Invasive Plants in the Forest – focus on the Northeast

control of multiflora rose

Nancy Dagli, USDI National Park Service,


Nearly two years ago I posted a blog based on a study by Christopher Oswalt and colleagues (2016; source/link provided at end of blog) using data from the national Forest Inventory and Analysis (FIA) program of the United States Forest Service to determine what proportion of American forests are invaded by non-native plants. Nationwide, 39% of forested plots sampled contained at least one invasive species. Eastern forests are second in the density of invasive plants to Hawai`i, with 46% of plots invaded by at least one plant species.

FIA sampling plots are randomly located across the country. Plots are inventoried once every 5–7 years in the eastern U.S. and once every 10 years in the western U.S. The program inventories only plots that are at least 10% stocked by trees. Phase 2 (P2) plots represent approximately 6,000 acres; Phase 3 (P3) plots represent about 96,000 acres, except in some states and National Forests where there is a regional intensification of plots. Invasive plant species are measured on a subset of the field plots – on the P2 invasive plots, invasive plants of interest are recorded; on the P3 plots, all plant species (invasive, exotic, and native) are recorded.

The US Forest Service Northern Region (Region 9) has issued a report providing details for 50 invasive plant species on plots in the 24 states of the Region. (These states reach from Maine to the Dakotas, south to Kansas, then across to Delaware.) For this report, in states where both P2 invasive and P3 data were collected, the invasives data from the P3 plots were folded into the P2 invasive plots. When there were no P2 invasive plots for a particular inventory or species, the IPS data were calculated solely from P3 plots. In addition, the taxa reported varied over time and in some cases from state to state. Finally, the inventories took place over a period of years; the most recent inventories included in the report date from 2010. Presumably, the extent and intensity of plant invasions have increased in the intervening seven years. [The report is posted here.

Given the variety of plots inventoried, changes in taxa recorded, and time lag, the report cannot provide an up-to-date and detailed picture of any one site.  However, it does allow us to get an overall picture that is more detailed than the nation-wide summary provided by Oswalt et al. 2016 and reported in Faith’s blog from spring 2016.

The report contains a wealth of data on the 50 individual species – a page for each, providing background, characteristics, distribution, monitoring data, and regulatory status in the various states. Also, there are 10 pages of summary tables. Since FIA inventories are conducted on the schedule of five to seven years, future reports based on these “[r]epeated measurements will help determine factors … associated with the presence of these species” and that the data can help “educate individuals of potential risk species”.


Our Interpretation

It is unfortunate that the USFS Southern Region has not prepared a similar report so that we could understand the extent of invasion by the individual taxa across the entire eastern deciduous forest. This is especially unfortunate because the Northern Region report found that the number of invasive plant species on a plot is higher in the southeastern portion of the Region (i.e., the states of West Virginia, Maryland, and Delaware). The arbitrary boundary between the Northern and Southern regions prevent our getting a true regional picture for the Mid-Atlantic states. The Oswalt et al. 2016 summary does allow some comparisons.

Still … we found it striking that seven of the 15 invasive plant species ranked highest in terms of proportion of plots invaded are shrub or vine species that were deliberately planted for improving wildlife habitat, horticulture, or other purposes.


Detailed Findings

The report does not state the proportion of all survey plots invaded by at least one invasive plant species for the region as a whole. Table 3 does report the proportion of plots in specific states. This varies from a high of 93% of plots in Ohio to a low of about 11% in Minnesota and New Hampshire. Several other Midwestern states also experience high levels of invasion: Iowa 81%, Indiana 79%, Illinois 72%, and Missouri 46%. Plots in Mid-Atlantic states and southern New England also are heavily invaded: West Virginia 79%, Maryland 65%, Pennsylvania 61%, Connecticut 54%, Rhode Island 51%, New York 49%, New Jersey 48%, Delaware 47%, Massachusetts 44%. In general, states in the far north have lower rates of invasion, like Minnesota and New Hampshire (above): Vermont 18%, South Dakota 15%, Michigan 14%, Maine 12%. However, North Dakota, at 29%, and Wisconsin, at 28%, differ from this generalization.

The most frequently recorded invasive plant is multiflora rose. According to the report, it is present in 39 states and five Canadian provinces. Across the region, multiflora rose is present on 16.6% of surveyed plots. It is the most common invasive plant in 10 of the 24 states of the region. It is almost ubiquitous in some states; in Ohio 85% of the plots were invaded. Oswalt reports that “roses” were the third most common invasive plants in the USFS Southern Region.

The third most frequently recorded invasive plant species is garlic mustard. It is reported to be present in 36 states and five Canadian provinces. Across the region, garlic mustard is present on 4.5% of the surveyed plots. Several states report high levels of infestation. In Ohio, garlic mustard is present on 30% of the plots; in Maryland, on 27% of the plots; in Pennsylvania, on 22% of the plots; in New Jersey, on 20%.

The fourth most frequently recorded invasive is common or European buckthorn. It is reported to be present in 34 states and eight Canadian provinces. Buckthorn is present on 4.4% of survey plots across the northeastern region – about a quarter of the plots on which multiflora rose is found. The highest proportion is in New York, where the invasive shrub is found on 16.8% of the plots.

Several bush honeysuckles rank high in the survey. Because of their close relationship and similar ecological impacts, we will discuss them together. Morrow’s honeysuckle is the fifth most commonly detected invasive plant species. This species is found on 3.8% of plots across the region. Amur honeysuckle ranks tenth; it is found on 3.1% of plots. Tatarian honeysuckle ranks sixteenth; it occurs on 1.5% of plots across the region. The hybrid showy fly, or Bell’s, honeysuckle ranks eighteenth; it occurs on 1.1% of plots. The data do not indicate whether there is much overlap in the plots invaded by the various species, so we cannot determine an overall invasion extent for bush honeysuckles – although clearly they occupy a significant proportion of the forest of the region. If there is almost no overlap, bush honeysuckles occupy 9.5% of all surveyed plots – second only to multiflora ros. During the first year of the survey, bush honeysuckles were recorded by genus – but only in four Midwestern states. In that survey, the genus was found on 6.5% of the plots surveyed.

The sixth most frequently recorded plant species is also an Asian honeysuckle – the vine Japanese honeysuckle, which is found on 3.6% of survey plots across the region. Oswalt et al. 2016 report that Japanese honeysuckle is the most common invasive plants in forests in the Southern region.

The second and seventh most frequently recorded plant species are native to parts of the region surveyed – although they have spread. These are black locust and reed canarygrass. We are confused as to how many of the reported plots actually represent invasions by these species since several states with high proportions of plots bearing black locust, for example, are in or next to the Appalachian mountains and the Ozarks, where the species is native.

The eighth and eleventh most frequently recorded invasive plant species are thistles — Canada thistle is eighth, bull thistle is eleventh. Both are found in more than 40 states and all 10 of the Canadian provinces. Each is present on approximately three percent of the plots, with concentrations in the upper Midwest.

The ninth and twelfth highest ranking invasive plant species in the region are additional shrubs which were deliberately planted for various purposes. Autumn olive ranks ninth; it occurs on approximately three percent of plots across the region. It is particularly dense in West Virginia, where it occurs on one fifth of all plots surveyed. Japanese barberry ranks 12th. It occurs on 2.4% of the plots across the region. In Connecticut, barberry is found on one-third of the plots.

The thirteenth most common species is common burdock – found on 2.2% of the plots. Again, the highest densities are found on forest plots in the upper Midwest along the edge of the prairie.

The fourteenth most commonly reported species is Nepalese browntop or Japanese stiltgrass. Stiltgrass has spread without much artificial assistance. Although stiltgrass is more common in the Southeast (outside the study region), it still occupies 2.1% of surveyed plots in the Northern region. Owald et al. 2016 report that stiltgrass is the fifth most common invasive plant in the Southern region.

Additional Studies Needed

  • The USFS Northern and Southern regions should coordinate their reports so that at least some use compatible methods and combine their findings so can see the picture for the entire Eastern forest.
  • USFS scientists should collaborate with other programs that map invasive plants – e.g., EDDMapS, the National Park Service, and Invasive Plant Councils – in both selection of species to target and developing an overall picture. As noted in Faith’s earlier blog, the Mid-Atlantic Invasive Plant Council has a list of 285 invasive plants in the region. Does the subset of 50 species selected for the FIA inventories provide an accurate picture of plant invasions in this sub-region?
  • Scientists should cooperate to evaluate the relative importance of propagule pressure v. forest fragmentation as factors in facilitating invasions. Their relative roles probably vary by species, receiving forest, etc.
  • We welcome the attention to invasions of interior forests – a topic previously neglected. Nevertheless, forest “edges” are also important ecologically – and – based on what we see in the Mid-Atlantic region – are even more heavily invaded. What impact does a wall of vines have on wildlife and plant species that evolved to live in area of greater light and temperature variation of trees, shrubs, herbaceous species that made up the edge before invasion?

Actions to Counter Plant Invasions

  • Those who sell plants for any use – ornamental horticulture, ground cover, livestock forage, soil amelioration, wildlife habitat management, biofuels – should commit to avoiding species that are known or suspected to be invasive in the region.
  • Voluntary efforts to limit sales of invasive plants have fallen by the wayside. The various Invasive Plant Councils should work with industry groups and others to renew this effort. Also, the Councils should propose a joint list of additional plants for APHIS regulation under NAPPRA (see below).
  • Those who buy plants for these various uses should make a similar commitment – especially large, institutional buyers like state highway departments.
  • Concerned citizens should lobby their state governments and the Congress to fund “noxious weed” programs and to ensure that these programs include plant species that threaten natural areas, not just weeds of agriculture.
  • Concerned citizens should lobby the Congress to increase funding for federal agencies’ invasive plant control programs, especially those addressing natural areas, and especially in Hawai’i and the eastern United States. Also, the U.S. Department of Agriculture needs to adopt procedures that enable APHIS to act more quickly to curtail introduction and human-assisted spread of invasive plants.

In June 2017, APHIS finalized its May 2013 proposal to restrict importation of 22 potentially invasive plant species – as provide by its NAPPRA program. (For a description of this program and the recent action, visit Faith’s blog here. APHIS should be empowered to use this program more aggressively to list additional plant taxa that appear likely to be invasive.


Christopher M. Oswalt, Songlin Fei, Qinfeng Guo, Basil V. Iannone III, Sonja N. Oswalt, Bryan C. Pijanowski, Kevin M. Potter 2016. A subcontinental view of forest plant invasions. NeoBiota. 24: 49-54

posted by Faith Campbell & guest Jil Swearingen

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.


Worldwide Study Confirms ISPM#15 is not Protecting Forests – What Do We Do Now About Pests in Wood Packaging?


You know that the continuing pest risk associated with imports of wood packaging is among my biggest concerns. See, for example, fact sheets here and blogs here and here.

A new book about the family Cerambycidae (edited by Wang 2017; reference at end of blog) confirms that longhorned beetles continue to be introduced to many countries via this pathway, more than a decade after widespread implementation of the international standard governing wood packaging (ISPM#15). Furthermore, data from several countries confirm that China continues to fall short … but that problems are more widespread.

The Wang book finds that 16 outbreaks of the Asian longhorned beetle (ALB) were detected between 2012 and 2015.

Unless otherwise noted, the information provided here comes largely from the book’s chapter on biosecurity coauthored by Dominic Eyre and Robert A. Haack (see link below). Opinions stated are mine, unless specified otherwise.

In some cases – which I will note – further details are from my earlier posts.

While I think the risk of introduction of highly damaging pests via the wood packaging pathway is well documented in Wang (2017) and other publications, no one can truly quantify this risk because of shortcomings in countries’ data. Available data come primarily from countries’ records of pest “interceptions” – usually at points of entry.  However, interception data are inadequate to conclusively establish the lack of a threat for a particular trade or to provide a fair comparison of the relative threat of particular trades. Most interception databases have the following shortcomings (Eyre and Haack are summarizing points made by a third scientist – Lee Humble – in an earlier article):

(1) interception databases are not based on random sampling, which is necessary to measure the “approach” or “infestation” rate;

(2) inspections which find no pests are not recorded, so we cannot know what proportion of incoming shipments are infested;

(3) once inspectors have discovered a quarantine pest in a shipment, the consignments may be destroyed without further inspection, and thus other exotic organisms can be missed;

(4) only a small percentage of individual shipments are inspected; and

(5) organisms often are not identified to species due to difficulty of identifying larvae.


(1) trade volumes and sources can change rapidly;

(2) the number of consignments inspected varies from year to year in response to national and regional plant health and wider government priorities;

(3) the method and intensity of quarantine inspections can vary within and among countries and as well as over time; and

(4) different proportions of consignments from different trades can be inspected, reflecting the perceived quarantine risks of each trade.

Still, scientists try to analyze the available data because propagule pressure may be the most important factor in determining whether an exotic pest becomes established.

What have they found?

Data from both the United States and Europe document that problems of non-compliance continue in recent years – more than a decade after adoption of ISPM#15.

United States:

  • Since APHIS interception records began being computerized in 1985, Cerambycidae have been among the most frequently intercepted insect families associated with wood products and packaging. The top five countries for infested shipments during the period 1984 – 2008 were China, Italy, Mexico, Turkey and Spain. A country’s rank is linked in part to import volumes – which are very high for China, Canada, and Mexico. Because the  U.S. inspects very limited quantities of wood packaging from Canada, its absence from the top five may be misleading [discussed in my blog from February, here.

Another factor explaining these countries’ rankings is the continued – in fact increasing! – presence of pests in wood packaging accompanying imports of tile and quarry products (e.g., marble, slate). Many of these imports are from Italy, Spain, and Mexico. Interceptions on these imports increased significantly from the mid-1990s to 2008. The increase in these interceptions is most alarming because it shows USDA leaders have not yet taken effective action to curtail this risk, despite its being evident since record-keeping began.


  • Over the period Fiscal Years 2010 through 2016, the U.S. Bureau of Customs and Border Protection has detected nearly 5,000 consignments in which cases the wood packaging harbored a pest in a regulated taxonomic group. APHIS experts identified 2,500 insects taken from wood packaging during this period; a quarter were Cerambycids. A second APHIS analysis of a subset of the wood packaging-associated insects found examples from 39 countries, including 212 shipments from Europe; 130 shipments from Asia; and 341 shipments from the Americas – almost exclusively Mexico. [These detections are discussed in my blog from February, here.


Europe has had a similar experience.

  • Interception records included in EUROPHYT show 306 Cerambycidae interceptions on wood packaging over the period 1998 – 2013. The number of interceptions recorded in 2012 and 2013 are double those of all previous years. Each year, the majority are on wood packaging from China.
  • Most interceptions of ALB (distinct from detections of establishments) have occurred after the shipment cleared border inspection procedures, e.g., in warehouses.
  • As with the U.S., while the majority of non-compliant shipments are from China, the problem is worldwide: Europe has also found various species of longhorned beetles in wood packaging from various European countries (inside and outside the European Union), other Asian countries, Africa, Australasia, and the Americas.
  • Austria inspected 451 consignments of stone imports received April 1, 2013 – April 14, 2014. Forty-four consignments (9.8%) were found to be out of compliance with ISPM#15. Live Cerambycidae were found in 38 consignments (8%), including ALB. This finding confirms the widespread awareness that stone imports rank high for non-compliant wood packaging.


Regulatory Authorities’ Response (or lack thereof)


  • Since March 31, 2013, the European Union has required inspection of 90% of consignments of slate, marble, and granite and 15% of consignments of two other categories of stone imports.

CBP agriculture specialists in Laredo, Texas, examine a wooden pallet for signs of insect infestation. [Note presence of an apparent ISPM stamp on the side of the pallet] Photo by Rick Pauza
United States

  • As noted by Haack et al. (2014) (reference below), as of 2009, approximately 13,000 containers harboring pests probably enter the U.S. each year. That is 35 potential pest arrivals each day. [This issue is also discussed in the fact sheet and blogs here and here.
  • The United States has not specified an obligatory inspection rate for such high-risk imports as stone and tile. Instead, it relies on Customs and Border Protection to target import shipments suspected of being out of compliance based on past performance of importers, suppliers, and types of imports.
  • Several relevant issues are discussed in the blog in February 2017 (second blog linked to above). First, I noted that the U.S. Department of Homeland Security Bureau of Customs and Border Protection – over the seven-year period Fiscal Years 2010 through 2016 – has detected nearly 5,000 cases of wood packaging harboring a pest in a regulated taxonomic group. Comparing the estimate by Haack et al. 2014 with the CBP data indicates that Customs is detecting about 6% of all pest-infested shipments.
  • Furthermore, about 26% of infested wood pieces detected by CBP were found in wood that was marked as having been treated according to ISPM#15 requirements. What does this mean? Fraud? Accidental misapplication of the treatments? Or are the treatments less effective than hoped? What are USDA and other responsible agencies doing to clarify the causes?
  • CBP staff reported that only about 30 import shipments (out of nearly 21,000 shipments found to be in violation of ISPM#15 requirements) have received a financial penalty. How can USDA and Customs officials justify this failure to enforce the regulations?



What Can Be Done to Close Down the Wood Packaging Pathway


I suggest that our goal should be to hold foreign suppliers responsible for complying with ISPM#15. One approach is to penalize violators. APHIS and Customs might

  • Prohibit imports in packaging made from solid wood (boards, 4 x 4s, etc.) from foreign suppliers which have a record of repeated violations over the 11 years ISPM#15 has been in effect (17 years for exporters from Hong Kong & mainland China). Officials should allow continued imports from those same suppliers as long as they are contained in other types of packaging materials, including plastic, metals, or fiberboards.
  • Fine an importer for each new shipment found to be out of compliance with ISPM#15 in cases when the foreign supplier of that shipment has a record of repeated violations.


There would need to be a severe penalty to deter foreign suppliers from simply changing their names or taking other steps to escape being associated with their violation record.


At the same time, the agencies should work with non-governmental organizations and importers to promote creation of an industry certification program that would recognize and reward importers who have voluntarily undertaken actions aimed at voluntarily exceeding ISPM#15 requirements so as to provide a higher level of protection against invasive species that would otherwise potentially be introduced into the United States.


What You Can Do

  • Tell your member of Congress and Senators that you are worried that our trees are still being put at risk by insects arriving in wood packaging. Ask them to urge the USDA Secretary Sonny Perdue to take the actions outlined above in order to curtail introductions of additional tree-killing pests.
  • Talk to your friends and neighbors about the threat to our trees. Ask them to join you in communicating these concerns to their Congressional representatives and Senators.
  • Write letters to the editors of your local newspaper or TV news station.


Use your knowledge about pests threatening trees in your state or locality in your communications!


Other Introduction Pathways for Cerambycids

tree removals in Tukwilla, WA to eradicate citrus longhorned beetle; photo by Washington State Department of Agriculture

Plants for planting

Other studies have confirmed that importation of living plants (called by regulators “plants for planting”) is a high-risk pathway for introducing tree-killing pests. See the Eyre and Haack chapter for a summary.

This is as true for highly damaging Cerambycids as for other types of plant pests. One of the most damaging is the citrus longhorned beetle (CLB) (Anoplophora chinensis). CLB [] poses an even greater threat to North American forests than ALB – it has a wider host range and climate-matching models show that it could establish across most of the United States. CLB were detected in a nursery in Tukwilla, Washington, in 2001; the pest was eradicated. Nine CLB outbreaks have been detected in Europe; three are considered eradicated (Eyre & Haack 2017).

Eyre and Haack (2017) report that in Europe of the 455 Cerambycidae intercepted over the period 1998 – 2013, 54 were on imported in living plants. These included probably 49 citrus longhorned beetle (CLB). Most were detected primarily on maple nursery stock that originated China (32), with smaller numbers from other countries, including Netherlands (8), and Italy (where CLB has been established).

New Zealand has intercepted 74 CLB on plants for planting over the 28 year period 1980 – 2008.  One third of this total was intercepted in 2008.


Authorities’ Responses (or lack thereof)


  • Since 2012, the European Union has required that 10% of CLB host plants imported into the European Union should be destructively sampled (that is, dissected to see whether insects are present internally).
  • This requirement supplements a broader requirement that plants for planting be treated as a high risk commodity. Member states are required to inspect all incoming P4P consignments. This requirement is, however, undermined by much more lenient requirements regarding movement of plants among EU member states – some genera are not regulated … others are controlled by Plant Passports – an industry-led scheme.  [For more on this issue, see my blog from October 2016 here.


United States

  • APHIS issued a Federal order tightly restricting imports of CLB hosts from Europe in 2013 – four years after a CLB outbreak was detected in a part of the Netherlands which is a center for the production of hardy ornamental nursery stock for European and probably American markets.
  • APHIS proposed to revise its overall plant importation regulations (the “Q-37 regulations) to rely more on integrated management by the exporting nurseries in contrast to port inspections. This rulemaking has stalled. [See my blog about this here.]


Finished Wood Products

While no country is keeping comprehensive records, finished wood products have transported longhorned beetles.  Eyre and Haack (2017) concluded that upholstered furniture presents one of the highest risk among the finished wood products – partly because imports are rising rapidly, partly because insect-damaged wood can be hidden under the upholstery. New Zealand found that some Asian manufacturers place good quality wood on visible surfaces and poor quality timber (insect damaged and bark covered) in internal sections. Officials inspected 49 couches and found that 30 had wood with bark, 19 had insect contaminants, and 32 had visible insect damage. Fungal samples were isolated from 11 of the couches. They found 4 longhorned beetles.



Wang, Q. (Ed.). 2017. Cerambycidae of the world: biology and pest management.  Boca Raton, FL: CRC Press

The chapter on biosecurity is available here:

A chapter on Cerambycid impacts in urban and rural forests is available here:


We welcome comments that supplement or correct factual information, suggest new approaches, or promote thoughtful consideration. We post comments that disagree with us — but not those we judge to be not civil or inflammatory.


Posted by Faith Campbell

Feral hog eradication – making progress by doing it the right way

large_hog_damage (MO)

feral hogs in Missouri

As I wrote in my blog of March 2016, introduced wild hogs (Sus scrofa) threaten ecosystems across the continent and on islands ranging from Hawai`i to the Caribbean.

According to an environment impact statement prepared by APHIS (see reference below), these highly adaptable, prolific, large and powerful animals cause immense damage by rooting for plant parts and invertebrates in the soil, and by wallowing to cool themselves and fend off biting insects. Pigs may root to depths of three feet below the surface. Wallows are commonly located in or adjacent to riparian or bottomland habitats. Feral hogs out-compete other animals for hard mast and also consume algae, fungi, soil invertebrates, worms, crustaceans, and bird and reptile eggs. They even feed on small vertebrate animals.

Rising feral hog populations and spread to new areas has raised concern. insert map  According to John J. Mayer (reference below), the number of states with established wild boar populations is now 37. They might number as many as 11.3 million. Texas has the largest numbers, 30 to 41% of the U.S. total. Other states with high numbers are Alabama, Arkansas, California, Florida, Georgia, Louisiana, Mississippi, Oklahoma, and South Carolina.


Poison them?

One proposed response was to poison the hogs using the anticoagulant drug Warfarin – which is widely used as a rodent poison. The U.S. Environmental Protection Agency (EPA) approved the use of warfarin as a bait – Kaput® Feral Hog Bait – in January 2017 after only 16 months of review – an unprecedented brief period for a toxin. Many expressed concern, especially about possible poisoning of non-target wildlife. The National Environmental Coalition on Invasive Species was one of several groups to ask EPA to reconsider.  Principal concerns raised: black bears and other wildlife could open the bait dispenser; spilled bait could be eaten by a wide variety of wildlife; scavengers could be exposed when they feed on the carcasses of poisoned pigs; hunters could also be exposed to contaminated meat. Several states considering use of the bait – including Louisiana and Texas – decided to reconsider. The Arkansas Game and Fish Commission also asked the state Plant Board to take care pending additional study of the secondary effects.

Missouri Program Expands

Meanwhile, Missouri is finding success with its aggressive and scientifically-based program, which began  years ago in response to growing public concern about hog damage. As I noted in my earlier blog, in 2016, the Missouri Conservation Commission prohibited hunting of feral hogs on lands owned, leased, or managed by the Missouri Department of Conservation. Missouri took this action because hunting does not significantly reduce feral hog populations. Instead, it causes the animals to disperse – making them even more difficult to control. (Missouri has extensive material on feral hogs posted here  .

The Missouri Department of Conservation is working with several partners – including other government agencies, non-government organizations, agricultural organizations and many landowners. The program has included private lands since the 1990s. However, there is an increased effort to engage more private landowners so as to place traps on more lands in the state. The outreach includes landowner workshops and presentations to various groups, as well as information provided at fairs and similar events. MDC relies largely on landowners contacting the agency when they have feral hog problems and visits to individuals.

The outreach is working; the number of landowners asking for assistance is rising.

The numbers of hogs removed has also risen. During 2016, 5,358  were removed as part of the program. During the first seven months of 2017, From January 1 through July 31, 2017 MDC and its partners removed 4,703 feral hogs.  This is more than a thousand more than had been removed during the same period in 2016.

The program is not cheap; the Conservation Commission approved $1.8 million for fiscal year 2018. These funds cover primarily trapping and killing activities. Costs for MDC staff time and fuel are not included. Most of the MDC staff assisting the program do so as an additional duty. Recently, MDC has hired Mark McLain as the Feral Hog Elimination Team Leader to coordinate MDC feral hog elimination efforts statewide.

Information for this blog came in part from an MDC press release here  and Alan Leary and Mark McLain of the Missouri Department of Conservation. However, the views presented here are those of the Center for Invasive Species Prevention, not the Missouri Department of Conservation.



Mayer, J.J. 2014. Estimation of the Number of Wild Pigs Found in the Unted States. August 2014 SRNL-STI-2014-00292, Revision 0.


U.S. Department of Agriculture Animal and Plant Health Inspection Service Final Environmental Impact Statement. Feral Swine Damage Management: a National Approach May 27, 2015


We welcome comments that supplement or correct factual information, suggest new approaches, or promote thoughtful consideration. We post comments that disagree with us — but not those we judge to be not civil or inflammatory.


Posted by Faith Campbell

Thank Your Senators!!!


Congress is now considering funding for various agencies and programs for Fiscal Year 2018 – which begins on October 1, 2017. Both the House and Senate Appropriations committees have adopted bills to fund APHIS (in the agriculture appropriations bill) and USFS (in the interior appropriations bill). Once these are passed – I expect with little change – by the appropriate chambers, the two very different bills will be reconciled by a Conference Committee made up of members of both the House and Senate and then passed in final form.

Please thank the Senators on the Agriculture Appropriations Subcommittee for their strong support for APHIS’ programs targeting tree pests. Ask them to maintain this support during the Conference – where the House members will be pushing for cuts.

To read the bills and accompanying reports, go here for the House appropriations bill for USDA, (including APHIS); here for the House Interior bill (including the USFS).  Go here for the Senate appropriation bill for USDA.  (Links to the bills and reports are at the end of each press release.) The Senate Appropriations Committee has not yet acted on the Interior bill.


Animal and Plant Health Inspection Service

Appropriators are working under severe pressure given the large spending reductions proposed by the President in the Administration’s budget sent to the Congress earlier in the Spring.

The House appropriated $906 million for APHIS. This is $40 million less than in FY17 but $96.4 million more for APHIS than the Administration requested. The House agriculture appropriations bill made significant cuts in the Tree and Wood Pests program in order to stay within its overall total while maintaining or expanding other programs. The result would devastate the Tree and Wood Pests program. The House bill cuts funding for this program by 30% from the level provided in recent years – from $54 million to $38 million.

The Senate bill, in contrast, increases funding for the Tree and Wood Pests program by $2 million – from $54 million to $56 million. The Senate was able to do this because its bill provided significantly more money for APHIS than did the House: the Senate bill appropriated $953.2 million for APHIS, $7 million above the FY17 funding level; $143.2 million above the Administration’s budget request; and $47 million above the House funding level.

I have blogged often about the necessity of maintaining the Tree and Wood Pest program. In recent years, APHIS’ Asian longhorned beetle (ALB) eradication program has cost $35 – $40 million per year. The program has succeeded in shrinking the New York infestation by 85% and the Massachusetts infestation by 34%. The Ohio infestation has also been reduced – although by considerably less. In its FY2016 annual report, APHIS said the infestation area had been cut by 15%. However, earlier in July APHIS announced that the Ohio infestation is larger than previously known. The quarantine zone was expanded from 61 to 62 square miles. Now is not the time to abandon the 21-year old ALB eradication effort. For a reminder of the threat this insect poses to our hardwood trees, see the write-up here.

The report from the Senate Committee link says that it is “essential” to complete eradication of the ALB.

APHIS and the states have already agreed to cut back the agency’s efforts to regulate movement of ash wood in order to slow the spread of the emerald ash borer (EAB). I am unhappy about this retreat. Still, APHIS planned to continue to survey for EAB in unregulated areas, to educate appropriate publics, to coordinate with affected states, and to produce and disperse biocontrol agents. The Senate funding level – unlike the House funding level – would allow APHIS to maintain these vitally important activities aimed at protecting America’s urban and wildland forests from EAB (For a reminder of that threat, see the write-up here).

Finally, states and stakeholders will expect APHIS to continue its program to slow the spread of the gypsy moth – a program which has received from the Tree and Wood Pest program $5 – $6 million per year in recent years. APHIS must also be prepared to eradicate any newly detected outbreaks, especially of the Asian gypsy moth on the West coast.

I have repeatedly argued that APHIS should expand its program so as to address the many additional tree-killing pests introduced in recent years, including

  • Redbay ambrosia beetle / laurel wilt disease
  • Sirex woodwasp
  • Goldspotted oak borer
  • Walnut twig beetle and thousand cankers disease
  • Soapberry borer
  • Polyphagous & Kuroshio shot hole borers
  • Velvet longhorned beetle
  • Spotted lanternfly

Therefore, I rejoice to see that the Senate report link says: “The Secretary is directed to report to the Committee regarding the steps being taken to eradicate the Asian long-horned beetle and spotted lanternfly and to minimize the spread of other pests such as the polyphagous and Kuroshio shot hole borers (emphasis added).

The Senate report also calls on APHIS to continue efforts to control the coconut rhinoceros beetle in Hawai`i and Ceratocystis disease  That latter is presumably the pathogen causing rapid `ohi`a death in Hawai`i.

The other APHIS program which has supported programs targetting tree-killing pests is the Specialty Crops program. The House bill increased funding for the Specialty Crops program from $156 million to $160 million for FY18. However, $152.3 million of this total – 95% — is allocated to specified agricultural pests, including fruit flies, diseases of citrus trees, glassy winged sharpshooter and European grape vine moth, pale cyst nematode, and light brown apple moth. This means that little is left for addressing sudden oak death or tree-killing pests next year.

Strangely, APHIS said, in its FY16 Annual Report, that the European grape vine moth had been eradicated. So why does the FY18 House appropriations bill allocate $5 million for this pest? It might be for continued surveillance to verify that eradication has been successful.

The Senate bill provides even more – $166 million – for the Specialty Crops program.  The Senate Committee report instructs APHIS to spend “no less than the fiscal year 2017 level of funding” to manage potential movement of sudden oak death in the nursery trade – without specifying the amount.

The House committee did expand overall funding for plant pests to a total of $294 million. The House report says that this total includes an increase of $12.5 million for a Plant Pest and Disease Management and Disaster Prevention Program. This funding explicitly can be spent on tree and wood pest surveillance as well as the clean plant network and citrus health. This increase is welcome, but it does not make up for the 30% cut in specific funding for the tree and wood pest program. The increased surveillance is of doubtful value if it does not result in eradication or containment efforts!

Again, the Senate bill is more generous; it provides $320,308,000 for plant health.

The decisions made by the House Appropriations Committee clearly show the importance of lobbying by traditional agricultural interests in defending funding for programs of interest to them. Several programs targetting diseases of livestock and poultry were maintained at the FY17 funding level. As noted above, the “specialty crop pests” account was increased.


Those of us who care about protecting our trees must become more visible advocates for these programs.


As in the past, both the House and Senate reports support APHIS’ access to emergency funding to be obtained as transfers from the Commodity Credit Corporation for the “arrest” and eradication of animal and plant pests and diseases that threaten American agriculture. The House language appears to be less restrictive.

Unfortunately, it has been years since APHIS sought – much less received – funding through the emergency provision to address tree-killing pests. This is why CISP and others are proposing to amend the Farm Bill to broaden APHIS’ authority to access these funds when appropriated funds are insufficient to counter tree-killing pests. (See my blog from early July for information about these proposed amendments and how you can support them.)

The House also follows the Administration in calling for greater cost-sharing with States and other cooperators. The Houe report states: “The Committee directs APHIS to maximize the use of cost-sharing agreements or matching requirements with states, territories, producers, foreign governments, non-governmental organizations, and any other recipient of services in order to reduce the cost burden on the agency.”

The President’s budget request called for even more severe cuts and justified these cuts by saying that the programs could be maintained if the states, localities, and industries benefitting from eradication or containment of the ALB and EAB helped pay for the containment program. The budget called for beneficiaries to pay 50% of program costs. However, states, localities, and industries are very unlikely to make up such severe cuts in funding. Already, local governments across the country are spending more than $3 billion each year to remove trees on city property killed by non-native pests. Homeowners are spending $1 billion to remove and replace trees on their properties and are absorbing an additional $1.5 billion in reduced property values and reducing the quality of their neighborhoods (Aukema et al. 2011; full reference at end of blog.)

Remember: thank your senators for their generosity to APHIS’ tree pest programs – especially if they are members of the Senate Agriculture Appropriations subcommittee (members listed below).

John Hoeven, North Dakota

Thad Cochran, Mississippi

Mitch McConnell, Kentucky

Susan Collins, Maine

Roy Blunt, Missouri

Jerry Moran, Kansas,

Marco Rubio, Florida

Jeff Merkley, Oregon

Diane Feinstein, California

Jon Tester, Montana

Tom Udall, New Mexico

Patrick Leahy, Vermont

Tammy Baldwin, Illinois




US Forest Service

The House Interior Committee provided $92,084,000 for Forest Health Management, $2,416,000 below the FY17 funding level but $1,694,000 above the budget request. The Report does not specify the amounts for federal v. non-federal lands, but the Administration’s request specified $54 million for federal lands and $36 million for cooperative programs managing forests on non-federal lands. (As recently as FY2014, the forest health program received more than $100 million per year.)

The House Interior Committee recommends $278,368,000 for Forest and Rangeland Research, $10,146,000 below the FY 2017 funding level and $19,368,000 above the budget request. $75 million  of this total is allocated to the Forest Inventory and Analysis program. The Report says that the Committee does not accept the proposed reduction for invasive species research. This is gratifying. However, I have been unable to find the proposed reduction, and there has never been a “line” specifically for invasive species research. Therefore, I am unclear about what level of funding has been retained. (In past years, the total allocated to research on non-native tree-killing pests averaged about $5 million.)

The Senate Appropriations Committee has not yet acted on the Interior Appropriations bill so I cannot tell you how much money that body will provide for these programs.




Aukema, J.E., B. Leung, K. Kovacs, C. Chivers, K. O. Britton, J. Englin, S.J. Frankel, R. G. Haight, T. P. Holmes, A. Liebhold, D.G. McCullough, B. Von Holle.. 2011. Economic Impacts of Non-Native Forest Insects in the Continental United States PLoS One September 2011 (Volume 6 Issue 9)



We welcome comments that supplement or correct factual information, suggest new approaches, or promote thoughtful consideration. We post comments that disagree with us — but not those we judge to be not civil or inflammatory.

Posted by Faith Campbell


Support Adequate Funding for APHIS Tree-Pest Programs


Congress is now considering funding for various agencies and programs for Fiscal Year 2018 – which begins on October 1. Please contact your Representative and Senators and urge them to support adequate funding for key programs managed by the USDA Animal and Plant Health Inspection Service (APHIS). These are essential for keeping the nation’s forests healthy by preventing introduction and spread of invasive pests. While I would much prefer to increase funding for these programs, that is impossible at this time. So I suggest that you support maintaining last year’s  funding levels for two  budget“lines” under the USDA APHIS Plant Health program: $54 million for the “Tree and Wood Pests” line and $156 million for the “Specialty Crops” line.


I have blogged often about the impacts of non-native insects and pathogens inthe United States — which are enormous. (See Lovett et al. 2016 for a summery.)  As new pests are introduced and established pests spread, these costs will only continue to rise.


Moreover, since 1975, U.S. imports (excluding petroleum products) have risen almost six times faster than APHIS and Customs and Border Protection’s staff capability to inspect  them. As a result of this and other prevention failures, such as insufficiently protective regulations, more than a dozen new plant pests are detected in the United States each year. Since the beginning of the 21st Century, at least 20 woodboring beetles have been detected here, including:

  • Redbay ambrosia beetle / laurel wilt disease;
  • Sirex woodwasp;
  • Goldspotted oak borer;
  • Walnut twig beetle and thousand cankers disease ;
  • Soapberry borer;
  • Polyphagous & Kuroshio shot hole borers; and
  • Velvet longhorned beetle.


Another dozen tree-killing pests that are not wood borers have also been detected, including Spotted lanternfly.



APHIS Programs Target only a Few of the Damaging Pests in the Country


At least in part because of inadequate funding, APHIS currently funds comprehensive programs targeting only four of the  dozens of already- or potentially-serious tree-killing pests already in the country: gyspy moth (both European and Asian); Asian longhorned beetle; emerald ash borer; and sudden oak death.


APHIS also provides limited assistance to programs on  other pests through grants  under the Section 10007 of the 2014 Farm Bill. One example is research to determine host ranges and possible control method for the polyphagous and Kuroshio shot hole borers. However, these funds have not been sufficient to support comprehensive suppression or eradication programs despite the threat posed by these two shot-hole borers. They threaten to kill 26 million trees – more than a third of the trees growing in urban areas in California’s Inland Empire, Coastal Southern California, and Southwest Desert. Absent an active APHIS program to develop effective control measures, the municipalities and homeowners of these regions will be forced to absorb an estimated $36.2 billion (the costs of removing and replacing dead and dying trees) if they want to maintain valuable urban forest canopy.

willow killed by Kuroshio shot hole borer

in Tijuana River estuary, California

photo by John Boland

The shot-hole borers might also threaten trees across the American South. Box elder, sweetgum, and tree of heaven are reproductive hosts for the polyphagous shot hole borer; all are widespread in southern forests. California species of sycamore, oak, and willow are also reproductive hosts; other trees in these genera, which grow widely across the U.S., might also be vulnerable to the shot hole borers.


APHIS also has devoted Section 10007 funds to the spotted lanternfly, which is found in southeastern Pennsylvania. This insect feeds on several crop trees as well as oak, walnut, poplar, and pine trees. Pennsylvania authorities cannot complete eradication of this pest without additional federal funding – which so far is uncertain.


APHIS has helped with trace-forwards to find furniture infested by the velvet longhorned beetle, but has not adopted a program targetting this species in the several states where it appears to be established.


As these examples illustrate, even maintaining current funding levels means that several damaging non-native insects and pathogens continue to spread without a meaningful federal response. Any cuts would only exacerbate the failure of APHIS’ program to protect our forests from non-native insects and pathogens.


Remember, too, that additional introductions are likely in coming years. According to one study, perhaps 35 shipping containers entering the country each day carry damaging pests.

Unloading largest container ship to visit a U.S. East Coast port – “Cosco Development”; Savannah, GA  May 12, 2017; F.T. Campbell

At the same time, we cannot afford for APHIS to reduce its ongoing programs in order to address the other invaders. The  Asian longhorned beetle eradication program, at a cost of $35 – $40 million per year, has succeeded in eradicating 85% of the infestation in New York. (APHIS has just announced that a section of the borough of Queens is free of ALB.) However, the infestations in Massachusetts and Ohio still threaten to spread further into the forests. The $5 – $6 million per year allocated to the gypsy moth appears to be adequate, but APHIS must be prepared to eradicate any newly detected outbreaks, especially of the Asian gypsy moth on the west coast.


APHIS’ emerald ash borer program has received $7 million per year. To reduce future costs, the agency has cut back its regulatory program, so that it enforces regulations only at the infestation’s leading edge. In affected states, APHIS will continue surveys in unregulated areas, outreach, and coordination. These changes, taken together, undermine efforts to prevent the beetle’s spread to the vulnerable rural and urban forests in North Dakota, Oregon, and other states. APHIS is emphasizing production and dispersal of biocontrol agentsrather than regulatory measures

The sudden oak death program – targeting the pathogen Phytophthora ramorum — is under the “Specialty Crops” funding line. This must also be maintained at current levels because SOD threatens such important eastern forest tree species as northern red, chestnut, white, and pin oaks; sugar maple; and black walnut. APHIS regulates movement of nursery stock which could transport this pathogen from the West coast to vulnerable areas in the East. It was learned recently that APHIS needs to add the genus Magnolia to the “filthy five” group which is subject to the most careful regulation.

Whom to Contact

Please ask your Senators and Representative to support maintaining – or even increasing – funding for these APHIS programs. Your contact is especially important if you are represented by one of the members of the House or Senate Appropriations Committee’s Subcommittees on



* Robert Aderholt, Alabama, Chairman

* Kevin Yoder, Kansas

* Tom Rooney, Florida

* David Valadao, California

* Andy Harris, Maryland

* David Young, Iowa

* Steven Palazzo, Mississippi

* Sanford Bishop, Georgia, Ranking Member

* Rosa DeLauro, Connecticut

* Chellie Pingree, Maine

* Mark Pocan, Wisconsin



John Hoeven, North Dakota

Thad Cochran, Mississippi

Mitch McConnell, Kentucky

Susan Collins, Maine

Roy Blunt, Missouri

Jerry Moran, Kansas,

Marco Rubio, Florida

Jeff Merkley, Oregon

Diane Feinstein, California

Jon Tester, Montana

Tom Udall, New Mexico

Patrick Leahy, Vermont

Tammy Baldwin, Illinois




Lovett, G.M., M. Weiss, A.M. Liebhold, T.P. Holmes, B. Leung, K.F. Lambert, D.A. Orwig , F.T. Campbell, J. Rosenthal, D.G. McCullough, R. Wildova, M.P. Ayres, C.D. Canham, D.R. Foster, S.L. LaDeau, and T. Weldy. 2016. Nonnative forest insects and pathogens in the United States: Impacts and policy options. Ecological Applications, 0(0), 2016, pp. 1–19. DOI 10.1890/15-1176.1  available at


Additional recent sources of information on tree-killing pests not being addressed by APHIS:

Article about the damage caused by the goldspotted oak borer:


GSOB at Irvine Regional Park in OC

Goldspotted Oak Borer video

The Los Angeles Times has published two recent articles about the shot hole borers at



We welcome comments that supplement or correct factual information, suggest new approaches, or promote thoughtful consideration. We post comments that disagree with us — but not those we judge to be not civil or inflammatory.


Posted by Faith Campbell


Pest threat to West Coast confirmed – authorities should respond to this information by taking protective measures

 Numbers of non-native pests in counties of the 49 continental states; Map prepared by Andrew Liebhold, USFS in 2014. More recent introductions are not represented; nor are insects native to some part of North America

Currently, the Northeast and Midwest have the highest number of non-native, tree-killing insect and pathogen species (see map above). However, Pacific coast states have two-thirds the numbers of pest species of the Northeast – and are catching up. Two articles modeling the likelihood of new pest introductions point to the particular vulnerability of the Pacific Coast states – especially California – to pest introductions from Asia.


Koch et al. 2011 (see reference at the end of the blog) utilized various sources of information about volumes of imports likely to be associated with wood-boring pests — stone; raw wood and wood products (including crates & pallets); metals; non-metallic minerals; auto parts; etc. From this, the authors estimated both a nationwide establishment rate of wood-boring forest insect species and the likelihood that such insects might establish at more than 3,000 urban areas in the contiguous U.S. While their estimate was based on 2010 imports, they also projected rates for 2020.


See my blog from March 10  for various scientists’ estimates of  the overall, nationwide rate of introduction.  Koch et al. estimated the nation-wide introduction rate at between 0.6 and 1.89 forest insects and pathogen species per year for the period 2001–2010 and 0.36 and 1.7 species per year for 2011–2020.  In other words, we should expect a new alien forest insect species to become established somewhere in the United States every 2–3 years. If one-tenth of these new introductions turn out to cause significant damage, then we can expect a “significant” new forest pest every 5–6 years.


Pacific coast states – especially California – are at highest risk. 

Koch et al. evaluated the introduction risk for 3,126 urban areas across the country. The metropolitan area with the highest risk is Los Angeles–Long Beach–Santa Ana, California. For both 2010 and 2020, the predicted rates for a new pest establishing there is every 4–5 years.


Looking ahead to 2020, the situation worsens for three California metro areas – Los Angeles–Long Beach–Santa Ana; San Diego; and Riverside-San Bernardino. At San Francisco-Oakland, the predicted establishment rates remain steady. Most of the rest of the top 25 urban areas show decreases in establishment rate between 2010 and 2020.


This rising risk to California urban areas is driven by the growth of imports from Asia. For the four California urban areas, the establishment rate of Asian species is projected to increase 6–8% between 2010 and 2020. The Los Angeles–Long Beach–Santa Ana area could potentially expect the establishment of an alien forest insect species originating specifically from Asia alone (not the entire world) every 4–5 years.

[The polyphagous and Kuroshio shot hole borers are examples of recently introduced pests from Asia.  Both are described, inter alia, here; a distribution map for PSHB is available here.]

Koch et al. note that the Los Angeles metropolitan area has a dense human population with corresponding high demand for goods and materials, so a substantial proportion of imports clearing the port remains in the areas.  Furthermore, widespread planting of non-native plants provides a range of potential hosts that can support invaders that would not otherwise become successfully established.


A second source also indicates a heightened risk to Pacific Coast states. Yemshanof et al. used similar modeling techniques to evaluate the risk of tree pest introductions to Canada … and to the U.S. in the form of transshipped goods.  (See my earlier blog.)


The Yemshanof et al. model showed that 8% of all forest pests introduced to the U.S. on imported wood or wood packaging — as estimated by Koch et al. — would come through goods transshipped through Canada. The risk is highest to the Pacific Coast states since they are the most likely to receive Asian goods transiting through Canada.


Note that the phytosanitary agencies in both the U.S. and Canada proposed in 2010 that wood packaging originating in one of the countries and shipped to the other be required to meet the international regulations under ISPM#15. However, APHIS was unable to adopt this regulation under the Obama Administration, and such an action seems even less likely under the Trump Administration. Canada is unlikely to adopt the new rules without a coordinated U.S. action.


Southern California also imports lots of plants – another pathway for pest introductions.


Koch et al. suggest that authorities use these models to prioritize border control efforts (e.g., commodity inspections), post-border surveillance, and rapid-response measures.  I see some problems with these suggestions.  First, enhanced commodity inspections are not likely to measurably diminish the risk of introduction to the region. Second, rapid-response measures require both increased funds – which are expected to decrease; and political will. I have blogged several times about California’s decisions to not implement official, regulatory responses to recently detected pests.


Instead, people in the region should actively build alliances and press their regional political leaders – governors, mayors, senators, members of Congress – to demand that the U.S. Department of Agriculture and the Congress adopt policies that will strengthen protection for the region’s trees.


New pest detected in California!


California authorities have detected a new woodboring beetle – the olive wood borer (Phloeotribus scarabaeoides). It was detected in an olive tree in a grape vineyard in Riverside County. This is the first detection of the species in the Western Hemisphere. Known or suspected hosts include several trees in the olive family (Oleaceae), including olive trees, privet, ash, and common lilac; as well as oleander (Apocynaceae).


Since this new pest is native to the Mediterranean region, it does not appear to be an example of the risk to California from Asia …  The source (Diagnostic Network News; see below) does not speculate on the pathway by which the introduction occurred.



What Can We Do?


Ask your state’s Governor to

  • Communicate to the USDA Secretary the need to amend policies & regulations

(Coordinate this effort with governors of other states.)

  • Put forest pest issue on the agenda of National Governors’ Association
  • Ask your state’s Congressional delegation to pressure USDA Secretary to amend policies and regulations
  • Communicate concern about these pests to the media — and propose solutions.


Ask your state’s agricultural and forestry agency heads to

  • Ask their national associations to support proposals to USDA Secretary & Congress. These associations include
    • National Association of State Departments of Agriculture (NASDA)
    • National Association of State Foresters (NASF) or its Western regional group, the Council of Western State Foresters
  • Communicate to the media both the agency’s concern about tree pest threats and proposed solutions.


We can also act directly.

  • Ask mayors and officials of affected towns and counties to
  • Push proposals at regional or National Conference of Mayors or National Association of Counties
  • Instruct local forestry staff to seek support of local citizen tree care associations, regional and national associations of arborists, Arbor Day & “Tree City” organizations, Sustainable Urban Forest Coalition, etc.
  • Reach out to local media with a message that includes descriptions of policy actions intended to protect trees — not just damage caused by the pests
  • Ask stakeholder organizations of which you are a member to speak up on the issue and support proposed solutions; e.g.,
    • Professional/scientific associations
    • Wood products industry
    • Forest landowners
    • Environmental NGOs
    • Urban tree advocacy & support organizations


  • Encourage like-minded colleagues in other states to press the agenda with their state & federal political players, agencies, & media.
  • Communicate to the media both your concern about tree pest threats and proposed solutions.


What Specific Actions Should We Suggest be Taken?

I suggest a coordinated package.  However, you might feel more comfortable selecting a few to address each time you communicate with a policymaker. Choose those on which you have the most expertise; or that you think will have the greatest impact.

  • Make specific proposals, not vague ideas (see below for suggestions)
  • Always include information about how the pests arrive/spread (pathways such as imports of crates & pallets, or woody plants for ornamental horticulture) and what we can do to clean up those pathways  (Don’t just describe the “freak of the week”)
  • Always point out that the burden of pest-related losses and costs falls on ordinary people and their communities. (Aukema et al. 2011 provides backup for this at the national level; try to get information about your state or city.)
  • We need to restore a sense of crisis to prompt action – but not leave people feeling helpless! We need also to bolster understanding that we have been and can again be successful in combatting tree pests.


Specific actions that will reduce risk that pests pose to our trees:

  • Importers switch from packaging made from solid wood (e.g., boards and 4”x4”s) to packaging made from other materials, e.g., particle boards, plastic, metal …
  • Persuade APHIS to initiate a rulemaking to require importers to make the shift. This can be done – although international trade agreements require preparation of a risk assessment that justifies the action because it addresses an identified risk (see my earlier blogs about wood packaging).
  • Create voluntary certification programs and persuade major importers to join them. One option is to incorporate non-wood packaging into the Department of Homeland Security Bureau of Customs and Border Protection’s (CBP) existing Customs-Trade Partnership Against terrorism (C-TPAT) program.


  • Tighten enforcement by penalizing shipments in packaging that does not comply with the current regulations
  • Persuade CBP and/or USDA to end current policy under which no financial penalty is imposed until a specific importer has been caught five times in a single year with non-compliant wood packaging. APHIS has plenty of authority to penalize violators under the Plant Protection Act [U.S.C. §7734 (b) (1)].
  • Restrict imports of woody plants that are more likely to transport pests that threaten our trees
  • In 2011, APHIS adopted regulations giving it the power to temporarily prohibit importation of designated high-risk plants until the agency has carried out a risk assessment and implemented stronger phytosanitary measures to address those risks. Plants deserving such additional scrutiny can be declared “not authorized for importation pending pest risk assessment,” or “NAPPRA”. A list of plants posing a heightened risk was proposed nearly 4 years ago, but it has not been finalized – so imports continue. APHIS should revive the NAPPRA process and utilize prompt listing of plants under this authority to minimize the risk that new pests will be introduced.
  • APHIS should finalize amendments to the “Q-37” regulation (proposed nearly 4 years ago) that would establish APHIS’ authority to require foreign suppliers to implement integrated programs to minimize pest risk. Once this regulation is finalized, APHIS could begin negotiating agreements with individual countries to adopt systems intended to ensure pest-free status of those plant types, species, and origins currently considered to pose a medium to high risk.


  • Strengthen early detection/rapid response programs by
  • Providing adequate funds to federal & state detection and rapid response programs. The funds must be available for the length of the eradication program – often a decade or more.
  • Better coordinate APHIS, USFS, state, & tribal surveillance programs.
  • Engage tree professionals & citizen scientists more effectively in surveillance programs.





Koch, F.H., D. Yemshanov, M. Colunga-Garcia, R.D. Magarey, W.D. Smith. Potential establishment of alien-invasive forest insect species in the United States: where and how many? Biol Invasions (2011) 13:969–985


Western Plant Diagnostic Network First Detector News. Winter 2017. Volume 10, Number 1.


Yemshanov, D., F.H. Koch, M. Ducey, K. Koehler. 2012.  Trade-associated pathways of alien forest insect entries in Canada. Biol Invasions (2012) 14:797–812


We welcome comments that supplement or correct factual information, suggest new approaches, or promote thoughtful consideration. We post comments that disagree with us — but not those we judge to be not civil or inflammatory.

Posted by Faith Campbell

Statement of the Center for Invasive Species Prevention on withdrawing its proposal to the U.S. Fish and Wildlife Service to add the red swamp crayfish to the Lacey Act for further analysis


On September 26, 2016, the Center for Invasive Species Prevention (CISP) petitioned the U.S. Fish and Wildlife Service (USFWS) to add 43 species to those regulated under the Lacey Act. Among these species was the red swamp crayfish (Procambarus clarkia). We now plan to withdraw and reconsider that species after we do more analysis.

We recognize that this crayfish species has major economic value. It is an important part of peoples’ livelihoods in Louisiana in particular. By no means do we want anyone in that business to feel threatened by the Petition.

Right now, the CISP Petition has no official status within the Federal government. It has not been published in the Federal Register nor has the USFWS indicated any intent to make it an official agency proposal. Even if it did, such a listing would not affect collecting, harvesting, rearing or selling crawfish directly within Louisiana or within other range States.

We would like to clear up some other confusion. It is true that the Lacey Act is used to prevent first-time imports of non-native “injurious wildlife” into the United States. The law has other provisions, though, that help prevent additional introductions of damaging species already in the country, that help stop harmful species’ interstate spread, and that apply to native species invading outside of their native ranges. These latter aspects can provide nationwide protection at a time when individual State’s laws are uneven. Populations of the red swamp crayfish are turning up in the wild. One can see how quickly it has become a nationwide problem in the wild on the animated map at the U.S. Geological Survey’s website. Approximately a dozen states have responded with their own prohibitions or other regulations.

We do think it is important to set a precedent that USFWS acts, in some way, on all species it determines to be of highest risk of invasiveness. Our Petition aimed to get this ball rolling. Much further analysis and public comment would go into any eventual decisions that USFWS makes on individual species. It could leave regulation of species in widespread trade to individual States.  On the red swamp crayfish, CISP will withdraw that species from our Petition and reconsider what the best options are. Then we will consider whether a new Petition tailored to that species is warranted.


posted by Peter Jenkins

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 uncivil or inflammatory.

Support Effort to Declare UN “International Year of Plant Health”


Officials who carry out plant health programs around the world are trying to build public understanding and support for such programs by organizing an “International Year of Plant Health”. Such “international years” are designated by the United Nations General Assembly – so – as you can imagine – years of planning go into the effort.

So far, the proposal has been approved by the Council of Agricultural Ministers and will be considered by the Conference of the UN Food and Agriculture Organization in June 2017. If approved by the FAO, the proposal will then be put to the full United Nations by sponsoring nations’ diplomats.  The General Assembly meeting in 2018 would consider the proposal – assuming FAO does forward it.

The goal of the proposed Year is to persuade decision-makers and the public that protecting plants by preventing and containing pests is an essential foundation for countries’ efforts to achieve food security, economic development, and environmental protection. Organizers also want people to know that plant protection is also a necessary component of policies to facilitate trade.

The events associated with the “International Year of Plant Health” will recognize plant health disciplines and the many people and organizations who contribute at the global, regional and national levels. It is not intended to celebrate specifically the International Plant Protection Convention, or the standards and other measures it has adopted.

Plant health professionals are concerned that funds and other resources dedicated to plant protection services are shrinking despite the growing threat to agricultural and natural resources from the spread of pests. Without more attention, they fear that resources will fall even farther behind the need as agencies confront demands from other global challenges. They intend to make the case that healthy plants help solve — rather than compete with – such other big problems as climate change, changing migration patterns, biosecurity concerns, and economic development.

The proponents specific objectives are to:

  1. Raise awareness among political decision makers at global, regional, and national levels.
  2. Build up plant health efforts and resources at all levels to better match growing needs linked to increasing trade and the new pest risks caused by climate change.
  3. Educate the broader public so it better understands the importance of protecting plant health.
  4. Enhance dialogue and stakeholder involvement in plant health.
  5. Increase information about the state of plant protection in the world.
  6. Promote partnerships on national, regional, and global levels.

It is hoped that success in raising awareness and understanding will result in sustainable funding of national plant health systems that will, in turn, enable

  • Improved capacity to take on more plant health related projects and programs
  • More effective collaboration and solutions at the global level
  • Better plant health situation in all countries.

I assume that readers of this blog are stakeholders in the global plant protection network. Most of you are professionally engaged in forest or nature conservation (perhaps through research), or are active conservation advocates. Some of you might be affiliated with trade and grower associations. Please consider how you can help educate political decision makers about the importance of protecting plants from non-native organisms that potentially threaten native ecosystems or agricultural and horticultural production. The first task is to ensure that the incoming Secretary of Agriculture actively supports the proposal both among his colleagues (e.g., with the Department of State) and at the FAO Conference in June. Please use your contacts in the government – including the Congress – and with other stakeholders to promote the idea.

Assuming that the International Year of Plant Health is approved, there will be many opportunities to lead or collaborate in the planned outreach efforts. Our engagement might help shape the message. For example, we need to ensure attention to the many challenges currently hindering plant health protection,  as discussed in my blogs and in numerous peer-reviewed articles and reports. Also, we need to make certain that the environmental and biodiversity aspects of plant protection are prominent among considerations.

And if the Year is not approved?  In my mind, that action would prove even more that we need to educate those who do not yet see why healthy trees and other plants matter!

Let me know what you think we might do – by sending me an email using the “contact us” button. Together, we can use this proposal to join coalitions with the goal of promoting stronger, more effective protection for our forests and other natural resources!


Posed 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 uncivil or inflammatory.

Help promote new film about tree-killing pests!

A new film demonstrating the impact of non-native tree-killing insects and diseases will be shown on or around Arbor Day (April 20). You can help ensure that lots of people see the film!!! Contact the program manager at your local PBS channel to ask that the channel broadcast the film.

ash tree killed by EAB; Ann Arbor, MI; courtesy of Major Hefje
ash tree killed by EAB; Ann Arbor, MI; courtesy of Major Hefje

“Trees in Trouble: Saving America’s Urban Forests” focuses on emerald ash borer in Cincinnati. The film explores our connections to the trees and forests in our communities – and the threats to those trees. The film’s website links viewers to resources for taking action.

To see clips from the film and other resources go to this site.

The film was produced by Torrice Media. Featured experts and speakers include Prof. Dan Herms of Ohio State, Jenny Gulcik, a community forestry consultant, and Cincinnati Council member Wendell Young.
As we all know, killer pests threaten trees across the country, not just in southern Ohio! Such pests are usually introduced first in cities – not necessarily ports! – because that is where crates and pallets, imported ornamental plants, and other articles to which pests attach arrive. Furthermore, trees along streets and in yards and parks are often more vulnerable than forest trees to such introduced pests because they are often subject to other stresses such as soil compaction, air pollution, elevated temperatures, and salt exposure. Finally, city trees are often planted as multiple individuals of the same species; when a pest that attacks that species arrives, entire neighborhoods can lose their tree canopy – and the real values that canopy provides.
Because of the high value of urban trees, these pests’ greatest economic damage is in urban and suburban areas. The study by Julianne Aukema and others documented that municipalities spend more than $2 billion annually to remove trees killed by non-native pests. Homeowners spend $1 billion a year removing trees killed by non-native pests, and another $1.5 billion is lost in property values due to tree mortality.

Thus, it is vitally important that American city dwellers learn about the values that trees provide to them, the threat to those values from introduced pests, and what they can do to minimize this threat. “Trees in Trouble” is a tool to advance citizens’ understanding of these issues through a combination of broadcasts, compelling video presentations and active civic engagement efforts linked to the film.

goldspotted oak borer
goldspotted oak borer

Some people – less familiar with the issue than we are – do not immediately understand the relevance of Cincinnati’s story to other cities. We know that while the trees and killers differ across the country, the cost to the communities is the same: destruction of trees that provide shade and other important ecosystem services and create our sense of home. Plus, the ways these pests are introduced are the same – and so are the steps we can take to reduce this threat.

[The goldspotted oak borer illustrates the universality of this threat – trees in southern California are being killed, too!]
You can help overcome this roadblock!
If you would like to help promote the film to your local PBS station or to local viewers, contact Andrea Torrice at 513-751-7050 or here

If you would like to obtain a copy of the film to screen to your group, contact Andrea Torrice at the same phone number or website. (Andrea is Italian; her name is pronounced “to re chay”, with the accent on “re”.)
Aukema, J. E., B. Leung, K. Kovacs, C. Chivers, K. O. Britton, J. Englin, S. J. Frankel, R. G. Haight, T. P. Holmes, A. M. Liebhold, D. G. McCullough, and B. Von Holle. 2011. Economic Impacts of Non-Native Forest Insects in the Continental United States. Plos One 6.

Posted by Faith Campbell

Funding Shortfalls Threaten Our Trees – & Are Becoming Worse

Experts have recognized for two decades that funding of federal programs intended to prevent or respond to introductions of invasive species is inadequate.  As regards tree-killing insects and pathogens, there have been spikes in the past, spurred by, first, detection of Asian longhorned beetle  and emerald ash borer, then by federal spending increases to support recovery from the Great Recession.

But with renewed pressure to reduce the federal budget, programs operated by APHIS and the USDA Forest Service have suffered significant cuts in spending. For a history of these cuts, read Chapter 3 in Fading Forests III .

Funding for key programs continue. Most alarming is that these cuts are suggested by the Administration! in its annual budget sent to Congress. I don’t know whether the cuts are suggested by the agencies, or instead are imposed by higher-ups in the Department of Agriculture or at the President’s Office of Management and Budget.

White House

Certainly there is competition for the available funds. APHIS is funded by the Agriculture Appropriations bill, which also funds agriculture programs that enjoy strong lobbying support as well as food stamps. The Forest Service is being squeezed by the ever-higher costs of managing wildfires.

Still, these cuts threaten to expose our wildland, rural, and urban forests to permanent destruction by non-native, tree-killing insects and pathogens.

Congress determines the final funding levels through the appropriations process.

Capitol  Members of Congress work for us!!

Ask your member of Congress & senators to support adequate funding for APHIS & USFS programs that counter invasive, non-native tree-killing pests.

Congress’ actions are at the following stage as of the third week in July:


The House Subcommittee on Agricultural Appropriations bill had cut funding for “tree and wood pest” group – although the bill did increase funding for the “specialty crops” program.

In both cases, groups with which I work had asked to maintain the FY15 level.

The Senate bill, adopted by the full Appropriations Committee on 16 July, has restored funding to the “tree and wood pest” line! Possibly because of this increase, it holds the “specialty crops” program funding to the FY15 level.

Funding specifics:

HOUSE Agriculture appropriations bill maintains overall funding for APHIS at the FY15 level ($871 million). This is $15 million above the President’s request in his budget; and about the same as the level of funding for the current fiscal year (FY 2015). Within this amount, the following is allocated to programs that address tree-killing pests:

  • $158,000,000, to remain available until expended, for specialty crop pests

(a very small proportion of this account, about $5 million, goes to sudden oak death management)

  • $45,500,000, to remain available until expended, for tree and wood pests (e.g., ALB, EAB)


SENATE Agriculture appropriations bill raised overall funding for APHIS to $876 M — $20 million above the President’s budget request and $5 M above both the current year and House level. Within this amount, the following is allocated to programs that address for tree-killing pests:

  • $156,000,000, to remain available until expended, for specialty crop pests
  • $54,000,000, to remain available until expended, for tree and wood pests


As I said above, it is disturbing that these programs do not enjoy sufficient support within the Administration. We all need to increase our lobbying of USDA – both at the APHIS level and above; and at OMB.


USDA Forest Service

Both the House and Senate Interior Appropriations subcommittee bills cut USFS funding for both research and forest health management.

The House interior appropriations bill provides only $207 million for research other than Forest Inventory and Assessment. The Senate interior appropriations bill provides $211 million for research other than FIA. Both figures are below the $220 million allocated for the current year (FY2015) and higher levels in previous years.

The House bill provides only $99 million for forest health management (on both federal and non-federal or “coop” lands). The Senate bill provides $100.7 million. Again, both figures are below the $104.6 million provided in FY15 and higher levels in previous years.

Funding for all USFS programs is under extreme pressure by the growing cost of fighting wildfires. Until this problem is resolved, it will be extremely difficult to obtain additional funds for other programs – even in the face of rising numbers of tree-killing pests across the country. There are also questions within OMB and among some advocacy groups about whether the USFS should assist states and cities in containing tree-killing pests. Some argue that the USFS should confine its efforts to pests that are attacking trees in National forests. My reply: if you wait for ALB or other pests to reach National forests before responding, you have thrown away any chance of containing the outbreak.