The Argentine black and white tegu is native to South American and the first established population in the U.S. was documented in Florida in 2006. It's means of introduction was via the pet trade and the Argentine black and white tegu is a generalist omnivore that preys on many native species.
Asian jumping worms are native to east-central Asia and have been present in the U.S. since the late 1800s, but have been recently invading natural habitats in the Northeast and Midwest. These worms were introduced possibly through the horticultural trade or by anglers using them as bait. Asian jumping worms affect forest habitats by altering soil properties, resulting in reduced food resources for native species.
The Asian longhorned tick is native to eastern Asia. It was first detected in New Jersey in 2017. The full public health and agricultural impact of this tick and spread is unknown. It is a potential vector of several human and animal diseases present in the U.S.
Beach leaf disease was first observed in Ohio in 2012. It's means of introduction is unknown, although it may have arrived in North America through the transport of wood with an invertebrate vector. It causes a disease of beech trees that disfigures leaves and can lead to tree mortality.
Box tree moth was confirmed in the U.S. in 2021 after it was imported on nursery plants shipped from Canada. This moth feeds primarily on boxwood plants (Buxus spp.), where heavy infestations can defoliate plants and lead to plant death.
Boxwood blight was first discovered in the United Kingdom in 1994; its origin is unknown. Boxwood blight was detected in the U.S. in 2011 and the means of introduction is unknown. It is a fungal disease of boxwood plants, which are widely used as landscape ornamentals.
Brown spruce beetle is native to Central Europe and Asia. It has not yet been introduced to the United States but has been established in Nova Scotia, Canada since 1990. It can be spread through the movement of infested wood products. This invasive beetle colonizes and attacks healthy spruce trees.
The callery pear (bradford pear) is native is East Asia and was imported to the U.S. in 1908 and first sold commercially in 1961. Callery pear trees forms dense thorny thickets, produces flowers with an offensive odor, and produces large amounts of fruit that litter sidewalks. Additionally, the ‘Bradford’ cultivar is extremely susceptible to damage from storms due to branches having narrow crotch angles; these trees will also split under their own weight after 15-20 years of growth.
Citrus black spot was first discovered in Australia and was introduced to the U.S. in 2010. The means of introduction was possibly through the importation of unregulated and/or non-commercial infected fruit. Citrus black spot is a fungal disease of citrus that decreases yields by causing external blemished and premature fruit drop.
English ivy is native to Europe and was introduced to the U.S. via the nursery trade. The earliest records of naturalization are from the 1870s. English ivy competes with native plants and can spread into tree canopies.
The Gambian giant pouched rat is native to African. It was discovered in Florida in 2004, but was first introduced in 1999. The rat was released by an exotic pet breeder. This species is a large rodent capable of becoming highly destructive to agricultural crops and native species and may also serve as a vector of several diseases.
Golden nematode was first discovered in Long Island, New York in 1941. It was possibly transported on military equipment returning from Europe after World War I. If left uncontrolled, the golden nematode is capable of causing a 100% loss in potato yields.
Hammerhead worm was first discovered in 1891. It was introduced by movement of infested plants and soil. These worms are predators of earthworms, could potentially impact agricultural, horticultural, and natural ecosystems
The Japanese beetle is native to Japan. It was first discovered in 1916 but was probably introduced around 1911. It was introduced possibly in the soil of imported ornamental plants. This beetle is a destructive pest of turf, landscape plants, and crops; adults feed on the foliage and fruits of several hundred species of trees, shrubs, vines, and crops, while larvae feed on the roots of grasses and other plants.
The New Guinea flatworm was first found in Florida in 2012. It's method of introduction is unknown, although land flatworms have been known to be introduced in the soil of imported plants. New Guinea flatworms are predators of land snails.
The northern giant hornet is native to Asia and was first detected in Washington State in 2019. It possibly was introduced through the illegal importation of live specimens for food and medicinal purposes. This hornet is a pest of honey bees that can cause the complete loss of colonies.
Oak wilt is a fungal disease of oaks that can rapidly kill susceptible species (particularly red oaks). The origin and means of the introduction of oak wilt are unknown. The disease was first discovered in 1942 and is currently only found in the U.S., but it may have originated in Mexico, Central America, or South America.
The pale cyst nematode is native to South America. It was first discovered in Idaho in 2006. It is a major pest of potatoes and related crops. Uncontrolled infestations can reduce crop yields by 80%.
Palmer amaranth is native to Southwestern U.S. and was first reported outside of its native range in Virginia in 1915, but was not a significant weed in the Southeast until the 1990s. This species is one of the most economically important weeds of corn, cotton, and soybean; some populations are resistant to glyphosate and other herbicides.
Red-bellied pacu is native to South America. Individual specimens have been caught since the 1960s, but no reproducing populations have yet become established in the U.S. This species was probably introduced through aquarium releases or fish farm escapes. The environmental impact is unknown.