel-Weynand, T., Finch, D., Miniat, C. F., and Lopez, V. (Eds) (2019), Invasive Species in Forests and Grasslands of the United States: A Comprehensive Science Synthesis for the United States Forest Sector.  Springer Verlag. (in press).

Roy, B.A., H.M Alexander, J. Davidson, F.T Campbell, J.J Burdon, R. Sniezko, and C. Brasier. 2014. Increasing forest loss worldwide from P&Ps requires new trade regulations. Front Ecol Environ 2014; 12(8): 457–465

30 years of Analyzing Forest Pest Issues

dead whitebark pine in Crater Lake National Park
photo by F.T. Campbell

I began studying and writing about the threat to North America’s forests from non-native insects and pathogens in the early 1990s – nearly 30 years ago. I reported my analyses of the evolving threat in the three “Fading Forests” reports – coauthored by Scott Schlarbaum – in 1994, 2003, and 2014. These reports are available here.

So what has changed over those 30 years? What remains the same? Why have both the changes and the stasis occurred? What can we do to fix the gaps, close unaddressed pathways, strengthen flabby policies? I will address these issues in this and following blogs.

experimental American chestnut planted in Fairfax County, VA
photo by F.T. Campbell

What has changed since the early 1990s:

  • Adoption and implementation of significant new international and national regulations and programs aimed at preventing introductions of non-native invasive species.
  • Despite the welter of new regulations, an alarming increase in numbers of highly damaging forest pests established in the country.  (By my count, about 50 new species have established on the continent, six on Pacific islands; see details below.)
  • Alarming spread of established pests to new geographic regions and new hosts (e.g., emerald ash borer in 35 states and 5 provinces; laurel wilt disease across the range of redbay and swamp bay; rapid ‘ōhi‘a death on three of the main Hawaiian islands).
  • Introductions via unexpected pathways and vectors far removed from phytosanitary agencies’ usual targets, e.g., ship superstructures, imported steel and stone …

What has remained the same since the early 1990s:

  • Inadequate resources provided to response and recovery efforts.
  • Available funding focused on only a few of the more than 90 species causing damage.
  • Adoption of insufficiently protective regulations that have failed to prevent introduction and spread of tree-killing pests.
  • Lengthy delays in implementing programs that tighten controls – another factor in continuing introductions and spread.
  • Continued importance of expected pathways – nursery stock and raw wood, especially crates, pallets, and other forms of wood packaging.
  • Federal and state agencies still choose not to take action on pests e.g., goldspotted oak borer, polyphagous and Kuroshio shothole borers, beech leaf disease.
  • Inadequate coordination despite several efforts to set priorities.
  • Spurts of attention by media and political decision-makers, contrasted by lengthy periods of inattention.
  • Failure of most stakeholders to support efforts to prevent and respond to introductions of tree-killing pests. 

Details: The Situations Then and Now

(Many of the individual species mentioned here are described more fully here.  Full citations of sources are at the end of blog.)

American elm on the National Mall, Washington, D.C.

photo by USDA Agricultural Research Service

In 1993:

  • The number of non-native forest pest species established in the U.S. was estimated at between 300 (Millers et al. 1993) and 380 (Mattson et al., 1994; Liebhold et al., 1995) .
  • The area suffering the greatest numbers and impacts was the Northeast.
  • Several highly damaging pests that had been established for decades, including chestnut blight, white pine blister rust, Port-Orford-cedar root disease, Dutch elm disease, hemlock woolly adelgid, butternut canker, and dogwood anthracnose were receiving some attention but continued to spread.
  • USDA Forest Service funding for management of exotic pest infestations was crisis-oriented, with “… priorities … set under political pressures for immediate answers, with too much regard for short-term problems and too little consideration for broader management objectives.” (NAS 1975)
  • Since few high-profile pests had been introduced in recent years, APHIS was not actively engaged. In FY92, APHIS spent $20 million on efforts to eradicate the Asian gypsy moth. The narrow focus is illustrated by the fact that in FY93, more than two-thirds of all USDA tree pest control funds were devoted to efforts to suppress or eradicate the European gypsy moth (See FFI).
  • Concern about possible new introductions had grown; it focused on proposals to import unprocessed wood from Siberia, New Zealand, and Chile. The USDA Forest Service, academic scientists, and therefore APHIS emphasized the risks of known Asian pests, e.g., Asian gypsy moth, to western coniferous forests (See FFI). While individual scientists had expressed concern about wood packaging material, there was little public discussion of this threat.
  • We would learn later that several of the most damaging pests were already present in the country but not yet recognized – Asian longhorned beetle, sudden oak death pathogen, probably emerald ash borer.

beech leaf disease

photo by John Pogacnik

In 2019:

  • Numbers of non-native insects and pathogens attacking trees in North America approach 500 species.  (In Fading Forests III, I calculated that by the first decade of the 21st Century, the number had risen to at least 475. Several more have been detected since 2014. More than 181 exotic insects that feed on woody plants had established in Canada. (Source: USDA APHIS. 2000. Wood packaging risk assessment.)
  • Of these, 91 are considered “serious” threats (Guo et al. 2019). This estimate excludes pests native to portions of North America that are causing severe damage in naïve hosts – e.g., goldspotted oak borer; pests of palms; and pests attacking trees on U.S. Pacific and Caribbean islands.
  • Introductions had continued.
    • Between 1980 and 2016, at least 30 non-native species of wood- or bark-boring insects (Scolytinae / Scolytidae) were newly detected in the U.S. (Haack and Rabaglia 2013; Rabaglia et al.  2019). A few of these are highly damaging, e.g. redbay ambrosia beetle, polyphagous and Kuroshio shothole borers.
    • In addition to these 30 new pests, other highly damaging tree-killing pests probably introduced since the 1980s include (on the continent):
      • Eight Cerambycids such as Asian longhorned beetle (Wu et al. 2017)
      • 7 Agrilus, including emerald ash borer and soapberry borer; plus goldspotted oak borer transported from Arizona to California (Digirolomo et al. 2019; R. Haack, pers. comm.)
      • Sirex woodwasp
      • Pests of palm trees, e.g., red palm mite, red palm weevil, South American palm weevil
      • Spotted lanternfly
      • Beech leaf disease
    • Also not included in the above estimate and lists are tree-killing pests on America’s Pacific Islands :
      • ‘ōhi‘a rust
      • Cycad scale
      • Cycad blue betterfly
      • Erythrina gall wasp
      • two Ceratocystis pathogens that cause rapid ‘ōhi‘a death
      • Coconut rhinoceros beetle
    • Authorities also carried out approximately 25 eradication programs targetting introductions of the Asian gypsy moth (USDA Pest Alert Asian Gypsy Moth plus additional outbreaks since 2014).
  • Impacts of exacerbated tree mortality rates linked to these introduced pests are seen across wide swaths of the country, and affect widespread species, genera, and families. 
dead redbay in Claxton, Georgia
photo by Scott Cameron

I will discuss the risk of continuing new introductions in a separate blog.

Trying to Develop the Big Picture and Set Priorities

In recent years, USDA Forest Service scientists have made several attempts to provide nation-wide assessments of the impact of these pests and criteria for establishing priorities.

The National Insect and Disease Forest Risk Assessment predicted the loss of basal area to various pests over the 15-year time period 2012 – 2027. The assessment predicted the following losses for specific species: 90% for redbay; 60% for whitebark pine; more than 40% for limber pine; 24% for tanoak; 11% for coast live oak; 6% for eastern and Carolina hemlock; 27% for eight species of ash; 20% for American elm; 19% for red oak; 18% for American beech (Krist et al. 2014).

A separate group of scientists found that, nation-wide, non-native forest pests are causing an approximate 5% increase in total mortality by tree volume (Randy Morin at NEFPC). For details on Dr. Morin’s findings, see my blog here.

A third approach to developing a nation-wide picture, Project CAPTURE, (and my blog here) utilized FIA data to develop priorities for conservation action. Fifteen species were placed in the highest priority category, including Florida torreya (Torreya taxifolia), American chestnut and Allegheny and Ozark chinquapins, redbay, five species of ash, two species of hemlock, Port-Orford cedar, tanoak, and butternut (Potter et al. 2019(b).

According to Project CAPTURE, the non-native pests affecting the largest number of hosts are the European gypsy moth, which attacks 65 hosts; and oak wilt (Bretziella fagacearum), which infects 61 hosts. The Asian longhorned beetle attacks 43 hosts (Potter et al. 2019(b).

I note that several other non-native pests also have high numbers of host species. In the Project CAPTURE study, these pests are ranked lower because the project limited its evaluation to the five agents with the greatest effect on any particular host. Thus, of the 18 native tree species that host one or both of the invasive shothole borers and associated Fusarium disease complex (PSHB website), the project included only six. Of the 22 tree species listed by APHIS as hosts of Phytophtora ramorum, the project included 12 (K. Potter, pers. comm. April 17, 2019).

SOD-killed tanoak on the Big Sur peninsula, California
photo by Matteo Garbelotto, University of California Berkeley

More extensive discussions of non-native pests’ impacts are provided in Lovett et al. 2006, Lovett et al. 2016, and Potter et al. 2019. A book-length discussion of invasive species impacts – ranging from feral hogs to invasive plants, is expected in December; look for Poland et al. (in press).

SOURCES

Aukema, J.E., D.G. McCullough, B. Von Holle, A.M. Liebhold, K. Britton, & S.J. Frankel. 2010. Historical Accumulation of Nonindigenous Forest Pests in the Continental United States. Bioscience. December 2010 / Vol. 60 No. 11

Digirolomo, M.F., E. Jendek, V.V. Grebennikov, O. Nakladal. 2019. First North American record of an unnamed West Palaearctic Agrilus (Coleoptera: Buprestidae) infesting European beech (Fagus sylvatica) in New York City, USA. European Journal of Entomology. Eur. J. Entomol. 116: 244-252, 2019

Guo, Q., S. Fei, K.M. Potter, A.M. Liebhold, and J. Wenf. 2019. Tree diversity regulates forest pest invasion. Proceedings of the National Academy of Sciences of the United States of America. www.pnas.org/cgi/doi/10.1073/pnas.1821039116

Haack, R.A. and R.J. Rabaglia. 2013. Exotic Bark and Ambrosia Beetles in the USA: Potential and Current Invaders. CAB International 2013. Potential Invasive Pests of Agricultural Crops (ed. J. Peña) 

Krist, F.J. Jr., J.R. Ellenwood, M.E. Woods, A. J. McMahan, J.P. Cowardin, D.E. Ryerson, F.J. Sapio, M.O. Zweifler, S.A. Romero 2014. National Insect and Disease Forest Risk Assessment. United States Department of Agriculture Forest Service Forest Health Technology Enterprise Team FHTET-14-01

Leung, B., M.R. Springborn, J.A. Turner, E.G. Brockerhoff. 2014. Pathway-level risk analysis: the net present value of an invasive species policy in the US. The Ecological Society of America. Frontiers of Ecology.org

Liebhold, A. M., W. L. MacDonald, D. Bergdahl, and V. C. Mastro.  1995.  Invasion by exotic forest pests:  a threat to forest ecosystems.  Forest Sci., Monograph 30. 49 pp.

Lovett, G.M., C.D. Canham, M.A. Arthur, K.C. Weathers, and R.D. Fitzhugh. Forest Ecosystem Responses to Exotic Pests and Pathogens in Eastern North America. BioScience Vol. 56 No. 5 (May 2006)

Lovett, G.M., M. Weiss, A.M. Liebhold, T.P. Holmes,  B. Leung, K.F. Lambert, D.A. Orwig, F.T. Campbell, J. Rosenthal, D.G. McCullough, R. Wildova, M.P. Ayres, C.D. Canham, D.R. Foster, SL. Ladeau, and T. Weldy. 2016. NIS forest insects and pathogens in the US: Impacts and policy options. Ecological Applications, 26(5), 2016, pp. 1437–1455

Mattson, W. J., P. Niemela, I. Millers, and Y. Ingauazo.  1994. Immigrant phytophagous insects on woody plants in the United States and Canada: an annotated list.  USDA For. Ser. Gen. Tech. Rep. NC-169, 27 pp.

Millers, I. United States Department of Agriculture, Forest Service Entomologist, Forest Health Protection Northeastern Area State and Private Forestry. Durham, NH. Personal communication to F.T. Campbell, 1993.

Morin, R. presentation at Northeastern Forest Pest Council 81st Annual Meeting, March 12 – 14, 2019,  West Chester, Pennsylvania

National Academy of Sciences. 1975. Forest Pest Control. Washington, D.C.

Poland, T.M., Patel-Weynand, T., Finch, D., Miniat, C. F., and Lopez, V. (Eds) (2019), Invasive Species in Forests and Grasslands of the United States: A Comprehensive Science Synthesis for the United States Forest Sector.  Springer Verlag. (in press).

Polyphagous shothole borer website https://ucanr.edu/sites/pshb/overview/About_PSHB/

Potter, K.M., M.E. Escanferla, R.M. Jetton, and G. Man. 2019. Important Insect and Disease Threats to US Tree Species and Geographic Patterns of Their Potential Impacts. Forests 2019, 10, 304.

Potter, K.M., Escanferla, M.E., Jetton, R.M., Man, G., Crane, B.S. 2019. Prioritizing the conservation needs of US tree spp: Evaluating vulnerability to forest insect and disease threats, Global Ecology and Conservation (2019), doi: https://doi.org/10.1016/

Rabaglia, R.J., A.I. Cognato, E. R. Hoebeke, C.W. Johnson, J.R. LaBonte, M.E. Carter, and J.J. Vlach. 2019. Early Detection and Rapid Response. A Ten-Year Summary of the USDA Forest Service Program of Surveillance for Non-Native Bark and Ambrosia Beetles. American Entomologist Volume 65, Number 1 

USDA, Animal and Plant Health Inspection Service. 2014. Asian gypsy moth pest alert https://www.aphis.usda.gov/publications/plant_health/content/printable_version/fs_phasiangm.pdf and pers. comm.

U.S. Department of Agriculture, Animal and Plant Health Inspection Service.  2009.  Risk analysis for the movement of wood packaging material (WPM) from Canada into the US.

Wu,Y., N.F. Trepanowski, J.J. Molongoski, P.F. Reagel, S.W. Lingafelter, H. Nadel1, S.W. Myers & A.M. Ray. 2017. Identification of wood-boring beetles (Cerambycidae and Buprestidae) intercepted in trade-associated solid wood packaging material using DNA barcoding and morphology  Scientific Reports 7:40316

Promising Biocontrol to Protect Some Cacti

Photo of infested cactus at Cabo Rojo National Wildlife Refuge, Puerto Rico. Taken August 20, 2018 by Yorelyz Rodríguez-Reyes

Three and a half years ago, I blogged about the threat to columnar cacti in Puerto Rico from the Harrisia cactus mealybug. The mealybug clearly threatens the endemic cacti of the Caribbean islands, and possibly some of the hundreds of other columnar cacti growing across two million square miles of desert ecosystems that straddle the U.S.-Mexico border region.

I am pleased to report that scientists continue efforts to find biocontrol agents to reduce this insect’s damage on Caribbean islands. Much of this work is being done by the Center for Excellence in Quarantine and Invasive Species at University of Puerto Rico. The team consists of Michael West Ortiz, Yorelys Rodrígues Reyes, Ferdinand Correa and Jose Carlos Verle Rodrigues.

As of February 2019, the Center is conducting host specificity tests on a primary parasitoid of the Harrisia Cactus mealybug — Anagyrus cachamai. This wasp was found as a result of almost a decade of searching in South America and other locations. It is native to Argentina and Paraguay (Triapitsyn et al. 2018; sources listed at the end of the blog).The Center also continues surveys and studies of other primary and secondary parasitoids of the mealybug.

The work to develop a biocontrol agent for the mealybug continues despite continuing uncertainty about the true species of the mealybug. At the time of its discovery on Puerto Rico, the mealybug was believed to belong to a species used as a biocontrol agent for invasive cacti in Australia and South Africa, designated as Hypogeococcus pungens. However, H. pungens is now thought to be a species complex, and the species in Puerto Rico differs from the earlier designation (Triapitsyn et al. 2018). 

Apparently the mealybug was introduced in Puerto Rico around 2000   — probably on the ornamental common purslane (Portulaca olerácea), an annual succulent. (Note: the introduction was on a host different from the vulnerable cacti.) Within five years of the first detection in San Juan, the mealybug was sighted on cacti on the other side of the island in the Guánica State Forest and Biosphere Reserve. By 2010, the mealybug was widely distributed in most dry districts. Surveys found it in all 11 municipalities surveyed in southern Puerto Rico. At some locations, infestation levels were extremely high – e.g., 86% of stems surveyed were infested at Guánica. Infestation rates were lower in other municipalities. As of 2010, infestations were estimated to be present on about 1,400 km2 on the southern coast; the rate of new infestations suggests that the mealybug was spreading rapidly (Segarra-Carmona et al. 2010).  I have been unable to obtain more recent estimates.

The mealybug impacts seven of 14 native cactus species occurring in dry forests of the island, including three endemic and two endangered species in the subfamily Cactoideae. The two endangered species are Harrisia portoricensis and Leptocereus grantianus (USDA ARS). The tissue damage caused by the mealybug interferes with sexual reproduction and can cause direct mortality of the plant (Triapitsyn et al. 2018).  These cacti provide food or shelter for endemic bats, birds, moths and other pollinators (Segarra & Ramirez; USDA ARS). The mealybug is also now killing native cacti on the U.S. Virgin Islands (H. Diaz-Soltero pers. comm. August 2015).

 USDA Funds Conservation Efforts Despite Apparent Absence of a Constituency Calling for Such Action

Efforts to identify and test possible biocontrol agents targetting the Harrisia cactus mealybug received significant funds from the Plant Pest and Disease Management and Disaster Prevention Program. This is a competitive grant program managed by APHIS. It is permanently funded and thus not subject to the vagaries of annual appropriations. Until last year, this program operated under Section 10007 of the 2014 Farm Bill. With passage of a new Farm Bill, it is now designated as Section 7721 of the Plant Protection Act.

Since Fiscal Year 2018, APHIS has had authority to spend more than $60 million per year on this program.  In Fiscal Year 2017, , the program provided $120,000 to an unspecified federal agency, $70,000 to an academic institution in Puerto Rico (presumably the Center), $15,000 to another academic institution in California, and $3,000 divided among two APHIS facilities – for a total of $208,000. The next round of funds came in FY19, when the program provided $277,267 to an unspecified federal agency to continue work on biocontrol. In addition, the program provided $78,507 to an unspecified federal agency to “safeguard[e] genetic diversity of native and listed cacti threatened by Harrisia cactus mealybug in Puerto Rico”.

No Apparent Action on Threats to Opuntia Cacti

In my earlier blog, I also described the threat to flat-padded Opuntia (prickly pear) cacti from the cactus moth Cactoblastis cactorum. Various federal, state, and academic entities received $463,000 from the permanent fund in Fiscal Year 2016 and another $100,000 in FY2017. No cactus moth programs have received funds in more recent years.

SOURCES

Segarra-Carmona, A.E., A. Ramirez-Lluch. No date. Hypogeococcus pungens (Hemiptera: Pseudococcidae): A new threat to biodiversity in fragile dry tropical forests.

Segarra-Carmona, A.E., A. Ramírez-Lluch, I. Cabrera-Asencio and A.N. Jiménez-López. 2010.  FIRST REPORT OF A NEW INVASIVE MEALYBUG, THE HARRISIA CACTUS MEALYBUG HYPOGEOCOCCUS PUNGENS (HEMIPTERA: PSEUDOCOCCIDAE). J. Agrie. Univ. RR. 94(1-2):183-187 (2010)

Triapitsyn, Aguirre, Logarzo, Hight, Ciomperlik, Rugman-Jones, Rodriguez. 2018. Complex of primary and secondary parasitoids (Hymenoptera: Encyrtidae and Signiphoridae) of Hypogeococcus spp. mealybugs (Hemiptera: Pseudococcidae) in the New World. Florida Entomologist Volume 101, No. 3 411

USDA Agriculture Research Service, Research Project: Biological Control of the Harrisia Cactus Mealybug, Hypogeococcus pungens (Hemiptera:pseudococcidae) in Puerto Rico Project Number: 0211-22000-006-10 Project Type: Reimbursable

West Ortiz, M. pers. comm. February 2019

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.

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.