Image Archive
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About these images
For information on image usage rights and fees, and how to attribute the photographers, go to our image inventory page. Note: Read our disclaimer regarding lists of species on our web site..
For information on image usage rights and fees, and how to attribute the photographers, go to our image inventory page. Note: Read our disclaimer regarding lists of species on our web site..
Species | Description/Photographer | |
See the previous set of photos | ||
Polygonum cuspidatum | A large plant/photo JMR | |
Polygonum cuspidatum | A branch/photo JMR | |
Polygonum cuspidatum | Flower buds/photo BAR | |
Polygonum cuspidatum | A pink plant/photo BAR | |
Polygonum cuspidatum | Pink branch/photo BAR | |
Polygonum cuspidatum | Pink flowers/photo BAR | |
Polygonum cuspidatum | Riverside/photo JMR | |
Polygonum cuspidatum | Green branches/photo MT | |
Polygonum perfoliatum | Japanese beetles/photo JMR | |
Polygonum perfoliatum | Beetle damage/photo JMR | |
Polygonum perfoliatum | Thwarted scientists/photo JMR | |
Polygonum perfoliatum | Nasty leaves/photo JMR | |
Polygonum perfoliatum | Nasty branch/photo JMR | |
Polygonum perfoliatum | A big lump/photo courtesy Bill Jacobs, bjacobs(at)tnc.org (*) | |
Polygonum perfoliatum | Climbing bushes/photo courtesy Bill Jacobs, bjacobs(at)tnc.org (*) | |
Polygonum perfoliatum | Climbing trees/photo courtesy Bill Jacobs, bjacobs(at)tnc.org (*) | |
Polypogon monspeliensis | Fuzzy flowers/photo BAR | |
Polypogon monspeliensis | Plant/photo JMR | |
Potentilla recta | Flowers/photo JMR | |
Potentilla recta | Plants/photo JMR | |
Potentilla recta | Hillside/photo Jerry Asher(*) | |
Populus nigra var. italica | Dune invasion/photo JMR | |
Populus nigra var. italica | Big trees I/photo JMR | |
Populus nigra var. italica | Big trees II/photo JMR | |
Populus nigra var. italica | Sucker/photo JMR | |
Populus nigra var. italica | Lake beyond the weeds/photo JMR | |
Prosopis pallida | Trees/photo JMR | |
Psidium cattleianum | An invasive tree/photo JMR | |
Psidium guajava | Dense tree/photo JMR | |
Psidium guajava | Leaves/photo JMR | |
Psoralea pinnata | Leaves and flowers/photo JMR | |
Psoralea pinnata | Floral close-up/photo JMR | |
Psoralea pinnata | Bush/photo JMR | |
Pueraria montana | Weird.../photo BAR | |
Pueraria montana | Weirder!/photo BAR | |
Pueraria montana | More weirder/photo BAR | |
Pueraria montana | More weirdest/photo BAR | |
Pueraria montana | Flowers/photo BAR | |
Pueraria montana | Weirdissimo.../photo JMR | |
Pueraria montana | More weird/photo JMR | |
Pueraria montana | Leaflets three/photo MT | |
Pueraria montana | Invasions--so sad/photo BAR | |
Pueraria montana | Scientist imperilled/photo MT | |
Quercus acutissima | Leaves/photo JMR | |
Quercus acutissima | Landscape tree/photo JMR | |
Ranunculus ficaria | In garden/photo MT | |
Ranunculus ficaria | Viewed closer/photo MT | |
Ranunculus ficaria | Wider view/photo MT | |
Ranunculus ficaria | In forest/Allan Lindberg (Nassau Co. Parks Dept., ajlindberg(at)verizon.net) | |
Ranunculus ficaria | Many flowers/Allan Lindberg (Nassau Co. Parks Dept., ajlindberg(at)verizon.net) | |
Ranunculus ficaria | Streamside/Allan Lindberg (Nassau Co. Parks Dept., ajlindberg(at)verizon.net) | |
Ranunculus ficaria | Stream banks/Allan Lindberg (Nassau Co. Parks Dept., ajlindberg(at)verizon.net) | |
Raphanus sativus | Bad foliage/photo JMR | |
Rhamnus cathartica | Foliage I/photo JMR | |
Rhamnus cathartica | Fruit I/photo JMR | |
Rhamnus cathartica | Orange tissue/photo JMR | |
Rhamnus cathartica | Foliage II/photo JMR | |
Rhamnus cathartica | Fruit III/photo JMR | |
Rhamnus cathartica | Fruit II/photo JMR | |
Rhamnus cathartica | Leafing out/photo JMR | |
Rhamnus cathartica | Invasion/photo JMR | |
Rhamnus frangula | Plant/photo JMR | |
Rhamnus frangula | Flowers/photo JMR | |
Rhamnus frangula | Fruit.../photo JMR | |
Rhamnus frangula | ...and more fruit/photo JMR | |
Rhamnus frangula | Twigs/photo JMR | |
Rhamnus frangula | Encroaching/photo JMR | |
Rhamnus frangula | Seedlings & resprouts/photo JMR | |
Rhodomyrtus tomentosa | Shrubs/photo JMR | |
Rhodotypos scandens | Leaves and fruit/photo JMR | |
Rhodotypos scandens | Leaves/photo JMR | |
Rhodotypos scandens | Flowers and fruit/photo Marilyn Jordan, mjordan(at)tnc.org(*) | |
Rhodotypos scandens | Shrub/photo Marilyn Jordan, mjordan(at)tnc.org(*) | |
Rhodotypos scandens | Leaves and flowers/photo Marilyn Jordan, mjordan(at)tnc.org(*) | |
Ricinus communis | Leaves/photo JMR | |
Ricinus communis | More leaves/photo JMR | |
Ricinus communis | Flowers/photo JMR | |
Ricinus communis | Autumnal bush/photo BAR | |
Ricinus communis | Toxic beans/photo BAR | |
Ricinus communis | Oceanside/photo MT | |
Rivina humilis | Leaves and fruit/photo JMR | |
Robinia pseudoacacia | Small trees/photo JMR | |
Robinia pseudoacacia | Flowers/photo JMR | |
Robinia pseudoacacia | More flowers/photo JMR | |
Robinia pseudoacacia | Flowering branch/photo JMR | |
Robinia pseudoacacia | Tree bark/photo JMR | |
Robinia pseudoacacia | Fruit/photo JMR | |
Robinia pseudoacacia | Young tree/photo JMR | |
Robinia pseudoacacia | Lone tree/photo MT | |
Robinia pseudoacacia | Dried pods I/photo MT | |
Robinia pseudoacacia | Dried pods II/photo MT | |
Romulea rosea | Sandy plant/photo JMR | |
Romulea rosea | Flower close-up/photo JMR | |
Rosa multiflora | Thorns/photo BAR | |
Rosa multiflora | Fruit/photo BAR | |
Rosa multiflora | Flowers I/photo JMR | |
Rosa multiflora | Stolon formation/photo JMR | |
Rosa multiflora | Clambering upslope/photo JMR | |
Rosa multiflora | Scientists in peril!/photo JMR | |
Rosa multiflora | Stipulate leaf/photo JMR | |
Rosa multiflora | wi/rosette disease/photo JMR | |
Rosa multiflora | Flowers II/photo JMR | |
Rosa multiflora | Big bush!/photo JMR | |
Rubus argutus | Bad! Bad!/photo JMR | |
Rubus argutus | Fruit/photo JMR | |
Rubus argutus | Flower/photo JMR | |
Rubus argutus | Ow! Ow!/photo JMR | |
Rubus armeniacus | Big plant/photo JMR | |
Rubus armeniacus | Plant/photo JMR | |
Rubus armeniacus | Yum! Yum!/photo JMR | |
Rubus armeniacus | Flowers/photo JMR | |
Rubus armeniacus | More flowers/photo JMR | |
Rubus armeniacus | Pretty flowers/photo JMR | |
Rubus armeniacus | A thorny field/photo JMR | |
Rubus armeniacus | A very thorny field/photo JMR | |
Rubus fruticosus | Sprawling/photo JMR | |
Rubus fruticosus | Spiny stems/photo JMR | |
Rubus phoenicolasius | Plants/photo JMR | |
Rubus phoenicolasius | Spiny branch/photo JMR | |
Rubus phoenicolasius | Fruit/photo JMR | |
Rubus phoenicolasius | Yum yum!/photo JMR | |
Rubus rosifolius | Plants/photo JMR | |
Rumex crispus | Inflorescence/photo JMR | |
Rumex crispus | Plants/photo JMR | |
Rumex crispus | In slough I/photo JMR | |
Rumex crispus | In slough II/photo JMR | |
Saccharum ravennae | Many culms/photo Jeffrey Firestone(*) | |
Saccharum ravennae | Snippers for scale/photo Jeffrey Firestone(*) | |
Saccharum ravennae | Hairy sheaths/photo Jeffrey Firestone(*) | |
Saccharum ravennae | Inflorescences/photo Jeffrey Firestone(*) | |
Saccharum ravennae | By a bridge/photo Jeffrey Firestone(*) | |
Saccharum ravennae | Thick infestation/photo Jeffrey Firestone(*) | |
Saccharum ravennae | Arched plumes/photo Jeffrey Firestone(*) | |
Saccharum ravennae | Tall plumes/photo Jeffrey Firestone(*) | |
Saccharum ravennae | Riverside growth/photo Jeffrey Firestone(*) | |
Saccharum ravennae | On both banks/photo Jeffrey Firestone(*) | |
Saccharum ravennae | Riparian weed/photo Jeffrey Firestone(*) | |
Salix sp. | Group of plants/photo JMR | |
Salix sp. | Hedge/photo JMR | |
Salix sp. | Shoreline plants/photo JMR | |
Salix sp. | Young plant/photo JMR | |
Salvia aethiopis | Hillside plants/photo Jerry Asher(*) | |
Salsola sp. | Choking branches/photo JMR | |
Salvinia minima | Floating plants/photo BAR | |
Salvinia minima | Gobbling a pond/photo BAR | |
Salvinia minima | Many leaves/photo BAR | |
Salvinia minima | In a bayou/photo BAR | |
Salvinia minima | Leaf close-up/photo BAR | |
Salvinia molesta | A plant/photo BAR | |
Salvinia molesta | Leaf surface/photo BAR | |
Salvinia molesta | Leaf hairs/photo BAR | |
Sapium sebiferum | Catkin/photo JMR | |
Sapium sebiferum | Looking upwards/photo MT | |
Sapium sebiferum | Young tree/photo JMR | |
Sapium sebiferum | Fruit/photo JMR | |
Sapium sebiferum | Lygodium japonicum on Sapium sebiferum/photo BAR | |
Sapium sebiferum | Infestation!/photo JMR | |
Sapium sebiferum | Don't eat the fruit!/photo BAR | |
Sapium sebiferum | Resprouts/photo JMR | |
Sapium sebiferum | Green leaves/photo JMR | |
Sapium sebiferum | Landscape tree/photo JMR | |
Saponaria officinalis | Pretty flowers/photo JMR | |
Saponaria officinalis | Whole plant/photo JMR | |
Saponaria officinalis | In dunes I/photo JMR | |
Saponaria officinalis | In dunes II/photo JMR | |
Scaevola sericea | Flowers/photo MT | |
Scaevola sericea | Flowers and fruit/photo MT | |
Scaevola sericea | Many fruit/photo MT | |
Scaevola sericea | Plant/photo MT | |
Schinus molle | Fruiting branch/photo JMR | |
Schinus molle | Tree branches/photo JMR | |
Schinus molle | Leaves/photo BAR | |
Schinus molle | Flowering branch/photo BAR | |
Schinus molle | Floral close-up/photo BAR | |
Schinus molle | Fruit/photo BAR | |
Schinus polygamus | Branches/photo BAR | |
Schinus polygamus | Leaves/photo BAR | |
Schinus polygamus | Nasty apical spine/photo BAR | |
Schinus polygamus | Bolting suckers/photo BAR | |
Schinus polygamus | Bark/photo BAR | |
Schinus terebinthifolius | Flowering branch/photo JMR | |
Schinus terebinthifolius | Fruiting branch/photo JMR | |
Schinus terebinthifolius | Fruit/photo JMR | |
Schinus terebinthifolius | Sterile understory/photo JMR | |
Schinus terebinthifolius | Young leaves/photo BAR | |
Schinus terebinthifolius | Old fruit I/photo BAR | |
Schinus terebinthifolius | Old fruit II/photo BAR | |
Schinus terebinthifolius | Shaded leaves/photo BAR | |
Schinus terebinthifolius | Sunny leaves/photo BAR | |
Schismus spp. | On desert floor I/photo JMR | |
Schismus spp. | On desert floor II/photo JMR | |
Schismus spp. | On desert floor III/photo JMR | |
Senecio jacobaea | Flowering plant/photo MT | |
Senecio jacobaea | Foreground weeds/photo JMR | |
Sesbania exaltata | Branchlet/photo BAR | |
Sesbania punicea | Small tree/photo JMR | |
Sesbania punicea | Flowering branch/photo JMR | |
Sesbania punicea | Flowers/photo JMR | |
Sesbania punicea | Fruit/photo BAR | |
Sesbania punicea | Fruiting tree/photo BAR | |
Sesbania punicea | Infested island/photo BAR | |
Silybum marianum | Prickly plants/photo JMR | |
Silybum marianum | Spiny flowers I/photo JMR | |
Silybum marianum | Spiny flowers II/photo JMR | |
Silybum marianum | A world of pain/photo JMR | |
Silybum marianum | Pretty leaves I/photo BAR | |
Silybum marianum | Pretty leaves II/photo BAR | |
Sinapis arvensis | Fruit/photo JMR | |
Sisymbrium orientale | A grassland invasion/photo JMR | |
Sisymbrium orientale | Dominating grassland along the road/photo JMR | |
Sisymbrium orientale | S. orientale patch with billy goat skull/photo JMR | |
Solanum dulcamara | Flowers and leaves/photo JMR | |
Solanum viarum | Bushes/photo Randy Westbrooks(*) | |
Solanum viarum | More bushes/photo JMR | |
Sonchus arvensis | Flowering plants/photo JMR | |
Sorghum halepense | Plant portrait/photo BAR | |
Sorghum halepense | A flowering stem/photo BAR | |
Sorghum halepense | Branches/photo BAR | |
Sorghum halepense | Awns on florets/photo BAR | |
Sorghum halepense | Bad!/photo JMR | |
Sorghum halepense | Ratty plants/photo JMR | |
Sparaxis bulbifera | White flowered plant/photo JMR | |
Spartina alterniflora | Mudflat I/photo JMR | |
Spartina alterniflora | Mudflat II/photo JMR | |
Spartina alterniflora | Dense plants/photo JMR | |
Spartium junceum | More flowers/photo JMR | |
Spartium junceum | Flowering bushes/photo JMR | |
Spartium junceum | Young fruit/photo JMR | |
Spartium junceum | More invading bushes/photo JMR | |
Spartium junceum | Flowering bush/photo JMR | |
Spartium junceum | Big plants/photo BAR | |
Spartium junceum | Needle-branches/photo BAR | |
Spartium junceum | Branches close up/photo BAR | |
Spartium junceum | Single bush/photo JMR | |
Spartium junceum | Flowers close-up/photo JMR | |
Spathodea campanulata | Branches/photo JMR | |
Spathodea campanulata | Flowers/photo JMR | |
Spathodea campanulata | More flowers/photo JMR | |
Spathodea campanulata | Yellow flowers/photo JMR | |
Sphaerophysa salsula | Seedlings/photo MT | |
Sphaerophysa salsula | Dead grey growth/photo MT | |
Sphaerophysa salsula | Big grey patch/photo MT | |
Taeniatherum caput-medusae | Close-up of seed head/photo JMR | |
Taeniatherum caput-medusae | Big awns/photo BAR | |
Taeniatherum caput-medusae | In the field/photo JMR | |
Taeniatherum caput-medusae | Matted plants/photo JMR | |
Tamarix aphylla | Tree/photo JMR | |
Tamarix aphylla | Flowers I/photo JMR | |
Tamarix aphylla | Flowers II/photo JMR | |
Tamarix aphylla | Leaves/photo JMR | |
Tamarix parviflora | Flower detail I/photo BAR | |
Tamarix parviflora | Flower detail II/photo BAR | |
Tamarix parviflora | Many flowers/photo JMR | |
Tamarix parviflora | Streamside I/photo JMR | |
Tamarix parviflora | Streamside II/photo JMR | |
Tamarix parviflora | Streamside III/photo JMR | |
Tamarix parviflora | In streambed I/photo JMR | |
Tamarix parviflora | In streambed II/photo JMR | |
Tamarix ramosissima | Colorado River/photo JMR | |
Tamarix ramosissima | In Grand Canyon I/photo JMR | |
Tamarix ramosissima | In Grand Canyon II/photo JMR | |
Tamarix ramosissima | Flowers/photo JMR | |
Tamarix ramosissima | Shrubby trees/photo JMR | |
Tamarix ramosissima | Single bush/photo JMR | |
Tamarix ramosissima | Scraggly plants/photo JMR | |
Tamarix sp. | A bushy plant/photo JMR | |
Tamarix sp. | In flower/photo JMR | |
Tamarix sp. | Flower clusters/photo JMR | |
Tamarix sp. | Fall colors I/photo JMR | |
Tamarix sp. | Fall colors II/photo JMR | |
Tamarix sp. | Dense growth/photo JMR | |
Tamarix sp. | In a river/photo JMR | |
Tibouchina herbacea | A thick marsh/photo Pat Bily(*) | |
Tibouchina herbacea | Many plants!/photo Pat Bily(*) | |
Tibouchina urvilleana | Trees/photo JMR | |
Tibouchina urvilleana | Flowers/photo JMR | |
Tithonia diversifolia | Flowers/photo JMR | |
Toona ciliata | Trees/photo JMR | |
Toona sinensis | Looking up I/photo JMR | |
Toona sinensis | Looking up II/photo JMR | |
Tragopogon dubius | Inflorescence/photo JMR | |
Tragopogon dubius | Plants/photo JMR | |
Tragopogon porrifolius | Seed head/photo JMR | |
Tragopogon sp. | Flower, WY/photo JMR | |
Tragopogon sp. | Seed head, MT/photo JMR | |
Trapa natans | Lake weeds/photo JMR | |
Trapa natans | Lots a' weeds/photo JMR | |
Trapa natans | Where did the lake go?/photo JMR | |
Trapa natans | On the water's edge/photo JMR | |
Tribolium obliterum | Along a rock/photo Susan Hubbard(*) | |
Tribolium obliterum | On the ground/photo Susan Hubbard(*) | |
Tribolium obliterum | Clusters/photo Susan Hubbard(*) | |
Tribolium obliterum | Stolons/photo Susan Hubbard(*) | |
Tribolium obliterum | Herbarium images/photo BAR (WYSIWYG--see note at bottom) | |
Tribolium uniolae | Inflorescence/photo JMR | |
Tribulus terrestris | Matted plants/photo JMR | |
Tribulus terrestris | Spiny fruit-ouch! ouch!/photo JMR | |
Tribulus terrestris | Sprawling stems/photo JMR | |
Tropaeolum majus | Orange flowers/photo JMR | |
Typha angustifolia | Pondside/photo MT | |
Typha angustifolia | Tall glade/photo MT | |
Typha angustifolia | In flower/photo MT | |
Typha angustifolia | A whole field/photo MT | |
Typha latifolia | A thick growth/photo BAR | |
Typha latifolia | Cattails!/photo BAR | |
Ulex europaeus | A bush and human head/photo JMR | |
Ulex europaeus | Flowering branch/photo JMR | |
Ulex europaeus | Pokey branches/photo JMR | |
Ulex europaeus | Flowers/photo JMR | |
Ulex europaeus | Spiny pathway/photo JMR | |
Ulex europaeus | Pokey flowers/photo JMR | |
Ulex europaeus | Juvenile plants/photo JMR | |
Ulmus pumila | Tree/photo JMR | |
Ulmus pumila | Leaves and bark/photo JMR | |
Ulmus pumila | Leaves/photo JMR | |
Ulmus pumila | Seedling/photo JMR | |
Ulmus pumila | Young tree/photo JMR | |
Urochloa decumbens | Flowers/photo JMR | |
Utricularia inflata | Emergent inflorescences/photo BAR | |
Utricularia inflata | Flowers/photo BAR | |
Utricularia inflata | Many bladders/photo BAR | |
Utricularia inflata | Bladder--top view/photo BAR | |
Utricularia inflata | Bladder--side side/photo BAR | |
Ventenata dubia | Plant features/photo BAR (WYSIWYG--see note at bottom) | |
Ventenata dubia | Infestation/photo JMR | |
Verbascum blattaria | White flower/photo JMR | |
Verbascum blattaria | Yellow flower/photo JMR | |
Verbascum thapsus | Large flowering plants/photo JMR | |
Verbascum thapsus | A first-year rosette/photo JMR | |
Verbascum thapsus | Close-up of flowers/photo JMR | |
Verbascum thapsus | A blight on a beautiful view/photo JMR | |
Verbascum thapsus | Island invasion/photo JMR | |
Verbascum thapsus | Wi/weed scientist's children/photo JMR | |
Verbascum thapsus | Flower close-up/photo JMR | |
Verbascum thapsus | Dominican Republic rosette/photo JMR | |
Verbascum thapsus | Dominican Republic sunny invasion/photo JMR | |
Verbascum virgatum | Flowers/photo JMR | |
Verbena bonariensis | Plants/photo JMR | |
Verbena bonariensis | One plant/photo BAR | |
Vinca major | Flowers/photo BAR | |
Vinca major | Leafy nasties/photo BAR | |
Vinca major and weed geek | Flowers/photo JMR | |
Vinca major/V. minor | Flower comparison/photo BAR | |
Vinca minor | Flowers/photo JMR | |
Vincetoxicum nigrum | Seedling/photo Charlotte Pyle (USDA) (*) | |
Vincetoxicum nigrum | Leaves/photo Charlotte Pyle (USDA) (*) | |
Vincetoxicum nigrum | Flowers/photo Charlotte Pyle (USDA) (*) | |
Vincetoxicum nigrum | Fruit/photo Charlotte Pyle (USDA) (*) | |
Vincetoxicum nigrum | Understory infestation/photo JMR | |
Watsonia bulbillifera | Flowers/photo JMR | |
Watsonia bulbillifera | Floral close-up/photo JMR | |
Watsonia bulbillifera | Bulbils galore/photo JMR | |
Watsonia bulbillifera | More flowers/photo JMR | |
Watsonia bulbillifera | Big infestation/photo JMR | |
Wisteria floribunda | Autumn leaves/photo BAR | |
Wisteria sinensis | Fruiting pods/photo BAR | |
Wisteria sinensis | Pods in space!/photo BAR | |
Wisteria sinensis | Pods close up/photo BAR | |
Wisteria sinensis | Seeds/photo BAR | |
Wisteria sinensis | Leaves/photo BAR | |
Wisteria sinensis | Shocked ecologist/photo BAR | |
Wisteria sinensis | Strangling stem/photo BAR | |
Xanthium spinosum | Painful plants/photo BAR | |
Xanthium spinosum | Spiny branch/photo JMR | |
Xanthium spinosum | Veined leaves/photo JMR | |
Xanthium strumarium | Dreary plants/photo JMR | |
Xanthium strumarium | Spiny cockleburs/photo JMR | |
Xanthium strumarium | Fruiting branch/photo JMR | |
Xanthium strumarium | Fruiting plant/photo JMR | |
Zantedeschia aethiopica | Lily/photo JMR | |
Zantedeschia aethiopica | Many lilies/photo JMR | |
Zantedeschia aethiopica | Lot's o' lilies/photo JMR | |
Zantedeschia aethiopica | Shady lilies/photo JMR | |
Zantedeschia aethiopica | Lookin' at lilies/photo JMR | |
Zantedeschia aethiopica | Midrange cluster/photo JMR | |
Zantedeschia aethiopica | Pretty invasion/photo JMR | |
Zantedeschia aethiopica | By a wetland/photo JMR | |
Zantedeschia aethiopica | Flower in NZ/photo JMR |
See the next set of photos
(*)Image rights are not available for this image through The Nature Conservancy. Contact the image owner for image use guidelines.
WYSIWYG--Higher resolution images are not available for this file.
(*)Image rights are not available for this image through The Nature Conservancy. Contact the image owner for image use guidelines.
WYSIWYG--Higher resolution images are not available for this file.
Other site resources
Invasive plant management
Research the information we have on the management of a particular species of invasive plant here.
Research the information we have on the management of a particular species of invasive plant here.
Invasive animal & pathogen management
Research the information we have on the management of a particular species of invasive animal or pathogen here.
Research the information we have on the management of a particular species of invasive animal or pathogen here.
Gallery of pests
A rogue's gallery of many of the invasive pests and pathogens that have invaded North America, or that have the potential to do so.
A rogue's gallery of many of the invasive pests and pathogens that have invaded North America, or that have the potential to do so.