emerald ash borer; some of PPA grants are funding evaluation of biocontrol efficacy
USDA APHIS has released information about its most recent annual allocation of funds under the Plant Pest and Disease Management & Disaster Prevention Program under §7721 of the Plant Protection Act. (Also see Fading Forests II and III; links provided at the end of this blog.) These funds support both critical needs and opportunities to strengthen the nation’s infrastructure for pest detection, surveillance, identification, and threat mitigation. Since 2009, this USDA program has provided nearly $940 million to more than 5,890 projects.
For FY25 APHIS allocated $62.725 million to fund 339 projects, about 58% of the proposals submitted. About $10 million has reserved for responding to pest and plant health emergencies throughout the year.
According to APHIS’ press release, the highest amount of funds (almost $16 million) is allocated to the category “Enhanced Plant Pest/Disease Survey.” Projects on “Enhanced Mitigation Capabilities” received $13.6 million. “Targetting Domestic Inspection Efforts to Vulnerable Points” received nearly $6 million. “Improving Pest Identification and Detection Technology” was funded at $5 million. Outreach & education received $4 million. I am not sure why these do not total $63 million.
Funding for States and Specific Pests
Wood-boring insects received about $2.3 million. These included more than $869,800 to assess the efficacy of biocontrol for controlling emerald ash borer (EAB) Agrilus planipennis, $687,410 was provided for various detection projects, and $450,000 for outreach efforts related to various pests. Ohio State received $93,000 to optimize traps for the detection of non-native scolytines (bark beetles).
Biocontrol efficacy will also be assessed for hemlock woolly adelgid, invasive shot hole borers, cactus moth, and several invasive plants (including Brazilian pepper). (Contact me to obtain a copy of CISP’s comments on this biocontrol program.)
Opuntia basilaris in Anza Boreggo; one of flat-padded Opuntia vulnerable to the cactus moth; photo by F.T. Campbell
Funding for other pests exceeded $1 million for spotted lanternfly (nearly $1.4 million), Asian defoliators ($1.2 million) and box tree moth (just over $1 million).
$630,000 was provided for detection surveys and studies of the sudden oak death pathogen Phytophthora ramorum, especially how it infects nursery stock. Nursery surveys are funded in Alabama, Louisiana, North Carolina, Ohio, Oklahoma, Pennsylvania, South Carolina, Tennessee, Virginia, and West Virginia. Most of these states are in regions considered most at risk to SOD infection of wildland plants.
sudden oak mortality of tanoak trees in southern Oregon; photo by Oregon Department of Forestry
Oregon received much-deserved $41,000 to evaluate the threat of the NA2 and EU2 lineages of P. ramorum to nurseries and forests Oregon also received $104,000 to respond to the detection of Phytophthora austrocedri in nurseries in the state. The Oregon outbreak has been traced to Ohio, but I see no record of funds to assist that state in determining how it was introduced.
Asian defoliator (e.g., Lymantrid moths) surveys have been funded for several years. This year’s projects are in Alaska, Arkansas, California, Kentucky, Maryland, Massachusetts, Mississippi, Montana, Nevada, North Carolina, Oregon, Tennessee, Texas, Washington, and West Virginia. While I agree that the introduction risk is not limited to coastal states with maritime ports, I don’t what criteria were applied in choosing the non-coastal states which are funded to search for these insects
Spotted lanternfly surveys (including technological improvements) or related outreach are funded in Alabama, Connecticut, Delaware, Kentucky, New Hampshire, New Jersey, North Carolina, Oregon, Pennsylvania, and Tennessee. California’s project is focused on postharvest treatments.
The Don’t Move Firewood project continues to be funded by APHIS. Several states also direct attention specifically to the firewood pathway: Kentucky, Maine, and Michigan.
I applaud the precautionary funding of the Agriculture Research Service to generate of high-quality genomic resources for managing the causal agent of Japanese oak wilt Dryadomyces quercivorous
Florida Department of Agriculture, North Carolina State University, and West Virginia University each received more than $100,000 to improve detection and management of invasive hornets.
Tennessee State University got $100,000 to continue efforts to detect and understand Vascular Streak Dieback in redbud Cercis canadensis.
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.
For a detailed discussion of the policies and practices that have allowed these pests to enter and spread – and that do not promote effective restoration strategies – review the Fading Forests report at https://treeimprovement.tennessee.edu/
Woldstedtius flavolineatus – one of at least 13 taxa of non-native ichneumonid wasps established in restoration forests in Hawaiian Forest National wildlife rfefuge; photo by Torgrim Breiehagen for the Norwegian Biodiversity Information Centre; via Wikipedia
As we know, non-native insects and pathogens pose a significant and accelerating threat to biodiversity in forests and other ecosystems. They undermine some conservation programs and reduce ecosystem services and quality of life in urban areas. Nevertheless, damaging introductions continue.
Two recent articles have advocated accelerating biocontrol programs. These articles have reminded us of ongoing failures of international and national biosecurity programs, including that of the US. The articles also make interesting suggestions regarding ways to be more pro-active in preventing introductions.
1. “Self-introductions” of invaders’ enemies
Weber et al. (full citation at end of blog) provide many examples of unintentional “self-introductions” of natural enemies of arthropod pests and invasive plants. In fact, “self-introductions” of natural enemies of arthropod pests might exceed the number of species introduced intentionally. These introductions have been facilitated by the usual factors: the general surge in international trade; lack of surveillance for species that are not associated with live plants or animals; inability to detect or intercept microorganisms; huge invasive host populations that allow rapid establishment of their accidentally introduced natural enemies; and lack of aggressive screening for pests already established.
Among the examples illustrating failures of biosecurity programs:
Across six global regions, nearly two-thirds of parasitoid Hymenoptera species were introduced unintentionally. The proportion varies significantly by region. For example, four-fifths of these insects in New Zealand arrived accidentally.
The unintentional spread of the glassy-winged sharpshooter (Homalodisca vitripennis) and a biocontrol agent Cosmocomoidea ashmeadi has been so rapid among islands in the Pacific Ocean (including Hawai`i) they are considered ‘biomarkers’ of biosecurity failures.
Regarding the United States specifically, an estimated 67% of beneficial insects introduced to Hawai`i and 64% of parasitoid Hymenoptera introduced to the mainland U.S. were accidental “self-introductions.”
Weber et al. consider their figures to be underestimates. The situation is particularly uncertain regarding pathogens that kill arthropods. Many microbial species are not yet described.
spotted lanternfly; photo by Stephen Ausmus, USDA
In some cases, these “self-introduced” arthropods have proved beneficial. Two examples are Entomophaga maimaiga and Lymantria dispar nucleopolyhedrovirus (LdNPV), which help control the spongy moth (Lymantria dispar). In other cases the “self-introduced” creatures are pests themselves. A prominent example is the invasion by the spotted lanternfly (Lycorma delicatula). This was facilitated by the widespread presence of the highly invasive plant Ailanthus altissima. It illustrates what Weber et al. call “receptive bridgehead effects.” That is, once an invasive pest is well-established, the chance that its natural enemies will find a suitable host and also establish in the pest’s invaded range is much higher.
Weber et al. reaffirm that there are many good reasons not to allow such random invasions of diverse non-native species – including their natural enemies. Deliberately introduced biocontrol agents are chosen after determining their efficacy, host-specificity, and climatic suitability. Random introductions, on the other hand, might favor generalist species, which could threaten non-target species. Accidental introductions might also be accompanied by pathogens and hyperparasitoids that could compromise the efficacy of biocontrol agents.
In short, unintentionally introduced natural enemies might have about the same level of success in controlling the target pest’s populations as do intentionally introduced agents. However, unintentional introductions of both pests and pathogens carry additional risks of non-target impacts and contamination with their own natural enemies that would hamper the efficacy of the biocontrol agent. Weber et al. conclude that delays in releasing a deliberately chosen and evaluated biocontrol agent reduce the probability that it will successfully establish instead of an unintentionally introduced organism.
cactus moth larva on Opuntia; photo by Doug Beckers via Flickr
It is especially likely that an arthropod – whether or not a biocontrol agent – will spread within a geographic region. Weber et al. say both the U.S. and Canada have received more than a dozen species intentionally introduced into the other country. They also cite spread of the cactus moth, Cactoblastis cactorum, into Florida from several Caribbean countries. The cactus moth has spread and now threatens the center of diversity of flat-padded Opuntia cacti in the American southwest and Mexico.
Another example is California: 44% of invading terrestrial macroinvertebrates that have established in the state came from populations established elsewhere in the US and Canada (Hoddle 2023). This number exceeds the total number of invasive macroinvertebrates in the state that originated anywhere in Eurasia (Weber et al.).
True, it is very difficult to prevent natural spread. But a lot of this spread is facilitated by human activities, e.g., transporting vectors such as living plants, firewood, outdoor furniture or storage “pods.” I have complained often — here and here and here — that interstate movement of invasive plant pests is particularly poorly controlled.
Some scientists and regulators have responded to these situations by improving phytosanitary programs. California officials, in 2019, set up a program to fund projects aimed at developing integrated pest management strategies for species thought to have a high invasion potential before they arrive. I urge other states to do the same. This would probably be most effective in controlling the target species – and in relation to cost — if developed by regional consortia.
Weber et al. suggest that given continuing unintentional introductions of non-native species, phytosanitary agencies need to focus on those invasion pathways that are particularly likely to result in invasions, e.g. live plants, raw lumber (including wood packaging), and bulk commodities e.g.quarried rock.
The authors also suggest research opportunities that arise from biocontrol agents’ “self-introductions”. These include:
Comparing actual host ranges to those predicted by laboratory and other studies;
Quantifying the role of Allee effects, for example by studying the spread of the glassy-winged sharpshooter and its biocontrol agent across the Pacific region;
Usingmolecular analyses to disentangle multiple routes of entry (e.g., the “invasive bridgehead effect”) and hybridization.
2. Door-knocker species
Hoddle (2023) suggests further that early detection programs should focus on “door-knocker” species — those likely to enter and cause significant negative impacts. In an earlier article (Hoddle, Mace and Steggall 2018) argued that the benefits of a pro-active biocontrol program outweigh the costs. The authors say the information gained would cut the time needed to deploy effective biocontrol. Ultimately, this could reduce the prolonged and even irreversible ecological and economic disruption from invasive pests, associated pesticide applications, and lost ecological services.
Asian citrus psyllid (Diaphorina citri); USDA photo by Justin Wendell; Hoddle cites this species as one that a pro-active biocontrol program should have targetted
Hoddle calls funding pro-active biocontrol research programs before they’re needed as analogous to buying insurance. The owners of insurance policies hope not to need them but benefit when catastrophe strikes. Furthermore, the information gained from early research might identify natural enemy species that could “self-introduce” along with the invading host. Finally, proactive research might clarify whether the increasing number of natural enemy species that are “self-introducing” pose a threat to non-target organisms.
Recognizing the difficulty of identifying an “emerging invasive species” before its introduction, Hoddle endorses other components of prevention programs:
Collaborating with non-U.S. scientists to identify and mitigate invasion bridgeheads. Such efforts would both lessen bioinvasion threats and possibly aid in determining native ranges and facilitating location of natural enemies.
Sentinel plantings, such as those established under the International Plant Sentinel Network. These plantings can also support research on natural enemies of key pests.
Integrating online platforms, networks, professional meetings, and incursion monitoring programs into “horizon scans” for potential invasive species. He mentions specifically PestLens; online community science platforms, e.g., iNaturalist; international symposia; and official pest surveillance, e.g., U.S. Forest Service’s bark beetles survey and surveys done by the California Department of Food and Agriculture and border protection stations.
date palm mealybug (Pseudaspidoproctus hyphaeniacus); threat to native Washingtonia palms of California; one of pests tracked by PestLens
Weber et al. also support the concept of sentinel plant nurseries – especially because accidental plant and herbivore invasions often occur at the same points of entry.
Both Weber et al. and Hoddle urge authorities not to strengthen regulations governing biocontrol introductions. Weber et al. say that would be to make perfect the enemy of the good. The need is to balance solving problems with avoiding creation of new problems.
SOURCES
Hoddle, M.S., K. Mace, J. Steggall. 2018. Proactive biological control: A cost-effective management option for invasive pests. California Agriculture. Volume 72, No. 3
Weber, D.C. A.E. Hajek, K.A. Hoelmer, U. Schaffner, P.G. Mason, R. Stouthamer, E.J. Talamas, M. Buffington, M.S. Hoddle, and T. Haye. 2020. Unintentional Biological Control Chapter for USDA Agriculture Research Service. Invasive Insect Biocontrol and Behavior Laboratory. https://www.ars.usda.gov/research/publications/publication/?seqNo115=362852
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.
For a detailed discussion of the policies and practices that have allowed these pests to enter and spread – and that do not promote effective restoration strategies – review the Fading Forests report at http://treeimprovement.utk.edu/FadingForests.htm
African Tulip Tree (Spathodea campanulata) on Puerto Rico; photo by Joe Schlabotnik via Flickr
While it is widely accepted that tropical island ecosystems are especially vulnerable to invasions, there has been little attention to terrestrial bioinvaders in the Caribbean; there has been more attention to marine bioinvaders such as lionfish. I am glad that is starting to change. Here I review a new study by Potter et al. (full citation at end of this blog), supplemented by information from other recent studies, especially Poland et al.
Potter et al. used USFS Forest Inventory and Analysis (FIA) survey data to examine regeneration rates by non-native tree species introduced to the continental United States, Hawai`i, and Puerto Rico. I rejoice that they have included these tropical islands, often left out of studies. They are part of the United States and are centers of plant endemism!
Potter et al. sought to learn which individual non-indigenous tree species are regenerating sufficiently to raise concern that they will cause significant ecological and economic damage in the future. That is, those they consider highly invasive. They defined such species as those for which at least 75% of stems of that species detected by FIA surveys are in their small tree categories – saplings or seedlings. They concluded that these species are successfully reproducing after reaching the canopy so they might be more likely to alter forest ecosystem functions and services. They labelled species exhibiting 60 – 75% of stems in the “small” categories as moderately invasive.
The authors recognize that many factors might affect tree species’ regeneration success, especially at the stand level. They assert that successful reproduction reflects a suite of factors such as propagule pressure, time since invasion, and ability of a species to adapt to different environments.
As I reported in an earlier blog, link 17% of the total flora of the islands of the Caribbean archipelago – including but not limited to Puerto Rico – are not native (Potter et al.). In Puerto Rico, two-thirds of forests comprise novel tree assemblages. The FIA records the presence of 57 non-native tree species on Puerto Rico. Potter et al. identified 17 non-native tree species as highly invasive, 16 as potentially highly invasive, and two as moderately invasive. That is, 33 of 57 nonnative tree species, or 58% of those species tallied by FIA surveyors, are actual or potential high-impact bioinvaders. While on the continent only seven non-native tree species occurred on at least 2% of FIA plots across the ecoregions in which they were inventoried, on Puerto Rico 21 species occurred on at least 2% of the FIA plots (38%). They could not assess the invasiveness of the eight species that occurred only as small stems on a couple of survey plots. These species might be in the early stages of widespread invasion, or they might never be able to reproduce & spread.
The high invasion density probably reflects Puerto Rico’s small size (5,325 mi² / 1,379,000 ha); 500 years of exposure to colonial settlement and global trade; and wide-scale abandonment of agricultural land since the middle of the 20th Century
Naming the invaders
The most widespread and common of the highly invasive non-native tree species are river tamarind (Leucaena leucocephala), on 12.6% of 294 forested plots; algarroba (Prosopis pallida) on 10.9%; and African tuliptree (Spathodea campanulata)on 6.1%. Potter et al. attribute the prevalence of some species largely to land-use history, i.e., reforestation of formerly agricultural lands. In addition, some of the moderately to highly invasive species currently provide timber and non-timber forest products, including S.campanulata, L. leucocephala, Syzgium jambos (rose apple) and Mangifera indica (mango).
Potter et al. contrast the threat posed by Spathodea campanulata with that posed by Syzgium jambo. The latteris shade tolerant and can form dense, monotypic stands under closed canopies. Because it can reproduce under its own canopy, it might be able to remain indefinitely in forests unless it is managed. In contrast S. campanulata commonly colonizes abandoned pastures. Since it is shade intolerant, it might decline in the future as other species overtop it. Meanwhile, they suggest, S. campanulata might provide habitat appropriate for the colonization of native tree species.
Second-growth forest in Caribbean National Forest “El Yunque”
Poland et al. say the threat from Syzgium jambos might be reduced by the accidentally introduced rust fungus Puccinia psidii (= Austropuccinia psidii), which has been killing rose apple in Puerto Rico. In Hawai`i, the same fungus has devastated rose apple in wetter areas.
Potter et al. note that stands dominated by L. leucocephala and Prosopis pallida in the island’s dry forests are sometimes arrested by chronic disturbance – presumably fire. However, they do not report whether other species – native or introduced – tend to replace these two after disturbance. The authors also say that areas with highly eroded soils might persist in a degraded state without trees. The prospect of longlasting bare soil or trashy scrub is certainly is alarming.
Potter et al. warn that the FIA’s sampling protocol is not designed to detect species that are early in the invasion process. However, they do advise targetting eradication or control efforts on the eight species that occurred only as small stems on a couple of survey plots. While their invasiveness cannot yet be determined, these species might be more easily managed because presumably few trees have yet reached reproductive age. They single out Schinus terebinthifolius (Brazilian pepper), since it is already recognized as moderately invasive in Hawai`i. I add that this species is seriously invasive in nearby peninsular Florida and here! APHIS recently approved release of a biocontrol insect in Florida targetting Brazilian pepper. It might easily reach nearby Puerto Rico or other islands in the Caribbean. I am not aware of native plant species in the Caribbean region that might be damaged by the biocontrol agent. However, two native Hawaiian shrubs might be harmed if/when this thrips reaches the Hawaiian Islands. Contact me for specifics, or read the accompanying blog about Potter et al. findings in Hawai`i.
Poland et al. looked at the full taxonomic range of possible bioinvaders in forest and grassland ecosystems. The Caribbean islands receive very brief coverage in the chapter on the Southeast (see Regional Summary Appendices). This chapter contains a statement that I consider unfortunate: “Introduction of species has enriched the flora and fauna of Puerto Rico and the Virgin Islands.” The chapter’s authors assert that many of the naturalized species are restoring forest conditions on formerly agricultural lands. They say that these islands’ experience demonstrates that introduced and native species can cohabitate and complement one another. I ask – but in what kind of forest? These forests, are novel communities that bear little relationship to pre-colonial biodiversity of the islands. Was not this chapter the right place to note that loss? Forests are more than CO2 sinks.
I also regret that the chapter does not mention that the Continental United States can be the source of potentially invasive species (see several examples below).
Mealybug-infested cactus at Cabo Rojo National Wildlife Refuge, Puerto Rico. Photo by Yorelyz Rodríguez-Reyes
The chapter does concede that some introduced species are causing ecological damage now. See Table A8.1. Some of these troublesome introduced species are insects:
the South American Harrisia cactus mealybug (Hypogeococcus pungens) is killing columnar cacti in the islands’ dry forests. The chapter discusses impacts on several cactus species and control efforts, especially the search for biocontrol agents.
the agave snout weevil (Scyphophorus acupunctatus), native to the U.S. Southwest and Mexico , is threatening the endemic and endangered century plant (Agave eggersiana) in St. Croix & Puerto Rico.
Tabebuia thrips (Holopothrips tabebuia) is of unknown origin. It is widespread around mainland Puerto Rico. Its impacts so far are primarily esthetic, but it does apparently feed on both native and introduced tree species in the Tabebuia and Crescentia genera.
The Caribbean discussion also devotes welcome attention to belowground invaders, i.e., earthworms. At least one species has been found in relatively undisturbed cloud forests, so it is apparently widespread. Little is known about its impact; more generally, introduced earthworms can increase soil carbon dioxide (CO2) emissions as through speeded-up litter decomposition and soil respiration.
A factsheet issued by the British forestry research arm DEFRA reports that the pine tortoise scale Toumeyella parvicornis has caused the death of 95% of the native Caicos pine (Pinus caribaea var. bahamensis) forests in the Turks and Caicos Islands (a UK Overseas Territory). The scale is native to North America. It has recently been introduced to Italy as well as to Puerto Rico, and the Turks and Caicos Islands.
SOURCES
Lugo, A.E., J.E. Smith, K.M. Potter, H. Marcano Vega, C.M. Kurtz. 2022. The Contribution of Non-native Tree Species to the Structure & Composition of Forests in the Conterminous United States in Comparison with Tropical Islands in the Pacific & Caribbean. USFS International Institute of Tropical Forestry General Technical Report IITF-54.
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. Especially the Appendix on the Southeast and Caribbean. Springer Verlag. Available gratis at https://link.springer.com/book/10.1007/978-3-030-45367-1
Potter K.M., Riitters, K.H. & Guo. Q. 2022. Non-nativetree regeneration indicates regional & national risks from current invasions. Frontiers in Forests & Global Change Front. For. Glob. Change 5:966407. doi: 10.3389/ffgc.2022.966407
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.
For a detailed discussion of the policies and practices that have allowed these pests to enter and spread – and that do not promote effective restoration strategies – review the Fading Forests report at http://treeimprovement.utk.edu/FadingForests.htm
Phytophthora ramorum-infected rhododendron plant; photo by Jennifer Parke, Oregon State University
APHIS has released the list of projects funded under §7721 of the Plant Protection Act in Fiscal Year 2023. Projects funded under the Plant Pest and Disease Management and Disaster Prevention Program (PPDMDPP) are intend to strengthen the nation’s infrastructure for pest detection and surveillance, identification, threat mitigation, and safeguard the nursery production system.
APHIS has allocated $62.975 M to fund 322 projects in 48 states, Guam, & Puerto Rico. ~ $13.5 M has been reserved for responding to pest and plant health emergencies throughout the year. USDA is funding ~70% of the more than 460 PPDMDPP proposals submitted.
2 – Target Domestic Inspection Activities at Vulnerable Points $6,356,964
3 – Pest Identification and Detection Technology Enhancement $5,295,125
4 – Safeguard Nursery Production $2,079,119
5 – Outreach and Education $4,131,333
6 – Enhance Mitigation Capabilities $13,875,775
By my calculation (subject to error!), the total for projects on forest pests is ~$6.5 M – or a little over 10% of the total. The top recipient was survey and management of sudden oak death: ~$700,000 for research at NORS-DUC and NCSU plus detection efforts in nurseries of 14 states. Other well-funded efforts were surveys for bark beetles and forest pests (projects in 14 states); surveys for Asian defoliators (projects in 14 states); and outreach programs targetting the spotted lanternfly (10 states, plus surveys in California).
Three states (Iowa, Kentucky and Maryland) received funding for surveys targetting thousand cankers disease of walnut; two states (Kentucky and Maine) obtained funding for outreach about the risk associated with firewood. Funding for the Nature Conservancy’s “Don’t Move Firewood” campaign appears under the home state of its leader, Montana.
Massachusetts obtained funding for outreach re: Asian longhorned beetle. Ohio State received funding for developing a risk map for beech leaf disease.
Ten states received funding for no forest pest projects; I don’t know whether they sought funding for this purpose. These states are Arizona, Colorado, Florida, Hawai`i, Idaho, Minnesota, Nebraska, New Mexico, North Dakota, and Puerto Rico. The “National” funding category also contained no forest pest projects.
Looking at the overall funding level might give a somewhat skewed impression because several of the projects with total funding of ~ $500,000 are actually carried out by USDA agencies. These awards are listed under the state in which the USDA facility happens to be located. Nearly half this money ($213,000) goes to a project by an Agriculture Research Service unit in Delaware to study the efficacy of the biocontrol targetting emerald ash borer. Another $105,588 is allocated to detection of the SOD pathogen (Phytophthora ramorum) in irrigation water, undertaken – I think – at the ARS quarantine facility in Frederick, Maryland. A smaller project at a USFS research facility in Connecticut is studying egg diapause in the spotted lanternfly. The Delaware ARS unit is also pursuing biological control of the red-necked longhorn beetle (RNB) Aromia bungi, which attacks primarily stone fruits. Native to China and other countries in Asia, RNB has been intercepted in wood packaging by the U.S. and Europe; it has become established in Italy and Japan [Kim Alan Hoelmer, ARS, pers. comm.] The APHIS lab in Massachusetts is developing a light trap for detection of the Asian spongy mothsLymantria dispar.
I am intrigued that two states (Mississippi and Nevada) are conducting “palm commodity” surveys. Palms are important components of the environment in some states – although I am not certain these are the two most important!
As you might remember, I am also interested in some invaders other than forest pests. Washington has obtained $998,000 to support two projects integral to its efforts to find and eradicate the Asian (or Northern) Giant hornet. Oregon has obtained funding to carry out a survey for these hornets.
Cactus moth larvae feeding on prickly pear cactus; photo by Doug Beckers, via Flickr
I rejoice to see that the Florida Department of Agriculture continues efforts to deploy biocontrol agents targetting the cactus moth. The Agriculture Research Service is evaluating the establishment of biocontrol agents released to counter two highly invasive plants. Re: Brazilian peppertree, I don’t question the damage it has caused in southern Florida but I have grave concerns should the psyllid and thrips reach Hawai`i. I am most distressed to see that Hawaiian Division of Forestry and Wildlife and Department of Agriculture are actively pursuing deliberate introduction of the thrips. ARS is also searching for potential biocontrol agents targetting the invasive cogongrass (Imperata cylindrica). Penn State is working on registering a soil fungus native to North America, Verticillium nonalfalfae, as a biocontrol targetting the highly invasive tree of heaven (Ailanthus).
Phragmites invading Merkle Wildlife Sanctuary, Upper Marlboro, Maryland; photo by Alicia Pimental, (c) Chesapeake Bay Foundation
APHIS is pursuing biocontrol for “Roseau” cane scale. This situation presents a conflict of geographic regions because the plant to be controlled is Phragmites australis.Phragmitesis highly invasive in the Mid-Atlantic, Northeast, and Great Lakes states . On the Mississippi delta it is considered important in maintaining wetlands crucial to protecting the Louisiana coast from rising seas.
Finally, USDA is pursuing management tools to contain the Box Tree Moth – a threat to the most widely planted ornamental shrub.
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.
For a detailed discussion of the policies and practices that have allowed these pests to enter and spread – and that do not promote effective restoration strategies – review the Fading Forests report at http://treeimprovement.utk.edu/FadingForests.htm
APHIS is seeking stakeholder input to its new strategic plan to guide the agency’s work over the next 5 years.
The strategic plan framework is a summary of the draft plan; it provides highlights including the mission and vision statements, core values, strategic goals and objectives, and trends or signals of change we expect to influence the agency’s work in the future. APHIS is seeking input on the following questions:
Are your interests represented in the plan?
Are there opportunities for APHIS to partner with others to achieve the goals and objectives?
Are there other trends for which the agency should be preparing?
Are there additional items APHIS should consider for the plan?
range of American beech – should APHIS be doing more to protect it from 3 non-native pests?
Comments must be received by July 1, 2022, 11:59pm (EST).
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.
For a detailed discussion of the policies and practices that have allowed these pests to enter and spread – and that do not promote effective restoration strategies – review the Fading Forests report at http://treeimprovement.utk.edu/FadingForests.htm
sassafras – vulnerable to the rapidly spreading laurel wilt disease; photo by F.T. Campbell
In summer 2019 I posted several blogs summarizing my analysis of forest pest issues after 30 years’ engagement. I reported the continuing introductions of tree-killing insects and pathogens; their relentless spread and exacerbated impacts. I noted the continued low priority given these issues in agencies tasked with preventing and solving these problems. Also, Congress provides not only insufficiently protective policies but also way too little funding. I decried the impediments created by several Administrations; anti-regulatory ideology and USDA’s emphasis on “collaborating” with “clients” rather than imposing requirements.
In my blogs, I called for renewed effort to find more effective strategies – as I had earlier advocated in my “Fading Forests” reports (link provided at the end of this blog), previous blogs, and Lovett et al. 2016
Areas of Progress
Now two years have passed. I see five areas of progress – which give me some hope.
1) Important Activities Are Better Funded than I had realized
a) The US Forest Service is putting significant effort into breeding trees resistant to the relevant pests, more than I had realized. Examples include elms and several conifer species in the West – here and here.
b) USDA has provided at least $110 million since FY2009 to fund forest pest research, control, and outreach under the auspices of the Plant Pest and Disease Disaster Prevention Program (§10201 of the Farm Bill). This total does not include additional funding for the spotted lanternfly. Funded projects, inter alia: explored biocontrol agents for Asian longhorned beetle and emerald ash borer; supported research at NORS-DUC on sudden oak death; monitored and managed red palm weevil and coconut rhinoceros beetle; and detected Asian defoliators. Clearly, many of these projects have increased scientific understanding and promoted public compliance and assistance in pest detection and management.
This section of the Farm Bill also provided $3.9 million to counter cactus pests – $2.7 million over 10 years targetting the Cactoblastismoth & here and $1.2 million over four years targetting the Harissia cactus mealybug and here.
flat-padded Opuntia cactus – vulnerable to the Cactoblastis moth; National Park Service photo
2) Additional publications have documented pests’ impacts – although I remain doubtful that they have increased decision-makers’ willingness to prioritize forest pests. Among these publications are the huge overview of invasive species published last spring (Polandet al.) and the regional overview of pests and invasive plants in the West (Barrettet al.).
3) There have been new efforts to improve prediction of various pests’ probable virulence (see recent blogs and here.
4) Attention is growing to the importance of protecting forest health as a vital tool in combatting climate change — see Feiet al., Quirionet al., and IUCN. We will have to wait to see whether this approach will succeed in raising the priority given to non-native pests by decision-makers and influential stakeholders.
Rep. Peter Welch
5) Some politicians are responding to forest pest crises – In the US House, Peter Welch (D-VT) is the lead sponsor of H.R. 1389. He has been joined – so far – by eight cosponsors — Rep. Kuster (D-NH), Pappas (D-NH), Stefanik (R-NY), Fitzpatrick (R-PA), Thompson (D-CA), Ross (D-NC), Pingree (D-ME), and Delgado (D-NY). This bill would fund research into, and application of, host resistance! Also, it would make APHIS’ access to emergency funds easier. Furthermore, it calls for a study of ways to raise forest pests’ priority – thus partially responding to the proposal by me and others (Bonello et al. 2020; full reference at end of blog) to create federal Centers for Forest Pest Control and Prevention.
This year the Congress will begin work on the next Farm Bill – might these ideas be incorporated into that legislation?
What Else Must Be Done
My work is guided by three premises:
1) Robust federal leadership is crucial:
The Constitution gives primacy to federal agencies in managing imports and interstate trade.
Only a consistent approach can protect trees (and other plants) from non-native pests that spread across state lines.
Federal agencies have more resources than state agencies individually or in likely collective efforts – even after decades of budget and staffing cuts.
2) 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 been neither adequate nor stable.
3) Programs’ effectiveness needs to be measured. Measurement must focus on outcomes, not just effort (see National Environmental Coalition on Invasive Species’ vision document).
Preventing New Introductions – Challenges and Solutions
We cannot prevent damaging new introductions without addressing two specific challenges.
1) Wood packaging continues to pose a threat despite past international and national efforts. As documented in my recent blogs, the numbers of shipping containers – presumably with wood packaging – are rising. Since 2010, CBP has detected nearly 33,000 shipments in violation of ISPM#15. The numbers of violations are down in the most recent years. However, a high proportion of pest-infested wood continues to bear the ISPM#15 mark. So, ISPM#15 is not as effective as it needs to be.
We at CISP hope that by mid-2022, a new analysis of the current proportion of wood packaging harboring pests will be available. Plus there are at least two collaborative efforts aimed at increasing industry efforts to find solutions – The Nature Conservancy with the National Wooden Pallet and Container Association; and the Cary Institute with an informal consortium of importers using wooden dunnage.
2) Imports of living plants (“plants for planting”) are less well studied so the situation is difficult to assess. However, we know this is a pathway that has often spread pests into and within the US. There have been significant declines in overall numbers of incoming shipments, but available information doesn’t tell us which types of plants – woody vs. herbaceous, plant vs. tissue culture, etc. – have decreased.
APHIS said, in a report to Congress (reference at end of blog), that introductions have been curbed – but neither that report nor other data shows me that is true.
Scientists are making efforts to improve risk assessments by reducing the number of organisms for which no information is available on their probable impacts (the “unknown unknowns”).
Solving Issues of Prevention
While I have repeatedly proposed radical revisions to the international phytosanitary agreements (WTO SPS & IPPC) that preclude prevention of unknown unknowns (see Fading Forests II and blog), I have also endorsed measures aimed at achieving incremental improvements in preventing introductions, curtailing spread, and promoting recovery of the affected host species.
The more radical suggestions focus on: 1) revising the US Plant Protection Act to give higher priority to preventing pests introductions than to facilitating free trade (FF II Chapter 3); 2) APHIS explicitly stating that its goal is to achieve a specific, high level of protection (FF II Chapter 3); 3) APHIS using its authority under the NAPPRA program to prohibit imports of all plants belonging to the 150 genera of “woody” plants that North America shares with Europe or Asia; 4) APHIS prohibiting use of packaging made from solid wood by countries and exporters that have a record of frequent violations of ISPM#15 in the 16 years since its implementation.
Another action leading to stronger programs would be for APHIS to facilitate outside analysis of its programs and policies to ensure the agency is applying the most effective strategies (Lovett et al. 2016). The pending Haack report is an encouraging example.
I have also suggested that APHIS broaden its risk assessments so that they cover wider categories of risk, such as all pests that might be associated with bare-root woody plants from a particular region. Such an approach could speed up analyses of the many pathways of introduction and prompt their regulation.
Also, APHIS could use certain existing programs more aggressively. I have in mind pre-clearance partnerships and Critical Control Point integrated pest management programs. APHIS should also clarify the extent to which these programs are being applied to the shipments most likely to transport pests that threaten our mainland forests, i.e. imports of woody plants belonging to genera from temperate climates. APHIS should promote more sentinel plant programs. Regarding wood packaging, APHIS could follow the lead of CBP by penalizing importers for each shipment containing noncompliant SWPM.
Getting APHIS to prioritize pest prevention over free trade in general, or in current trade agreements, is a heavy lift. At the very least, the agency should ensure that the U.S. prioritize invasive species prevention in negotiations with trading partners and in developing international trade-related agreements. I borrow here from the recent report on Canadian invasive species efforts. (I complained about APHIS’ failure to even raise invasive species issues during negotiation of a recent agricultural trade agreement with China.)
Solving Issues of Spreading Pests
The absence of an effective system to prevent a pest’s spread within the U.S. is the most glaring gap in the so-called federal “safeguarding system”. Yet this gap is rarely discussed by anyone – officials or stakeholders. APHIS quarantines are the best answer – although they are not always as efficacious as needed – witness the spread of EAB and persistence of nursery outbreaks of the SOD pathogen.
areas at risk to goldspotted oak borer
APHIS and the states continue to avoid establishing official programs targetting bioinvaders expected to be difficult to control or that don’t affect agricultural interests. Example include laurel wilt, and two boring beetles in southern California – goldspotted oak borer, Kuroshio shot hole borer and polyphagous shot hole borer and their associated fungi.
One step toward limiting pests’ spread would come from strengthening APHIS’ mandate in legislation, as suggested above. A second, complementary action would be for states to adopt quarantines and regulations more aggressively. For this to happen, APHIS would need to revise its policies on the “special needs exemption” [7 U.S.C. 7756]. Then states could adopt more stringent regulations to prevent introduction of APHIS-designated quarantine pests (Fading Forests III Chapt 3).
Finally, APHIS should not drop regulating difficult-to-control species – e.g., EAB. There are repercussions.
APHIS’ dropping EAB has not only reduced efforts to prevent the beetle’s spread to vulnerable parts of the West. It has also left states to come up with a coherent approach to regulating firewood; they are struggling to do so.
Considering interstate movement of pests via the nursery trade, the Systems Approach to Nursery Certification (SANC) program) is voluntary and was never intended to include all nurseries. Twenty-five nurseries were listed on the program’s website as of March 2020. It is not clear how many nurseries are participating now. The program ended its “pilot” phase and “went live” in January 2021. Furthermore, the program has been more than 20 years in development, so it cannot be considered a rapid response to a pressing problem.
Solving Issues of Recovery and Restoration via Resistance Breeding
I endorse the findings of two USFS scientists, Sniezko and Koch citations. They have documented the success of breeding programs when they are supported by expert staff and reliable funding, and have access to appropriate facilities. The principle example of such a facility is the Dorena Genetic Resource Center in Oregon. Regional consortia, e.g., Great Lakes Basin Forest Health Collaborative and Whitebark Pine Ecosystem Foundation are trying to overcome gaps in the system. I applaud the growing engagement of stakeholders, academic experts, and consortia. Questions remain, though, about how to ensure that these programs’ approaches and results are integrated into government programs.
resistant and vulnerable ash seedlings; photo courtesy of Jennifer Koch, USFS
In Bonello et al., I and others call for initiating resistance breeding programs early in an invasion. Often other management approaches, e.g., targetting the damaging pest or manipulating the environment, will not succeed. Therefore the most promising point of intervention is often with by breeding new or better resistance in the host. This proposal differs slightly from my suggestion in the “30 years – solutions” blog, when I suggested that USFS convene a workshop to develop consensus on breeding program’s priorities and structure early after a pest’s introduction.
Funding Shortfalls
I have complained regularly in my publications (Fading Forests reports) and blogs about inadequate funding for APHIS Plant Protection program and USFS Forest Health Protection and Research programs. Clearly the USDA Plant Pest and Disease Management and Disaster Program has supported much useful work. However, its short-term grants cannot substitute for stable, long-term funding. In recent years, APHIS has held back $14 – $15 million each year from this program to respond to plant health emergencies. (See APHIS program reports for FYs 20 and 21.) This decision might be the best solution we are likely to get to resolve APHIS’ need for emergency funds. If we think it is, we might drop §2 of H.R. 1389.
Expanding Engagement of Stakeholders
Americans expect a broad set of actors to protect our forests. However, these groups have not pressed decision-makers to fix the widely acknowledged problems: inadequate resources – especially for long-term solutions — and weak and tardy phytosanitary measures. Employees of federal and state agencies understand these issues but are restricted from outright advocacy. Where are the professional and scientific associations, representatives of the wood products industry, forest landowners, environmental NGOs and their funders, plus urban tree advocates – who could each play an important role? The Entomological Society’s new “Challenge” is a welcome development and one that others could copy.
SOURCES
Bonello, P., Campbell, F.T., Cipollini, D., Conrad, A.O., Farinas, C., Gandhi, K.J.K., Hain, F.P., Parry, D., Showalter, D.N, Villari, C. and Wallin, K.F. (2020) Invasive Tree Pests Devastate Ecosystems—A Proposed New Response Framework. Front. For. Glob. Change 3:2. doi: 10.3389/ffgc.2020.00002
Green, S., D.E.L. Cooke, M. Dunn, L. Barwell, B. Purse, D.S. Chapman, G. Valatin, A. Schlenzig, J. Barbrook, T. Pettitt, C. Price, A. Pérez-Sierra, D. Frederickson-Matika, L. Pritchard, P. Thorpe, P.J.A. Cock, E. Randall, B. Keillor and M. Marzano. 2021. PHYTO-THREATS: Addressing Threats to UK Forests and Woodlands from Phytophthora; Identifying Risks of Spread in Trade and Methods for Mitigation. Forests 2021, 12, 1617 https://doi.org/10.3390/f12121617ý
Krishnankutty, S., H. Nadel, A.M. Taylor, M.C. Wiemann, Y. Wu, S.W. Lingafelter, S.W. Myers, and A.M. Ray. 2020. Identification of Tree Genera Used in the Construction of Solid Wood-Packaging Materials That Arrived at U.S. Ports Infested With Live Wood-Boring Insects. Journal of Economic Entomology 2020, 1 – 12
Liebhold, A.M., E.G. Brockerhoff, L.J. Garrett, J.L. Parke, and K.O. Britton. 2012. Live plant imports: the major pathway for forest insect and pathogen invasions of the US. Front. Ecol. Environ. 2012; 10(3):135-143
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
Mech, A.M., K.A. Thomas, T.D. Marsico, D.A. Herms, C.R. Allen, M.P. Ayres, K.J. K. Gandhi, J. Gurevitch, N.P. Havill, R.A. Hufbauer, A.M. Liebhold, K.F. Raffa, A.N. Schulz, D.R. Uden, & P.C. Tobin. 2019. Evolutionary history predicts high-impact invasions by herbivorous insects. Ecol Evol. 2019 Nov; 9(21): 12216–12230.
Poland, T.M., Patel-Weynand, T., Finch, D., Miniat, C. F., and Lopez, V. (Eds) (2019), Invasive Spp in Forests and Grasslands of the US: A Comprehensive Science Synthesis for the US 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 invasive pests requires new trade regulations. Front Ecol Environ 2014; 12(8): 457–465
Schulz, A.N., A.M. Mech, M.P. Ayres, K. J. K. Gandhi, N.P. Havill, D.A. Herms, A.M. Hoover, R.A. Hufbauer, A.M. Liebhold, T.D. Marsico, K.F. Raffa, P.C. Tobin, D.R. Uden, K.A. Thomas. 2021. Predicting non-native insect impact: focusing on the trees to see the forest. Biological Invasions.
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.
For a detailed discussion of the policies and practices that have allowed these pests to enter and spread – and that do not promote effective restoration strategies – review the Fading Forests report at http://treeimprovement.utk.edu/FadingForests.htm
Posted by Scott J. Cameron, former Acting Assistant Secretary for Policy Management and Budget , US Department of the Interior
locations in Hawaii Volcanoes National Park where ohia trees were infected by rapid ohia death pathogen in 2017
In 2019 Congress passed the John D. Dingell, Jr. Conservation, Management, and Recreation Act. Among other things, it directed the Department of the Interior to “develop a strategic plan that will achieve, to the maximum extent practicable, a substantive annual net reduction of invasive species population or infested acreage on land or water managed by the Secretary.” This provision triggered a year-long process of public involvement and inter-bureau coordination. The result was a plan published in January 2021. It represents the first attempt by Interior at a Department-wide multi-taxa, multi-year approach to invasive species. It has the potential to spur integration of invasive species work across the Department’s many bureaus and to focus each bureau’s efforts on a set of common goals, strategies, and performance metrics.
While Congress’ language is open-ended, any planning exercise is constrained by the most recent President’s budget and existing law. It is up to those of us who are not, or at least no longer, executive branch employees to advocate for plans unbound by those constraints.
In that spirit, I offer eight recommendations to improve invasive species management. Four are within existing authorities; four more are outside the current budgetary and statutory framework. Many more ideas are without a doubt worth pursuing.
Opuntia (prickly pear) cactus – common plant in western National parks and on Bureau of Land Management lands; under threat by cactus moth
First, within existing funding and legal authorities, the Department has unfinished business that it can act on now.
Secure approval of the package of categorical exclusions under the National Environmental Policy Act (NEPA) — now awaiting approval by the President’s Council on Environmental Quality (CEQ). Over many years agencies have documented how invasive species control improves, rather than harms, the environment. Absent an applicable NEPA categorical exclusion approved by CEQ, though, each such action needs to run the time- and money-consuming gauntlet of NEPA compliance. In the meantime, the invasive plants germinate, the invasive animals reproduce, and what might have been a localized and inexpensive problem has expanded geographically and in terms of cost and complexity. In the Fall of 2020 Interior submitted hundreds of pages of documentation on numerous practices proven to control invasive species without harming the environment. Due to time and staffing constraints at CEQ, these categorical exclusions still await action. Interior and CEQ should take prompt steps to finish them.
Allocate to the US Geological Survey at least $10 million of the roughly $90 million remaining available to the Secretary in CARES Act appropriations for research on invasive zoonotic diseases. These are diseases like COVID-19 and West Nile virus that can move from one species to another. Many zoonotic diseases fit the definition of invasive species, since they are not native to the United States and endanger human health. In the case of COVID-19 funding is available to the Secretary of the Interior, without need for further Congressional action, from funds appropriated by the CARES Act. The availability of these funds will expire at the end of September 2021, so Interior should provide this research funding to USGS as soon as possible.
Join the existing Memorandum of Understanding between the Western Governors Association (WGA) and the US Department of Agriculture’s Forest Service. These groups have established “a framework to allow the U.S. Forest Service (USFS) and WGA to work collaboratively to accomplish mutual goals, further common interests, and effectively respond to the increasing suite of challenges facing western landscapes.” This provides a forum to improve coordination between the States and the federal government on the management of invasive species, and Interior needs to be part of that team.
Interior should work with USDA to accelerate and intensify efforts to systematically improve coordination between the interagency Wildland Fire Leadership Council and the interagency National Invasive Species Council. Both Councils have member agencies that practice vegetation management using similar tools and techniques, although for different purposes. The two Councils should identify a select number of initiatives in FY21 where their efforts would benefit both wildland fire management and invasive plant management .
swamp bay trees in Everglades National Park killed by laurel wilt; photo by Tony Pernas
Four steps to implement the strategic plan outside the scope of current law and the President’s Fiscal Year 2021 budget. I offer the following:
Improve implementation of the Lacey Act program to list injurious species. There are both legislative and administrative elements to this proposal.
In a federal District Court decision on May 19, 2015, on a lawsuit filed by the Association of Reptile Keepers, the Court undid the longstanding Fish and Wildlife Service policy that the Lacey Act allowed FWS to ban interstate transport of injurious species. On April 7, 2017, the D.C. Circuit Court of Appeals upheld the District Court’s view. These rulings mean that FWS authority only applies to international commerce. Unfortunately, the court’s interpretation of the law and legislative history are reasonable, so Congress needs to amend the law to make it clear that FWS is explicitly authorized to regulate interstate commerce in injurious species. The Department of the Interior should work with the Department of Justice and the Office of Management and Budget to develop the necessary bill language and submit it to Congress.
At the same time, the FWS injurious species listing process is notoriously slow, even causing Congress to occasionally list species legislatively. The fact that these legislative initiatives have sometimes been promoted by Members of Congress who normally are opposed to more federal regulation signals just how awkward the current FWS process is. Thus there might well be strong bipartisan support to amend the Lacey Act on the interstate commerce matter. Acting on its own authority, FWS should procure an independent third party review of the injurious species listing process and ask the contractor to make suggestions for “business process reengineering” to improve and streamline current practices, along with evaluating whether higher funding or new technology is needed.
The Bureau of Reclamation, Department of the Interior, and the Office of Management and Budget should develop legislative language to submit to Congress for the 2022 Water Resources Development Act, that explicitly authorizes an aquatic nuisance species program in the Bureau of Reclamation. It could parallel the relatively new authority enjoyed by the Army Corps of Engineers and mandate increased coordination between the two water agencies.
Any climate change legislation pursued by Congress and the Administration should include provisions for addressing invasive species. Climate change will make some North American habitats more suitable for foreign organisms, as cold-intolerant species might be able to survive in more northern latitudes in the U.S. than previously was the case. Second, the disruptive effect of climate change on North American ecosystem structure and trophic relationships at any latitude will make those ecosystems more vulnerable to invasion. Finally, the spread of invasive species may in and of itself exacerbate climate change, such as through the increased carbon dioxide emissions from rangeland wildfires aggravated by the dominance of invasive cheatgrass.
The Senate Committee on Environment and Public Works and the House Natural Resources Committee should each hold oversight hearings on how best to help state and local governments detect and respond to new invasive species that are not within the statutory purview of USDA/APHIS. This is a complex topic, important for both ecological and financial reasons. Over the years several attempts to address it have failed. A thoughtful review by Congress and the Administration, which perhaps would lead to passage of new statutory authority and funding, is worth exploring.
The Author:
Scott Cameron recently left the federal government, where he had served as Acting Assistant Secretary for Policy, Management and Budget at the U.S. Department of the Interior. In that capacity he oversaw Department-wide budget, invasive species, natural resource damage assessment and restoration, environmental compliance and numerous administrative functions of this $14 billion agency with 65,000 employees. Previously, Scott held other civil service job (e.g., at the White House Office of Management and Budget) & political appointments in the federal government, on the staff of the Governor of California, and on Congressional staffs. While not in government, Scott led formation of the Reduce Risk from Invasive Species Coalition.
CISP welcomes 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.
Further information on the plant pests mentioned in the photo captions can be obtained at www.dontmovefirewood.org; click the “invasive species” button.
spotted lanternfly; photograph by Holly Ragusa, Pennsylvania Department of Agriculture
Since Fiscal Year (FY)2009, APHIS has had access to a program that has permanent funding, not subject to the vagaries of annual budgeting and appropriations. The Plant Pest and Disease Management and Disaster Prevention Program established by 7 U.S.C. Section 7721. The program was initially funded at $12 million for FY2009; $45 million in FY2010; $62.5 million in 2014-2017; and $75 million since FY2018.
Funds are provided under a competitive grants program to universities, states, Federal agencies, nongovernmental organizations, non-profits, and Tribal organizations “to conduct critical projects that keep U.S. crops, nurseries, and forests healthy, boost the marketability of agricultural products within the country and abroad, and help us do right and feed everyone.” [USDA press release “USDA Provides $66 Million in Fiscal Year 2019 to Protect Agriculture and Natural Resources from Plant Pests and Diseases” February 15, 2019]
By my calculation, total funding of tree pests projects during the period Fiscal Year (FY09) through FY20 was about $94 million. This represented 15.6% of nearly $600 million in total funding under the program during this period.
In the initial years, forest pest projects received about 10-12% of total funds. In later years, the proportion has been higher – e.g., 30% in FY19, 13.8% in FY20. The early years were dominated by management of the sudden oak death pathogen (SOD), Phytophthora ramorum. In FY09, SOD projects receive $7.5 million, or 8% of all tree pest funding. This funding helped set up the National Ornamental Nursery study center (NORS-DUC); later years paid for research projects on SOD management issues and nursery surveys.
In the most recent years, funding has been dominated by detection, management, and research on spotted lanternfly – which is not primarily a forest pest. Thus, in FY 19, 56.8% ($10,339,126) of $18,195,000 allocated to tree pests; in FY20, 30% ($2,606,094) of the $8,705,920 allocated to all tree pests.
The FY2019 program also provided $1,107,965 in 14 states and nationally for P. ramorum survey, diagnostics, mitigation, probability modeling, genetic analysis, and outreach (USDA press release 2019). This was appropriate considering the shipment of SOD-infected plants to nurseries in 18 states in spring 2019.
Current Year Funding
APHIS has released the list of projects funded under the Plant Protection Act Section 7721 in FY2021. Link to website APHIS funded 354 projects in 49 states, Guam, Puerto Rico and the District of Columbia, at a total cost of $63.225 million. APHIS is retaining ~ $14 million to allow responses to pest and plant health emergencies. Total funding for forest pests – by my calculation – was $8,715,046 (13.7% of the total).
My analysis finds that in FY21, 13 states had no funded projects that applied to tree pests: Arizona, Colorado, District of Columbia, Guam, Hawaii, Idaho, Nebraska, New Jersey, New Mexico, North Dakota, Rhode Island, South Dakota, and Utah.
Most commonly funded projects:
Surveys and other efforts addressing wood borers: 37 projects, including
Thousand cankers disease: 4 (all surveys)
Emerald ash borer: 6 projects (surveys and management, including biocontrol)
Asian longhorned beetle: 3, of which 2 are outreach
Laurel wilt disease: 1 project
Detection tools for wood-borers, including citrus longhorned beetle, Sirexnoctilio, Agrilus biguttatus, and Australian Cerambycids
Phytophthora ramorum: 20 projects, primarily nursery surveys but including a few management projects. The projects were in 18 states.
Surveys for Asian defoliating moths in the Lymantra genus: 15 projects
Surveys and control efforts targetting spotted lanternfly: 13 projects in 6 states. These included research conducted by the APHIS Otis laboratory in Massachusetts. The grants totaled $2,788,010, or 32% of total forest pest funding.
APHIS funded 16 outreach projects (there is some overlap with above), including three specifically mentioning firewood. The latter included principal funding for the “Don’t Move firewood” national campaign.
Other projects that I find interesting:
2 projects targetting hemlock woolly adelgid
1 targetting red palm weevil
4 projects targetting Asian giant hornet in Washington and Oregon and the APHIS Otis laboratory. California has a project relating to a wider range of hornets that was also funded in FY20.
Biocontrol of several invasive plant species in Florida – Australian pine/Casuarina, Brazilian pepper, and Ailanthus
Harrisia cactus attacked by the mealybug; photo by Yorelyz Rodríguez-Reyes
As readers of this blog know, I also care deeply about threats to our native cacti – especially flat-padded Opuntia and tubular cacti endemic to Puerto Rico. Over the 13 years of program, funded following projects for cacti:
FY11 $244,368 for efforts to develop sterile insect methodology to control cactus moth
FY17 develop biocontrol for Harissia cactus mealybug $210,000
FY 21 cactus moth biocontrol $175,659 and $352,236 for Harrisia cactus mealybug biocontrol
Clearly, having access to $75 million that is not subject to the limits imposed by Administration budget priorities or Congressional appropriations has allowed considerable freedom. The fund has allowed APHIS to support work on pests that have not been designated “quarantine pests,” e.g., walnut canker disease of walnut, the polyphagous and Kuroshio shot hole borers, hemlock woolly adelgid, and the cactus pests. The program also funded many projects targetting the spotted lanternfly (SLF) – both before and after the lanternfly became a formal APHIS program (which occurred after it was detected outside Pennsylvania). Now that SLF has been found in several states, funding has partially shifted to appropriated funds. The FY21 appropriation included an additional $4 million for management of SLF; this was incorporated in the “specialty crops” line item.
So far, there has been no funding for beech leaf disease through this program; I don’t know whether any of the people working on this disease had applied.
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.
For a detailed discussion of the policies and practices that have allowed these pests to enter and spread – and that do not promote effective restoration strategies – review the Fading Forests report at http://treeimprovement.utk.edu/FadingForests.htm
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
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.
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.
