Contents

1. Introduction
2. Vertebrates: Mammals, Reptiles & Fish
3. Insects & Arthropods
4. Invasive Plants
5. Pathogens & Diseases
6. Impacts on Seed Production and Seed Quality
7. Economic & Ecological Consequences of Key Species
8. Management & Control Efforts
9. Conclusion

1. Introduction

Invasive species represent one of the most serious threats to biodiversity, ecosystem function, and even economic stability in the United States. These organisms—animals, plants, pathogens—that are non-native to a given ecosystem can outcompete, prey on, or otherwise displace native species, altering food webs, degrading habitat, and imposing large costs on human communities. The term “high‑impact” refers to those invasive species that inflict particularly severe ecological or economic damage, whether through habitat destruction, loss of native species, disruption of ecosystem services, disease spread, or large-scale cost to property owners and public agencies.

This list of 50 species spans vertebrates (mammals, fish, reptiles), insects and arthropods, plants, and pathogens. Some affect entire landscapes; others are more localized but nonetheless critical. While not all directly impact seed production, the most disruptive species often destabilize ecosystems in ways that indirectly reduce the viability, abundance, or diversity of native plants and their seeds. In this discussion, we highlight these key invaders, describe their impacts, and examine which species pose a direct threat to seed quality or production.

2. Vertebrates: Mammals, Reptiles & Fish

Nutria (Myocastor coypus)
Nutria are large, semi-aquatic rodents originally introduced from South America for fur farming. Established in many U.S. states, they cause serious damage in wetlands by eating both above-ground vegetation and underground rhizomes, tubers, and roots. Their voracious feeding uproots plants, destabilizes soil, and leads to erosion and marsh loss. Over time, areas once dense with marsh vegetation can convert into open water, reducing habitat for waterfowl, fish, and other marsh-dependent species. They also burrow into banks and levees, weakening flood-control structures, irrigation canals, and shorelines. Nutria carry parasites and pathogens—such as nematodes, liver flukes, and tapeworms—that may contaminate water, posing risks to livestock and human health.

Wild Boar / Eurasian Wild Pig (Sus scrofa)
Wild boar, also known as feral pigs, are highly destructive invaders due to their rooting behavior. They forage by digging up large areas of soil, disturbing native vegetation, and competing with native wildlife. Their omnivorous diet lets them prey on small animals while also consuming plant matter, which leads to degraded habitats, reduced biodiversity, and damaged agricultural fields. Because of their high reproduction rate and adaptability, they can quickly establish dense populations, making removal difficult. In addition, they can spread diseases such as swine brucellosis and pseudorabies, posing a risk to livestock and wildlife.

American Bullfrog (Lithobates catesbeianus)
Originally native to parts of the United States, the American bullfrog has been introduced to many areas where it becomes invasive. This amphibian is a voracious predator across life stages, eating invertebrates, smaller amphibians, reptiles, birds, and even small mammals. It also competes with native amphibians for breeding habitats and food. Bullfrogs can host pathogens like chytrid fungus and ranaviruses, which threaten other amphibian populations. Their presence can severely disrupt local aquatic communities, reducing the abundance of native frogs and other species.

Burmese Python (Python bivittatus)
In regions like southern Florida, Burmese pythons have become top predators in invaded habitats. These large constrictor snakes consume mammals, birds, and reptiles, often wiping out populations of small to medium-sized native species. Their predation can ripple through food webs by reducing prey populations and altering predator-prey dynamics. Because of their size and cryptic behavior, pythons are challenging to control, and their long lifespans and reproductive capacity make eradication extremely difficult.

Lionfish (Pterois spp.)
Lionfish are one of the most notorious marine invasive species in U.S. coastal waters, especially in the Atlantic and the Caribbean. These venomous fish have no natural predators in their invaded range, which allows their populations to explode. Lionfish feed on a wide variety of reef fish and invertebrates, reducing native biodiversity and altering reef community structure. Their predation on juvenile fish can impair reef resilience and recovery, and they are particularly harmful to commercial and reef‑dependent species. Their spread disrupts ecological balance and threatens the health of coral reefs.

Northern Snakehead (Channa argus)
Introduced into U.S. freshwater systems, particularly in the Mid-Atlantic and Southeast, northern snakeheads are aggressive predatory fish. They can breathe air, survive in low-oxygen water, and even move short distances over land, giving them a competitive edge. They prey on native fish, amphibians, and invertebrates, often to the detriment of local species. Their rapid reproduction and adaptability to various freshwater habitats make them a serious threat to native aquatic biodiversity and local fisheries.

Round Goby (Neogobius melanostomus)
Originally from the Black and Caspian seas, round gobies have established in the Great Lakes and other freshwater systems. They are small but ecologically disruptive: they outcompete native species for habitat and food, feed on the eggs of native fish, and alter benthic (bottom) community dynamics. Their prolific reproduction and ability to tolerate a range of environmental conditions make them a persistent challenge for native fish conservation.

New Zealand Mudsnail (Potamopyrgus antipodarum)
Though not vertebrate, the New Zealand mudsnail deserves mention among high-impact aquatic invaders. This tiny freshwater invertebrate reproduces parthenogenetically, enabling rapid population growth from a single individual. It competes heavily with native macroinvertebrates for food and space, especially in streams and rivers. Their dense populations can dominate streambeds, altering nutrient cycling and food webs, which undermines the stability of native aquatic ecosystems.

3. Insects & Arthropods

Emerald Ash Borer (Agrilus planipennis)
One of the most destructive invasive forest pests in North America, the emerald ash borer targets ash trees, killing them by feeding on the inner bark. Since its detection, it has decimated millions of ash trees in urban, suburban, and forested landscapes. The cost of tree removal, treatment, and replacement runs into the billions. Local governments, property owners, and utilities bear heavy financial burdens. The loss of ash trees also diminishes urban canopy cover, reducing ecosystem services such as shade and air cleansing.

Asian Long‑Horned Beetle (Anoplophora glabripennis)
This wood-boring beetle attacks a wide variety of hardwood trees, including maples, birches, and elms. Larvae tunnel through the wood, weakening structural integrity and eventually killing the tree. Infested trees must often be removed to prevent the spread, which is expensive and labor-intensive. Because it affects both forest and urban trees, the beetle’s impact is broad, threatening natural ecosystems, residential landscapes, and street trees.

Spotted Lanternfly (Lycorma delicatula)
The spotted lanternfly is a sap-feeding insect that attacks a variety of plants, particularly fruit trees, ornamentals, and vines. Its feeding weakens plants, reduces fruit yield, and can cause dieback. Because it can move quickly and lay egg masses on many surfaces, it spreads rapidly. It is also a major pest for grape growers, tree nurseries, and orchard operations, and quarantine measures further compound its economic impact.

Asian Citrus Psyllid (Diaphorina citri)
This small insect is a vector for citrus greening disease (Huanglongbing), one of the most devastating diseases affecting citrus. When psyllids feed on plants, they transmit the pathogen, which causes the tree to decline and ultimately die. There is no cure, and infected trees produce malformed fruits or none at all. This psyllid-disease complex threatens citrus production on a large scale, impacting growers, exporters, and regional economies.

Red Imported Fire Ant (Solenopsis invicta)
These aggressive ants pose risks to agriculture, wildlife, and humans. They build mounds that interfere with farming equipment and can damage crops. Their stings harm livestock, wildlife, and people, provoking costly medical and veterinary interventions. Fire ants also compete with native insects and ground-nesting birds, altering local ecological balances.

Hemlock Woolly Adelgid (Adelges tsugae)
This tiny sap-sucking insect attacks hemlock trees, particularly in the eastern U.S. It feeds on the tree’s stored nutrients, eventually killing it. Large-scale infestations have decimated hemlock populations, which alters forest structure and degrades habitats for species that rely on hemlock-dominated ecosystems. Because hemlock provides shade and stabilizes slopes, its loss also has cascading ecological impacts.

Asian Tiger Mosquito (Aedes albopictus)
Originally from Asia, this mosquito species is now widespread in the U.S. It transmits diseases such as dengue, chikungunya, and Zika, posing public health risks. Unlike many native mosquitoes, the Asian tiger mosquito thrives in urban environments, breeding in small water containers. Its adaptability makes it a persistent threat, and controlling it places demands on public health resources.

Brown Marmorated Stink Bug (Halyomorpha halys)
This agricultural pest feeds on a wide variety of crops, including fruits, vegetables, and ornamental plants. Its sucking mouthparts pierce plant tissues, causing deformities, discoloration, and reduced yield. It also invades homes in large numbers seeking shelter in winter, making it a nuisance pest beyond the agricultural impacts.

Giant African Snail (Lissachatina fulica)
This large terrestrial snail eats a broad variety of plant species, including important crops and ornamentals. It can damage infrastructure by burrowing and climbing walls. In addition to its agricultural impact, it is a public health concern because it can host parasites that infect humans.

Formosan Subterranean Termite (Coptotermes formosanus)
This invasive termite species causes both structural and ecological damage. It consumes wood rapidly, infesting buildings, utility poles, and trees. Beyond economic costs in urban areas, it also degrades living trees, weakening them and sometimes causing death. Because colonies can be massive and hidden underground, eradication is difficult and expensive.

Cactus Moth (Cactoblastis cactorum)
Originally introduced as a biological control agent in some places, this moth now threatens native cacti in the U.S., especially in the southwestern states. Larvae bore into cactus pads, destroying tissue, and reducing the ability of cacti to reproduce. As many cacti reproduce via seeds stored in their tissue or via pad fragmentation, the moth’s damage can severely reduce recruitment of new plants.

Light Brown Apple Moth (Epiphyas postvittana)
This moth feeds on a very broad host range of fruit crops, ornamentals, and vegetables. Its larvae chew on leaves, fruit, and buds, damaging yield and quality. Because of quarantine restrictions in many regions, its presence affects trade, nursery production, and agricultural operations.

Pink Hibiscus Mealybug (Maconellicoccus hirsutus)
This pest infests a variety of ornamental and crop plants, injecting toxic saliva while feeding, which weakens or kills the plant. It also produces honeydew, encouraging sooty mold growth that reduces photosynthesis and plant vigor. The mealybug’s broad host range and rapid reproduction make it a persistent threat to horticulture and agriculture.

Citrus Longhorned Beetle (Anoplophora chinensis)
This wood-boring beetle is a serious pest of citrus and many ornamental trees. Larvae tunnel deep into wood, disrupting vascular tissues, weakening the structural integrity of trees, and eventually killing them. Infestations often require tree removal, quarantines, and costly eradication measures.

European Gypsy Moth (Lymantria dispar)
This defoliating moth attacks a wide variety of tree species, particularly oaks. Caterpillars strip leaves, weakening trees, reducing growth, and sometimes leading to mortality. Repeated defoliation reduces acorn production, thereby affecting seed production of native hardwoods. Gypsy moth outbreaks also shift forest species composition by favoring species that can better tolerate defoliation.

Asian Longhorned Tick (Haemaphysalis longicornis)
This tick species is a vector of disease and poses a threat to livestock, wildlife, and possibly humans. Its rapid reproduction and ability to reproduce parthenogenetically in some cases make it especially invasive. The tick feeds on a broad host range, increasing its potential to spread disease.

4. Invasive Plants

Kudzu (Pueraria montana var. lobata)
Often called “the vine that ate the South,” kudzu grows aggressively, climbing and smothering trees, shrubs, and structures. It spreads rapidly, forming dense mats that shade out native vegetation, reducing biodiversity, and altering ecosystem function. In natural areas, it can dominate light gaps, preventing native plants from establishing seedlings and producing seeds.

Tree‑of‑Heaven (Ailanthus altissima)
This fast-growing tree thrives in disturbed soils and urban environments. It produces large amounts of seeds that are easily dispersed by wind. Its rapid growth and allelopathic chemicals suppress surrounding native plants. Because it establishes quickly and tolerates poor soils, it outcompetes native species, reducing seedling recruitment of more desirable trees.

Chinese Tallowtree (Triadica sebifera)
Also known as the popcorn tree, this species produces abundant seeds encased in a waxy coating that facilitates dispersal. It invades floodplains, wetlands, and upland forests, displacing native plants. The dense stands it forms shade out understory species, suppressing the growth and seed production of natives.

Nepalese Browntop / Japanese Stiltgrass (Microstegium vimineum)
This grass spreads rapidly in forest understories, forming thick mats that suppress native groundcover. Its prolific seed production and ability to germinate in low-light conditions make it a formidable competitor. Native plants struggle to survive, reducing seed diversity and altering the seed bank.

Cogongrass (Imperata cylindrica)
One of the most destructive grasses in the U.S., cogongrass spreads by rhizomes and seeds. It increases fire risk because it dries out and becomes highly flammable. After burning, it quickly resprouts, outcompeting native vegetation. Its dominance disrupts native plant communities and reduces opportunities for native seeds to establish.

Hydrilla (Hydrilla verticillata)
This aquatic plant forms dense mats at the surface of water bodies, shading out native submerged plants. It reproduces through fragments, tubers, and turions, making eradication difficult. Hydrilla impairs water flow, reduces oxygen levels, and degrades habitats for fish and invertebrates.

European Watermilfoil (Myriophyllum spicatum)
Another aquatic invader, watermilfoil grows rapidly and forms thick, tangled mats that crowd out native vegetation. It reproduces via fragments and can regrow from small pieces broken off by boats or water movement. Dense milfoil stands reduce light penetration, degrade habitat, and interfere with recreation.

Garlic Mustard (Alliaria petiolata)
This understory plant spreads aggressively in forests across the U.S. Its prolific seed production and allelopathic compounds inhibit the growth of native plants. As it spreads, it reduces the diversity of native wildflowers and groundcovers, altering the seed bank and forest regeneration.

Japanese Knotweed (Fallopia japonica / Polygonum cuspidatum)
This shrub-like perennial is highly resilient. It spreads via rhizomes and seeds, forming dense thickets that exclude native vegetation. Its presence along waterways contributes to bank erosion and suppresses the regeneration of native trees and shrubs, reducing seedling recruitment of native species.

Multiflora Rose (Rosa multiflora)
Originally introduced as a rootstock and for erosion control, multiflora rose formed impenetrable thickets in fields, forest edges, and pastures. It produces large quantities of rose hips (seeds), facilitating rapid spread. These dense thickets outcompete native shrubs and prevent native herbaceous plants from producing seeds.

Oriental Bittersweet (Celastrus orbiculatus)
This climbing vine wraps around trees, eventually girdling them. It produces abundant seeds encased in berries, facilitating spread via birds and mammals. As it climbs, it suppresses canopy trees, reduces light for native understory species, and compromises forest regeneration, limiting the recruitment of native seedlings.

Purple Loosestrife (Lythrum salicaria)
This wetland plant crowds out native marsh species through dense growth and prolific seed production. One plant can produce hundreds of thousands of seeds, which spread easily through water. Its dominance transforms wetland ecosystems, reducing native diversity and altering hydrology.

Spotted Knapweed (Centaurea stoebe)
Highly competitive on rangelands, this knapweed uses allelopathy to inhibit native plants. It produces large numbers of seeds, many of which persist in the soil seed bank. As it spreads, it reduces forage for wildlife and livestock and degrades native plant communities.

Water Chestnut (Trapa natans)
An aquatic plant that forms dense floating mats, water chestnut shades the water surface, depletes oxygen, and interferes with recreation and boating. It produces buoyant seeds that remain viable for years, allowing rapid colonization.

Glossy Buckthorn (Frangula alnus)
This shrub invades wetlands, woodlands, and riparian zones. It produces dark berries eaten by birds, which disperse seeds widely. Once established, it shades out native shrubs and herbaceous plants, reducing seedling establishment and seed diversity in the understory.

Black Swallowwort (Cynanchum louiseae)
This vine produces pods full of wind-dispersed seeds. Once germinated, it forms dense mats, smothering native plants. Its toxicity makes it unappealing to many herbivores, giving it a further advantage in ecosystems not adapted to its presence.

Bush Honeysuckle (Lonicera spp.)
Several non-native honeysuckle species produce abundant berries that promote rapid spread. These shrubs form dense thickets, shading out native groundcover and reducing the reproductive success of forest herbs and shrubs by limiting light, space, and pollinator access.

Autumn Olive (Elaeagnus umbellata)
This nitrogen-fixing shrub produces many fleshy fruits which are eaten by birds, helping to disperse its seeds. Once established, it improves soil nitrogen levels enough to alter plant community composition, often to the detriment of native species that depend on nutrient-poor soils.

Brazilian Peppertree (Schinus terebinthifolius)
This tropical invasive shrub or small tree is widespread in southern U.S. habitats. It produces abundant seeds in fleshy drupes consumed by birds. When it dominates, it crowds out native plants, displaces native trees, and alters ecosystem dynamics in coastal and inland habitats.

Brazilian Waterweed (Egeria densa)
Another aquatic invader, this plant forms dense underwater growth. It spreads via fragmentation; even small pieces can root and grow, making removal difficult. Dense infestations choke waterways, reduce native aquatic plant biomass, and lower water quality.

Nutgrass (Cyperus rotundus)
Also known as purple nutgrass, this sedge is one of the world’s worst weeds. It grows via tubers and produces seeds that persist in soil. Its deep rhizome system makes it hard to eradicate, and it competes aggressively with crops and native plants, reducing yield and biodiversity.

West Indian Marsh Grass (Hymenachne amplexicaulis)
This grass thrives in wetland environments, forming dense stands that displace native vegetation. It spreads via rhizomes and seeds, and its large biomass can change water flow, light penetration, and nutrient dynamics in invaded wetlands.

5. Pathogens & Diseases

Chestnut Blight (Cryphonectria parasitica)
This fungal pathogen eradicated mature American chestnut trees in eastern forests during the 20th century. It infects bark and cambium, girdling and killing trees, so mature seed-producing chestnuts essentially disappeared in the wild. The loss of these keystone trees drastically altered forest composition, the seed bank, and the availability of nuts for wildlife.

Dutch Elm Disease (Ophiostoma spp.)
Spread by bark beetles, Dutch elm disease has decimated American elms. Infested trees are girdled, weakening and eventually killing them. The loss of elms altered urban and forest landscapes, impacting seed production of elms and associated species and reducing the structural diversity of forests.

Sudden Oak Death (Phytophthora ramorum)
This oomycete pathogen infects oaks and other species, causing cankers, bleeding lesions, and high mortality. Its spread threatens forest regeneration by killing seed-bearing trees. As mature trees die, seed inputs to the forest decline, impairing natural recruitment and shifting species composition.

White Pine Blister Rust (Cronartium ribicola)
This fungal disease infects white pines, killing branches and mature trees over time. The loss of white pines reduces their seed production and the contribution of pine seeds to forest regeneration. It also affects forest structure, as fewer healthy pines remain to reach reproductive age.

Beech Leaf Disease / Beech Leaf Disorder (e.g., Litylenchus crenatae mccannii)
This nematode (or associated pathogen) causes major damage to beech trees, reducing vigor and increasing mortality. As adult beech trees decline, fewer beech nuts (seeds) are produced for wildlife and for future forest regeneration. This can shift the balance of forest species over time, degrading seed‑based recruitment dynamics.

Asian Swine Fever Virus
This viral pathogen does not directly attack plants, but its presence can influence invasive mammal populations (e.g., wild pigs) and management strategies. While not directly related to seed production, it exacerbates the ecological and economic challenges associated with the wild pig invasion and complicates control efforts that indirectly affect ecosystems.

6. Impacts on Seed Production and Seed Quality

Of the 50 species listed, only a subset directly affects seed production or seed quality. The most significant indirect effects come from invasive plants and large-scale tree-killing insects and pathogens. For example, tree-of-heaven, Japanese knotweed, and Chinese tallowtree outcompete native seed-producing plants by dominating light, soil, and space, which limits native seedling recruitment. Multiflora rose and oriental bittersweet produce abundant seeds, increasing their own spread while reducing the opportunity for native species to regenerate.

In the realm of pathogens, chestnut blight effectively wiped out mature American chestnut trees, halting the production of chestnuts (seeds) in forest ecosystems that once relied on them. White pine blister rust suppresses seed production in white pines by killing branches and reducing reproductive health, while sudden oak death decreases the number of mature oaks able to produce acorns. In this way, invasive pathogens can erode the seed bank of native species, reducing genetic diversity and long-term resilience.

Moreover, when invasive herbivores such as nutria destroy root systems and above-ground vegetation, they destabilize plant populations, erode soils, and fragment habitat—factors that indirectly undermine seedling establishment and seed production in native plant communities. While nutria do not directly consume seeds as their primary food source, the ecosystem-level damage they cause can impair native plants’ ability to set seed.

7. Economic & Ecological Consequences of Key Species

Some invasive species cause disproportionately large economic or ecological damage. The emerald ash borer, for example, is responsible for an estimated $10.7 billion in costs over a 10-year period in tree removal, treatment, and replacement in U.S. communities. Local governments face additional millions of dollars in annual expenditures, and property values decline significantly as infested trees die. The widespread loss of ash also damages urban canopy cover, ecosystem services, and biodiversity.

For nutria, their burrowing often spans hundreds of feet, undermining flood-control structures, levees, and irrigation systems. Damage to marshes has permanent ecological consequences, as wetland loss reduces habitat for fish, invertebrates, and birds. Their feeding behavior destabilizes soils, and the erosion that follows imposes high costs for restoration. They also threaten agricultural crops — in some regions, they damage rice, corn, and other field crops — leading to agricultural losses and increased management costs.

In the aquatic realm, lionfish not only deplete reef fish populations but also undermine reef resilience, affecting tourism, fishing, and ecosystem services. Northern snakehead populations threaten native freshwater fish communities, potentially disrupting local fisheries and biodiversity.

Among plants, kudzu and cogongrass are ecological nightmares: kudzu’s rampant growth chokes out native species, while cogongrass fuels wildfire risk and spreads aggressively. These invasions can shift ecosystem trajectories, making restoration costly and complex.

The pathogen-driven collapse of American chestnut due to chestnut blight had profound ecological effects. The loss of this keystone species reshaped forest composition, eliminated a major source of nuts for wildlife, and removed a tree that historically contributed substantially to forest structure and seed production.

8. Management & Control Efforts

Managing high-impact invasive species requires multifaceted strategies tailored to each species’ biology, ecology, and spread mechanisms. For nutria, control programs often involve trapping, population management, and habitat modification. On the Delmarva Peninsula, a large-scale eradication project has successfully removed nutria from sensitive marsh areas, followed by marsh restoration to encourage recovery of native vegetation.

To combat emerald ash borer, agencies use a combination of insecticide treatment, removal of infested trees, and biological control. Quarantine zones restrict the movement of firewood and ash materials to slow spread. Research into parasitoids and resistant ash varieties continues, along with public education about early detection.

Spotted lanternfly control relies heavily on preventing egg mass spread, scraping and destroying egg masses, applying insecticides, and using barrier traps. Regulatory measures and community outreach are also key parts of suppression strategies.

In aquatic systems, lionfish control has included targeted removals — spear fishing, derbies, and commercial harvesting — to reduce local populations. Public engagement and consumer demand for lionfish as food help sustain removal efforts.

For invasive plants, integrated management includes mechanical removal (cutting, mowing), chemical control (herbicide application), and in some cases, biological control agents. Restoration of native species after removal is critical to prevent reinvasion. In fire-prone invasions like cogongrass, controlled burns are used alongside herbicide application.

Pathogen control, such as for sudden oak death, involves quarantines, removal of infected trees, and limiting movement of high-risk plants. Breeding programs for disease resistance (e.g., chestnut blight) aim to restore key tree species.

Public education, policy (quarantines, regulations), early detection, and rapid response are common themes across all management programs. Long-term success often depends not just on eradication but on ecosystem restoration, monitoring, and community involvement.

9. Conclusion

The 50 invasive species outlined here represent a diverse but deeply interlinked set of threats to U.S. ecosystems, economy, and long-term ecological resilience. From rodents that erode marshes to insects that kill mature trees, plants that outcompete natives, and diseases that wipe out keystone species, these invaders undermine habitat function, biodiversity, and ecosystem services. While not all directly affect seed production, many disrupt the conditions necessary for native plants to reproduce or reduce the abundance of seed-bearing species.

Managing these high-impact invaders is critical. Success requires sustained, coordinated efforts that combine science, public policy, on-the-ground removal, restoration, and prevention. Without such efforts, the seeds of native biodiversity may struggle to find root, threatening both ecological integrity and the natural heritage of future generations.

Citations

1. U.S. Fish & Wildlife Service. Nutria Eradication Project.
2. California Department of Fish and Wildlife. California’s Invaders: Nutria.
3. U.S. Fish & Wildlife Service. Ecological Risk Screening Summary: Nutria (Myocastor coypus).
4. USDA APHIS. Operational Activities: Nutria.
5. U.S. Geological Survey. Modeling the effects of nutria (Myocastor coypus) on wetland loss.
6. Maryland Sea Grant / UMD. Aquatic Invasive Species: Nutria brief.
7. Columbia University Invasion Biology Summary Project. Myocastor coypus.
8. USDA Forest Service. Local government, homeowners paying price for non-native forest insects.
9. U.S. Forest Service, Northern Research Station. Simulation study on emerald ash borer economic impacts.
10. USDA APHIS. Emerald Ash Borer Program (economic impact summary).
11. Kovacs, K. F., et al. (2011). The influence of satellite populations of emerald ash borer on projected economic damage in U.S. communities, 2010–2020.
12. Ramsfield, T., et al. (2016). Determining the economic impacts of emerald ash borer. Forestry: An International Journal of Forest Research.