The Complete List of Invasive Species In Tennessee

Tennessee’s landscape is a vibrant tapestry, from the majestic Great Smoky Mountains to the rich lowlands along the Mississippi. This incredible biodiversity is a source of pride, yet it faces constant threats from external forces, particularly those that disrupt its delicate balance.

To help shed light on one of these critical challenges, we’ve compiled a definitive resource. Below, you’ll find a list detailing 86 Invasive Species in Tennessee, showcasing a wide range from the pervasive Air Potato to the aquatic Zebra Mussel. For each, we’ve organized essential information by its Scientific Name, Type, Primary Impact, and Origin, offering a comprehensive look at these ecological disruptors.

What exactly is an invasive species?

An invasive species is defined as a non-native organism (animal, plant, or microorganism) that, when introduced to a new ecosystem, causes or is likely to cause economic or environmental harm or harm to human health. Unlike simply non-native species, invasives aggressively outcompete local flora and fauna, disrupt food webs, and can drastically alter habitats, threatening biodiversity.

Why is it important to monitor invasive species in Tennessee?

Monitoring Invasive Species in Tennessee is critical for protecting the state’s unique ecosystems and economic interests. Early detection allows for more effective control and eradication efforts, preventing widespread ecological damage, preserving native wildlife and plant populations, and safeguarding industries like agriculture, forestry, and tourism, which can be severely impacted by these intruders.

Invasive Species in Tennessee

Common Name	Scientific Name	Type	Primary Impact	Origin
Kudzu	Pueraria montana	Plant	Smothers and kills native trees and vegetation by blocking all sunlight.	East Asia
Emerald Ash Borer	Agrilus planipennis	Insect	Larvae feed under bark, killing nearly all North American ash tree species.	Northeastern Asia
Feral Hog	Sus scrofa	Mammal	Destroys crops and native habitats with destructive rooting behavior; can spread disease.	Eurasia
Silver Carp	Hypophthalmichthys molitrix	Fish	Outcompetes native fish for plankton and poses a physical danger by leaping from water.	China
Zebra Mussel	Dreissena polymorpha	Mollusk	Clogs water intake pipes and outcompetes native mussels for food and habitat.	Eastern Europe (Caspian Sea region)
Bush Honeysuckle	Lonicera maackii	Plant	Forms dense thickets that shade out native wildflowers and prevent forest regeneration.	East Asia
Spotted Lanternfly	Lycorma delicatula	Insect	Damages crops and trees by feeding on sap; secretes sticky “honeydew” promoting mold.	China
Tree-of-Heaven	Ailanthus altissima	Plant	Releases chemicals that inhibit other plants; is the preferred host for Spotted Lanternfly.	China
Chinese Privet	Ligustrum sinense	Plant	Forms impenetrable thickets in forest understories, displacing nearly all native vegetation.	China
Hemlock Woolly Adelgid	Adelges tsugae	Insect	Sucks sap from hemlock trees, leading to needle loss and eventual tree death.	East Asia (Japan)
Garlic Mustard	Alliaria petiolata	Plant	Releases chemicals that disrupt soil fungi essential for native tree seedling survival.	Europe
Japanese Stiltgrass	Microstegium vimineum	Plant	Forms dense mats in shaded areas, smothering native plants and inhibiting tree regeneration.	East Asia
Brown Marmorated Stink Bug	Halyomorpha halys	Insect	Feeds on a wide variety of agricultural crops; becomes a major household nuisance.	East Asia
Bighead Carp	Hypophthalmichthys nobilis	Fish	A massive filter feeder that strips the food web of plankton, starving native fish.	China
Northern Snakehead	Channa argus	Fish	A voracious top predator that can displace native fish species and alter ecosystems.	East Asia
Red Imported Fire Ant	Solenopsis invicta	Insect	Delivers painful, venomous stings and builds large mounds that damage equipment.	South America
Mimosa Tree	Albizia julibrissin	Plant	Invades roadsides and riverbanks, forming dense stands that displace native vegetation.	Asia (Iran to Japan)
Bradford Pear	Pyrus calleryana ‘Bradford’	Plant	Cross-pollinates with other varieties, creating thorny, invasive thickets that choke out native species.	China, Vietnam
Multiflora Rose	Rosa multiflora	Plant	Creates dense, impenetrable thorny thickets that degrade pastureland and wildlife habitat.	Japan, Korea, China
Japanese Honeysuckle	Lonicera japonica	Plant	A climbing vine that smothers and strangles small trees and native understory plants.	East Asia
Chestnut Blight	Cryphonectria parasitica	Fungus	Functionally eliminated the American chestnut, a keystone tree species, from eastern forests.	Asia
Round Goby	Neogobius melanostomus	Fish	Aggressively competes with native bottom-dwelling fish for food and spawning sites.	Black and Caspian Seas
English Ivy	Hedera helix	Plant	Forms a dense “ivy desert” on forest floors and smothers trees.	Europe, Western Asia
Wintercreeper	Euonymus fortunei	Plant	Forms a dense groundcover that eliminates native wildflowers; can climb and smother trees.	East Asia
Princess Tree	Paulownia tomentosa	Plant	Extremely fast-growing tree that colonizes disturbed areas, displacing native pioneer species.	China
Didymo (Rock Snot)	Didymosphenia geminata	Algae	Forms thick, disgusting brown mats on river bottoms, smothering habitat for aquatic insects.	Northern Hemisphere (invasive strains)
Chinese Yam	Dioscorea oppositifolia	Plant	Vines climb high into trees, weighing them down and blocking sunlight from the forest floor.	China
Japanese Knotweed	Reynoutria japonica	Plant	Forms dense monocultures with a root system that can damage pavement and foundations.	East Asia
Spongy Moth	Lymantria dispar	Insect	Caterpillars can defoliate and kill hundreds of species of hardwood trees and shrubs.	Eurasia
Autumn Olive	Elaeagnus umbellata	Plant	Outcompetes native plants by fixing nitrogen, altering soil chemistry for its own benefit.	East Asia
Sericea Lespedeza	Lespedeza cuneata	Plant	Forms dense stands in open areas, displacing native grasses and forbs.	East Asia
Cogongrass	Imperata cylindrica	Plant	Forms dense, circular stands that exclude all other vegetation and are highly flammable.	Southeast Asia
Porcelain Berry	Ampelopsis brevipedunculata	Plant	A vigorous vine that smothers shrubs and small trees under a dense blanket of leaves.	Northeast Asia
Oriental Bittersweet	Celastrus orbiculatus	Plant	Twines tightly around trees, girdling their trunks and weighing down canopies.	East Asia
New Zealand Mud Snail	Potamopyrgus antipodarum	Mollusk	Reaches enormous densities, outcompeting native snails and insects for food.	New Zealand
Rusty Crayfish	Faxonius rusticus	Crustacean	Aggressively displaces native crayfish and destroys aquatic plant beds with its foraging.	Ohio River Basin (invasive in TN streams)
Nutria	Myocastor coypus	Mammal	Destroys wetland habitats and riverbanks by eating native plants and burrowing.	South America
Dogwood Anthracnose	Discula destructiva	Fungus	Causes leaf spots, stem cankers, and dieback in flowering dogwood trees, a state symbol.	Origin uncertain, likely Asia
Thousand Cankers Disease	Geosmithia morbida	Fungus	A fungal disease spread by the Walnut Twig Beetle that is lethal to black walnut trees.	Western United States
Common Reed	Phragmites australis	Plant	Forms massive, dense stands in wetlands, crowding out native vegetation like cattails.	Eurasia (invasive subspecies)
Amur Corktree	Phellodendron amurense	Plant	Spreads into forests, creating dense shade that inhibits the growth of native seedlings.	Eastern Asia
Japanese Spirea	Spiraea japonica	Plant	Forms dense stands along streams and forest edges, displacing native shrubs and herbs.	Japan, China, Korea
Periwinkle	Vinca minor	Plant	Forms a dense, evergreen mat on the forest floor, completely smothering native wildflowers.	Europe, Southwest Asia
Asian Longhorned Beetle	Anoplophora glabripennis	Insect	Larvae tunnel deep into hardwood trees, eventually killing them. Prefers maples.	East Asia
Spiny Water Flea	Bythotrephes longimanus	Crustacean	A predatory zooplankton that alters food webs and fouls fishing lines with its long tail spine.	Northern Europe, Asia
Asian Tiger Mosquito	Aedes albopictus	Insect	An aggressive daytime biter that can transmit numerous diseases like West Nile virus.	Southeast Asia
Callery Pear	Pyrus calleryana	Plant	The species name for ornamental pears like ‘Bradford’ that create invasive thickets.	China, Vietnam
Hydrilla	Hydrilla verticillata	Plant	Forms dense underwater mats that choke waterways, block sunlight, and impede recreation.	Asia
Parrot Feather	Myriophyllum aquaticum	Plant	An aquatic plant that forms dense mats, clogging waterways and shading out native aquatic plants.	Amazon River Basin
Yellow Flag Iris	Iris pseudacorus	Plant	Forms dense colonies in wetlands and along shorelines, displacing native wetland vegetation.	Europe, Western Asia, North Africa
Eurasian Watermilfoil	Myriophyllum spicatum	Plant	Forms dense underwater canopies, crowding out native plants and hindering recreational activities.	Europe, Asia, North Africa
Curly Pondweed	Potamogeton crispus	Plant	Grows early in the season, forming dense mats that die back, causing oxygen depletion.	Eurasia
Purple Loosestrife	Lythrum salicaria	Plant	Dominates wetlands, marshes, and stream banks, replacing native vegetation.	Eurasia
Beefsteak Plant	Perilla frutescens	Plant	Invades shady, moist bottomlands and stream banks, displacing native herbaceous plants.	East Asia
Japanese Hops	Humulus japonicus	Plant	A fast-growing vine that smothers low-growing vegetation and small trees along riverbanks.	East Asia
Mile-a-Minute Weed	Persicaria perfoliata	Plant	Grows incredibly fast, smothering young trees, native plants, and reforestation projects.	India, East Asia
Russian Olive	Elaeagnus angustifolia	Plant	Outcompetes native vegetation along rivers and streams, forming dense, thorny thickets.	Europe and Asia
Saltcedar	Tamarix spp.	Plant	Consumes large amounts of water, dries up soils, and deposits salt on the surface.	Eurasia
Sweet Autumn Clematis	Clematis terniflora	Plant	A vigorous vine that can completely cover and smother native trees and shrubs.	Japan, China
Norway Maple	Acer platanoides	Plant	Creates dense shade that is too dark for native maple seedlings and wildflowers to grow.	Europe
Siberian Elm	Ulmus pumila	Plant	Invades prairies and open lands, outcompeting native grasses and shrubs.	Eastern Asia
White Mulberry	Morus alba	Plant	Hybridizes with the native Red Mulberry, threatening the genetic integrity of the native species.	China
Japanese Barberry	Berberis thunbergii	Plant	Forms dense, spiny thickets in forests and creates ideal habitat for ticks.	Japan
Burning Bush	Euonymus alatus	Plant	Invades forests and fields, forming dense thickets that shade out native plants.	Northeast Asia
Chocolate Vine	Akebia quinata	Plant	A fast-growing vine that smothers and kills shrubs and trees.	East Asia
Liriope (Monkey Grass)	Liriope muscari / spicata	Plant	Spreads from gardens into forests, forming a dense monoculture that displaces native flora.	East Asia
Golden Bamboo	Phyllostachys aurea	Plant	An extremely aggressive running bamboo that forms dense, impenetrable groves.	Southeast China
Daphne Spurge	Daphne laureola	Plant	An evergreen shrub that invades forests, forming dense stands. All parts are highly toxic.	Europe, North Africa
Chinese Silvergrass	Miscanthus sinensis	Plant	Forms large, dense clumps that displace native vegetation and create a fire hazard.	East Asia
Air Potato	Dioscorea bulbifera	Plant	A highly aggressive vine that smothers native vegetation, including mature trees.	Asia, Africa
Goldfish	Carassius auratus	Fish	Can disrupt aquatic ecosystems by stirring up sediment and preying on native invertebrates.	East Asia
Rock Bass (Shadow Bass)	Ambloplites rupestris	Fish	Invasive outside its native TN range, it outcompetes and preys on native fish.	Native to East TN, invasive in Central/West
White Perch	Morone americana	Fish	A prolific fish that can outcompete native species and impact sportfish populations.	Atlantic Coast of North America
Alewife	Alosa pseudoharengus	Fish	Can outcompete young native fish for zooplankton and cause thiamine deficiency in predators.	Atlantic Coast of North America
Whirling Disease	Myxobolus cerebralis	Parasite	A microscopic parasite that deforms and kills young trout and salmon.	Eurasia
Dutch Elm Disease	Ophiostoma ulmi / novo-ulmi	Fungus	A fungal disease spread by bark beetles that has devastated American elm populations.	Asia
Laurel Wilt	Raffaelea lauricola	Fungus	A deadly disease of plants in the laurel family, spread by the redbay ambrosia beetle.	Asia
Sirex Woodwasp	Sirex noctilio	Insect	Females inject a toxic mucus and fungus while laying eggs, killing pine trees.	Europe, Asia, North Africa
Sudden Oak Death	Phytophthora ramorum	Pathogen	A water mold (oomycete) that causes lethal cankers on oaks and blights on other plants.	Origin Unknown
Viburnum Leaf Beetle	Pyrrhalta viburni	Insect	Larvae and adults skeletonize the leaves of viburnum shrubs, eventually killing them.	Europe
Beech Bark Disease	Nectria coccinea faginata	Disease Complex	An insect-fungus complex that kills mature American beech trees, altering forest composition.	Europe
Asian Needle Ant	Brachyponera chinensis	Insect	A venomous, stinging ant that displaces native ants and can cause allergic reactions.	East Asia
Common House Sparrow	Passer domesticus	Bird	Aggressively displaces native cavity-nesting birds like bluebirds and swallows from nest sites.	Eurasia
European Starling	Sturnus vulgaris	Bird	Outcompetes native birds for nest cavities and forms massive, noisy, and messy roosts.	Eurasia
Rock Pigeon	Columba livia	Bird	Their droppings can damage buildings and pose a health risk in urban areas.	Europe, North Africa, Middle East
Mute Swan	Cygnus olor	Bird	Aggressively defends territory, displacing native waterfowl. Overgrazes aquatic vegetation.	Eurasia

Images and Descriptions

Kudzu

A notoriously fast-growing vine with large, three-lobed leaves. It can grow up to a foot a day, completely blanketing trees, buildings, and utility poles in a dense green carpet.

Emerald Ash Borer

A small, jewel-like metallic green beetle. While the adults cause little damage, their D-shaped exit holes are a key sign of a deadly infestation by their destructive larvae.

Feral Hog

A highly intelligent and adaptable wild pig with coarse hair and sharp tusks. They travel in groups called sounders and can cause immense agricultural and ecological damage overnight.

Silver Carp

A large, deep-bodied fish known for its startling habit of jumping high out of the water when disturbed by boat motors. They are voracious filter feeders that disrupt aquatic food webs.

Zebra Mussel

A tiny, D-shaped freshwater mussel with alternating light and dark stripes. They attach to hard surfaces in massive, dense colonies, causing major biofouling problems for infrastructure.

Bush Honeysuckle

A large, multi-stemmed shrub with arching branches and fragrant, white-to-yellow flowers. Its early leaf-out and late leaf-drop give it a competitive advantage over native plants.

Spotted Lanternfly

A visually striking planthopper with gray, spotted forewings and vibrant red hindwings. Despite its beauty, it’s a major pest of grapevines, fruit trees, and hardwoods like maple.

Tree-of-Heaven

A fast-growing tree with large, compound leaves that resemble sumac. It has a strong, unpleasant odor often compared to rancid peanut butter and spreads aggressively through suckers.

Chinese Privet

A semi-evergreen shrub with small, dark green leaves and clusters of small white flowers. It is one of the most problematic invasive plants in Tennessee’s forests and bottomlands.

Hemlock Woolly Adelgid

A tiny, aphid-like insect that covers itself with a white, waxy “wool” for protection. This pest is responsible for the widespread decline of Eastern and Carolina hemlocks.

Garlic Mustard

A biennial herb that dominates forest floors. In its first year, it’s a low rosette; in its second, it bolts up with white flowers. Crushed leaves smell strongly of garlic.

Japanese Stiltgrass

A sprawling, shade-tolerant annual grass with a distinctive silvery, off-center stripe down its pale green leaves. It rapidly colonizes disturbed areas, trails, and forest floors.

Brown Marmorated Stink Bug

A shield-shaped insect with a mottled brownish-gray color. It is known for its ability to damage fruit and for invading homes in large numbers during the fall to overwinter.

Bighead Carp

Similar to Silver Carp but even larger, with a distinctly large head and downward-facing eyes. They are a primary component of the “Asian Carp” threat to Tennessee’s large river systems.

Northern Snakehead

A long-bodied, predatory fish with sharp teeth and a snake-like pattern. It can breathe air, allowing it to survive on land for short periods and move between water bodies.

Red Imported Fire Ant

An aggressive reddish-brown ant that swarms to attack any disturbance to its mound. Its sting causes a painful pustule and can be dangerous to humans, pets, and wildlife.

Mimosa Tree

A small, umbrella-shaped tree prized for its feathery, fern-like leaves and fragrant, pink, pom-pom-like flowers. It spreads prolifically via long-lived seeds.

Bradford Pear

A once-popular ornamental tree with weak branches and showy white spring blossoms. Its offspring revert to a wild, thorny form that creates impenetrable and ecologically sterile stands.

Multiflora Rose

A vigorous, climbing shrub that can form massive mounds. It features clusters of small, fragrant white flowers and is armed with sharp, curved thorns, making it difficult to control.

Japanese Honeysuckle

A common, sweet-smelling vine with paired, oval leaves and tubular white-to-yellow flowers. It grows aggressively, twining around other plants and forming dense groundcover that eliminates native species.

Chestnut Blight

A devastating fungal pathogen that enters wounds in the bark of chestnut trees. It creates cankers that girdle and kill the tree, forever changing the composition of Appalachian forests.

Round Goby

A small, mottled brown fish with a large head and a unique, single pelvic fin shaped like a suction cup. It is a prolific breeder and can survive in poor water quality.

English Ivy

A popular evergreen climbing vine with waxy, dark green leaves. When it escapes cultivation, it smothers ground vegetation and can weigh down and kill mature trees by blocking sunlight.

Wintercreeper

An evergreen vine or shrub with glossy, dark green leaves, often used as an ornamental groundcover. It spreads relentlessly, carpeting forest floors and strangling trees it climbs.

Princess Tree

A medium-sized tree with very large, heart-shaped leaves and showy, pale violet flowers in spring. Its rapid growth and prolific seeding allow it to quickly dominate open areas.

Didymo (Rock Snot)

A microscopic diatom (algae) that can bloom into massive growths that look like wet wool or toilet paper. It thrives in cold, clear water and degrades fish habitat.

Chinese Yam

A fast-growing vine with distinctive heart-shaped leaves and small, bulb-like tubers (bulbils) on its stems. These bulbils fall to the ground and start new plants, allowing it to spread quickly.

Japanese Knotweed

A tall, bamboo-like perennial plant with hollow stems and large, spade-shaped leaves. It spreads through a powerful rhizome system, making it incredibly difficult to eradicate once established.

Spongy Moth

Formerly known as the Gypsy Moth, its voracious caterpillars feed in massive groups. During outbreak years, they can strip entire forests of their leaves, stressing and killing trees.

Autumn Olive

A large shrub with silvery-green leaves and small, tart red berries. Though its berries are eaten by birds, it aggressively colonizes open areas and meadows, shading out native plants.

Sericea Lespedeza

An upright perennial forb with slender stems and small, three-part leaves. It was once planted for erosion control but is now a major pest in pastures, prairies, and natural meadows.

Cogongrass

A perennial grass known for its fluffy, white, plume-like seed heads and off-center midrib. It creates a serious fire hazard and displaces native plants in open habitats.

Porcelain Berry

A deciduous, woody vine related to grapes. It is easily identified in the fall by its distinctive, multicolored berries that shift from pale lilac to bright turquoise and blue.

Oriental Bittersweet

A woody vine that can be distinguished from its native counterpart by its yellow fruit capsules. It grows into the tops of trees, shading them out and making them susceptible to wind damage.

New Zealand Mud Snail

A tiny aquatic snail, often no larger than a grain of rice. It reproduces asexually, allowing a single snail to start a new population that can number in the hundreds of thousands per square meter.

Rusty Crayfish

A large, aggressive crayfish identified by two rusty-colored spots on its carapace. It negatively impacts fish populations by eating their eggs and destroying the vegetation they use for cover.

Nutria

A large, semi-aquatic rodent often mistaken for a beaver, but with a round, rat-like tail. Their intensive feeding on marsh vegetation can convert healthy wetlands into open water.

Dogwood Anthracnose

A fungal disease that severely impacts dogwoods, especially those in cool, moist, shaded locations. It can kill trees and has caused significant mortality in mountain forests.

Thousand Cankers Disease

This disease results from the combined activity of a tiny beetle and the fungus it carries. The fungus creates numerous small cankers under the bark, eventually killing valuable black walnut trees.

Common Reed

A tall, perennial grass that can reach 15 feet in height and grows in dense stands along shorelines and in marshes. Its invasive form creates monocultures with little value for local wildlife.

Amur Corktree

A deciduous tree with deeply furrowed, corky bark and compound leaves. It is a prolific seed producer, and the berries are spread by birds, allowing it to invade forest edges and interiors.

Japanese Spirea

A small, deciduous shrub with clusters of small pink flowers. It is a popular landscaping plant that has escaped cultivation to form dense thickets in natural areas.

Periwinkle

A trailing, vine-like plant with glossy dark green leaves and small purple-blue flowers. Often used as an ornamental groundcover, it escapes into forests where it chokes out all other low-growing plants.

Asian Longhorned Beetle

A large, shiny black beetle with white spots and long, banded antennae. Its large, circular exit holes are a key sign of infestation. It poses a major threat to urban and forested maple trees.

Spiny Water Flea

A tiny crustacean with a very long, barbed tail spine. They eat smaller, native zooplankton, competing with young fish for food. Their spines clump up on fishing gear, causing problems for anglers.

Asian Tiger Mosquito

A small black mosquito with distinctive white stripes on its legs and body. It breeds in small containers of standing water and has become a major pest in residential areas across the state.

Callery Pear

This is the parent species of the infamous Bradford pear. Various cultivars cross-pollinate, producing offspring with large thorns that form impenetrable, ecologically damaging stands in old fields and forest edges.

Hydrilla

An aquatic plant that is considered one of the worst invasive species in the world. It can grow an inch a day, completely filling the water column and altering water chemistry.

Parrot Feather

This plant has bright green, feathery leaves that emerge from the water. It can clog drainage ditches and recreational waterways, and provides poor habitat for native wildlife.

Yellow Flag Iris

A large, attractive iris with bright yellow flowers. It spreads via rhizomes and seeds, creating dense stands that can alter hydrology and reduce habitat for waterfowl and fish.

Eurasian Watermilfoil

An aquatic plant with feathery, submerged leaves. It spreads easily through fragmentation, where small pieces broken off by boats or animals can start new colonies, choking out lakes and rivers.

Curly Pondweed

An aquatic plant with distinctive, lasagna-noodle-like leaves. Its early-season growth and mid-summer decay cycle can lead to algal blooms and fish kills from low oxygen levels.

Purple Loosestrife

A tall, attractive wetland plant with a spike of bright purple flowers. A single plant can produce over 2 million seeds, allowing it to rapidly create dense, single-species stands.

Beefsteak Plant

An annual herb in the mint family with a distinct odor. It has purplish, square stems and serrated leaves. It often forms dense stands in disturbed, shady areas of forests.

Japanese Hops

An annual climbing vine with rough, sandpapery stems and five-lobed leaves. Unlike its valuable relative used for beer, this species grows in smothering, tangled masses in sunny, moist areas.

Mile-a-Minute Weed

An annual vine named for its rapid growth. It has triangular leaves, barbed stems that help it climb, and iridescent blue berries. It quickly overtakes open and disturbed areas.

Russian Olive

A shrub or small tree similar to Autumn Olive but with narrower, silvery leaves. It tolerates poor conditions and aggressively colonizes riparian zones, altering the natural plant community.

Saltcedar

A shrub or tree with small, scale-like leaves and pink or white flowers. It is a major problem in the western U.S. and has established populations in Tennessee, threatening riverbanks and wetlands.

Sweet Autumn Clematis

A climbing vine that becomes extremely noticeable in late summer when it is covered in masses of small, fragrant white flowers. It escapes gardens and can quickly overwhelm native vegetation.

Norway Maple

A common street and landscape tree that looks similar to sugar maple. Its seeds readily sprout in nearby forests, where the saplings’ dense canopy outcompetes native flora on the forest floor.

Siberian Elm

A fast-growing, drought-tolerant tree that can thrive in harsh conditions where native trees cannot. It spreads aggressively by seed and can form dense, low-value stands.

White Mulberry

Originally imported to support the silk industry. This tree is now widespread and poses a significant threat to the less common native Red Mulberry through hybridization and competition.

Japanese Barberry

A popular landscaping shrub with small leaves that can be green, yellow, or red, and small, red, oval berries. It alters soil chemistry and has been linked to higher rates of Lyme disease.

Burning Bush

A popular ornamental shrub known for its brilliant red fall foliage and winged stems. Birds eat its berries and spread the seeds into natural areas, where it can become a dominant shrub.

Chocolate Vine

A semi-evergreen woody vine with distinctive five-lobed leaves and maroon, spicy-scented flowers. It grows extremely fast, forming a thick blanket over other plants, blocking all sunlight.

Liriope (Monkey Grass)

A popular evergreen groundcover with grass-like leaves. The spreading variety, *L. spicata*, is particularly aggressive, escaping into forests where it carpets the ground and prevents native plant growth.

Golden Bamboo

This is a large, fast-spreading bamboo with golden-green canes. It escapes cultivation and can quickly take over yards, forest edges, and stream banks, displacing all other plants with its dense root mat.

Daphne Spurge

A shade-tolerant evergreen shrub with whorled, glossy green leaves. It can create dense stands in the forest understory, and its toxic nature makes it unpalatable to browsing animals.

Chinese Silvergrass

A large, popular ornamental grass with tall, feathery plumes. It readily escapes cultivation, establishing in fields and roadsides where its dense growth and dry winter foliage increase fire risk.

Air Potato

This vine is named for the potato-like growths (bulbils) on its stems. It can grow up to eight inches a day, quickly climbing to the tops of trees and forming a dense shade that kills plants below.

Goldfish

The common pet goldfish, when released into the wild, can grow quite large. They root along the bottom, which clouds the water, and compete with native fish for food resources.

Rock Bass (Shadow Bass)

A sunfish species that, when moved outside its native Tennessee River drainage, can outcompete other native sunfish and bass species for food and habitat in smaller streams.

White Perch

Not a true perch, this species is related to striped bass. They reproduce rapidly and can dominate a water body, preying on the eggs and young of more desirable game fish like walleye.

Alewife

A species of river herring that can become invasive in landlocked reservoirs. They can experience massive die-offs that foul shorelines and alter the food web for sportfish like trout and salmon.

Whirling Disease

This parasite infects the cartilage of young fish, causing them to swim in a characteristic “whirling” pattern. It can have a devastating impact on wild trout populations in affected streams.

Dutch Elm Disease

This disease is responsible for the death of millions of American elm trees across North America. The fungus clogs the tree’s vascular tissue, causing it to wilt and die.

Laurel Wilt

This fungal pathogen is a major threat to sassafras and spicebush in Tennessee. The disease causes a rapid wilting and death of the host tree once the fungus is introduced by the beetle.

Sirex Woodwasp

A large, dark-colored wasp that attacks pine trees. It is a major pest in pine plantations, as the combination of its toxic saliva and a symbiotic fungus can overwhelm and kill healthy trees.

Sudden Oak Death

While not yet widespread in Tennessee’s forests, this pathogen is under strict quarantine. It has caused widespread mortality of oak trees on the West Coast and is a major threat.

Viburnum Leaf Beetle

A small beetle that can completely defoliate native and ornamental viburnum species. Repeated defoliation over several years can weaken and ultimately kill these important native shrubs.

Beech Bark Disease

This disease begins when the beech scale insect feeds on the tree’s bark, creating wounds that are then infected by a Nectria fungus. The resulting cankers can girdle and kill the tree.

Asian Needle Ant

A slender, dark-colored ant that often lives in forested areas. Unlike many ants, it forages individually. Its sting is painful and it is a threat to native ant biodiversity.

Common House Sparrow

A small, stocky bird common in urban and agricultural areas. They are known for their aggressive behavior, often taking over nest boxes and killing the eggs and young of native birds.

European Starling

A glossy, dark bird with a speckled appearance. Introduced in the 1890s, they have spread across the continent, displacing native woodpeckers, bluebirds, and other cavity-nesters.

Rock Pigeon

The common city pigeon. While familiar, they are a non-native species. In large numbers, their acidic droppings can deface and accelerate the deterioration of stonework and historic buildings.

Mute Swan

A large, all-white swan with an S-curved neck and a bright orange bill. Despite their graceful appearance, they can be extremely aggressive towards people and other birds during nesting season.