"Invasive" plants are non-native species that have spread into native or minimally managed plant systems in Massachusetts. These plants cause economic or environmental harm by developing self-sustaining populations and becoming dominant and/or disruptive to those systems. As defined here, "species" includes all synonyms, subspecies, varieties, forms, and cultivars of that species unless proven otherwise by a process of scientific evaluation.

Acer platanoides L. (Norway maple)

A tree occurring in all regions of the state in upland and wetland habitats, and especially common in woodlands with colluvial soils. It grows in full sun to full shade. Escapes from cultivation; can form dense stands; out-competes native vegetation, including sugar maple; dispersed by water, wind and vehicles.

Acer pseudoplatanus L. (Sycamore maple)

A tree occurring mostly in southeastern counties of Massachusetts, primarily in woodlands and especially near the coast. It grows in full sun to partial shade. Escapes from cultivation inland as well as along the coast; salt-spray tolerant; dispersed by wind, water and vehicles.

Aegopodium podagraria L. (Bishop’s goutweed; bishop’s weed; goutweed)

A perennial herb occurring in all regions of the state in uplands and wetlands. Grows in full sun to full shade. Escapes from cultivation; spreads aggressively by roots; forms dense colonies in flood plains.

Ailanthus altissima (P. Miller) Swingle (Tree-of-heaven)

This tree occurs in all regions of the state in upland, wetland, & coastal habitats. Grows in full sun to full shade. Spreads aggressively from root suckers, especially in disturbed areas.

Alliaria petiolata (Bieb.) Cavara & Grande (Garlic mustard)

Synonym: Alliaria officinalis Andrz. Ex Bieb.

A biennial herb occuring in all regions of the state in uplands. Grows in full sun to full shade. Spreads aggressively by seed, especially in wooded areas.

Alnus glutinosa (L.) Gaertner (Black alder, European alder)

A rapidly growing tree, native to Europe and portions of northern Africa and Asia, that has been widely planted for ornamental purposes and for erosion control. Black alder is primarily a riparian species that forms large stands and readily disperses via waterways, wildlife and wind. It may hybridize with other alder species.

Berberis thunbergii DC. (Japanese barberry)

A shrub occuring in all regions of the state in open and wooded uplands and wetlands. Grows in full sun to full shade. Escaping from cultivation; spread by birds; forms dense stands.

Cabomba caroliniana A.Gray (Carolina fanwort; fanwort)

A perennial herb occuring in all regions of the state in aquatic habitats. Common in the aquarium trade; chokes waterways.

 

Celastrus orbiculatus Thunb. (Oriental bittersweet; Asian or Asiatic bittersweet)

A perennial vine occuring in all regions of the state in uplands. Grows in full sun to partial shade. Escaping from cultivation; berries spread by birds and humans; overwhelms and kills vegetation.

 

Cynanchum louiseae Kartesz & Gandhi (Black swallow-wort, Louise’s swallow-wort)

Synonyms: Cynanchum nigrum (L.) Pers. non Cav.; Vincetoxicum nigrum (L.) Moench

A perennial vine occurring in all regions of the state in upland, wetland, and coastal habitats. Grows in full sun to partial shade. Forms dense stands, out-competing native species: deadly to Monarch butterflies.

 

Elaeagnus umbellata Thunb. (Autumn olive)

A shrub occurring in uplands in all regions of the state. Grows in full sun. Escaping from cultivation; berries spread by birds; aggressive in open areas; has the ability to change soil.

Eragrostis curvula (Schrad.) Nees (Weeping lovegrass)

A perennial warm season bunchgrass that occurs on road edges, agricultural grasslands, sandplain grassland, and coastal heathland areas, mainly in coastal and island counties. In globally rare early successional habitats, this grass has demonstrated the ability to expand rapidly. (Reviewed 2021)

Euonymus alatus (Thunb.) Sieb. (Winged euonymus; Burning bush)

A shrub occurring in all regions of the state and capable of germinating prolifically in many different habitats. It grows in full sun to full shade. Escaping from cultivation and can form dense thickets and dominate the understory; seeds are dispersed by birds.

 

Euphorbia esula L. (Leafy spurge; wolf’s milk)

A perennial herb occurring in all regions of the state in grasslands and coastal habitats. Grows in full sun. An aggressive herbaceous perennial and a notable problem in western USA.

 

Fallopia japonica (Houtt.) Dcne. (Japanese knotweed; Japanese or Mexican Bamboo)

Synonym: Polygonum cuspidatum Sieb. & Zucc.; Reynoutria japonica Houtt.

A perennial herbaceous subshrub or shrub occurring in all regions of the state in upland, wetland, and coastal habitats. Grows in full sun to full shade, but hardier in full sun. Spreads vegetatively and by seed; forms dense thickets.

Ficaria verna Huds. (Lesser celandine; fig buttercup)

Synonyms: Ranunculus ficaria L.

A perennial herb occurring on stream banks, and in lowland and uplands woods in all regions of the state. Grows in full sun to full shade. Propagates vegetatively and by seed; forms dense stands especially in riparian woodlands; an ephemeral that outcompetes native spring wildflowers.

Frangula alnus P. Mill. (European buckthorn; glossy buckthorn)

Synonyms: Rhamnus frangula L.; R. frangula var. angustifolia Loud.

Shrub or tree occurring in all regions of the state in upland, wetland, and coastal habitats. Grows in full sun to full shade. Produces fruit throughout the growing season; grows in multiple habitats; forms thickets.

 

Glaucium flavum Crantz (Sea or horned poppy; yellow hornpoppy)

A biennial and perennial herb occurring in southeastern MA in coastal habitats. Grows in full sun. Seeds float; spreads along rocky beaches; primarily Cape Cod and Islands.

 

Hesperis matronalis L. (Dame’s rocket)

A biennial and perennial herb occurring in all regions of the state in upland and wetland habitats. Grows in full sun to full shade. Spreads by seed; can form dense stands, particularly in flood plains.

 

Iris pseudacorus L. (Yellow iris)

A perennial herb occurring in all regions of the state in wetland habitats, primarily in flood plains. Grows in full sun to partial shade. Out-competes native plant communities.

 

Lepidium latifolium L. (Broad-leaved pepperweed; tall pepperweed)

A perennial herb occurring in eastern and southeastern regions of the state in coastal habitats. Grows in full sun. Primarily coastal at upper edge of wetlands; also found in disturbed areas; salt tolerant.

 

Lonicera japonica Thunb. (Japanese honeysuckle)

A perennial vine occurring in all regions of the state in upland, wetland, and coastal habitats. Grows in full sun to full shade. Rapidly growing, dense stands climb and overwhelm native vegetation; produces many seeds that are bird dispersed; more common in southeastern Massachusetts.

 

Lonicera morrowii A.Gray (Morrow’s honeysuckle)A shrub occurring in all regions of the state in upland, wetland, and coastal habitats. Grows in full sun to full shade. Part of a confusing hybrid complex of nonnative honeysuckles commonly planted and escaping from cultivation via bird dispersal.

Lonicera x bella Zabel [morrowii x tatarica] (Bell’s honeysuckle)

This shrub occurs in all regions of the state in upland, wetland, and coastal habitats. Grows in full sun to full shade. Part of a confusing hybrid complex of nonnative honeysuckles commonly planted and escaping from cultivation via bird dispersal.

 

Lysimachia nummularia L. (Creeping jenny; moneywort)

A perennial herb occurring in all regions of the state in upland and wetland habitats. Grows in full sun to full shade. Escaping from cultivation; problematic in flood plains, forests and wetlands; forms dense mats.

 

Lythrum salicaria L. (Purple loosestrife)

A perennial herb or subshrub occurring in all regions of the state in upland and wetland habitats. Grows in full sun to partial shade. Escaping from cultivation; overtakes wetlands; high seed production and longevity.

Myriophyllum heterophyllum Michx. (Variable water-milfoil; Two-leaved water-milfoil)

A perennial herb occurring in all regions of the state in aquatic habitats. Chokes waterways, spread by humans and possibly birds.

Myriophyllum spicatum L. (Eurasian or European water-milfoil; spike water-milfoil)

A perennial herb found in all regions of the state in aquatic habitats. Chokes waterways, spread by humans and possibly birds.

Phalaris arundinacea L. (Reed canary-grass)

This perennial grass occurs in all regions of the state in wetlands and open uplands. Grows in full sun to partial shade. Can form huge colonies and overwhelm wetlands; flourishes in disturbed areas; native and introduced strains; common in agricultural settings and in forage crops.

Phragmites australis (Cav.) Trin. ex Steud. subsp. australis (Common reed)

A perennial grass (USDA lists as subshrub, shrub) found in all regions of the state. Grows in upland and wetland habitats in full sun to full shade. Overwhelms wetlands forming huge, dense stands; flourishes in disturbed areas; native and introduced strains.

Polygonum perfoliatum L. (Mile-a-minute vine or weed; Asiatic tearthumb)

Synonyms: Persicaria perfoliata (L.) H. Gross; Ampelygonum perfoliatum (L.) Roberty & Vautier

This annual herbaceous vine is currently known to exist in several counties in MA, and has also has been found in RI and CT. Habitats include streamside, fields, and road edges in full sun to partial shade. Highly aggressive; bird and human dispersed.

Potamogeton crispus L. (Crisped pondweed; curly pondweed)

A perennial herb occurring in all regions of the state in aquatic habitats. Forms dense mats in the spring and persists vegetatively.

Rhamnus cathartica L. (Common buckthorn)

A shrub or tree occurring in all regions of the state in upland and wetland habitats. Grows in full sun to full shade. Produces fruit in fall; grows in multiple habitats; forms dense thickets.

Robinia pseudoacacia L. (Black locust)

A tree that occurs in all regions of the state in upland habitats. Grows in full sun to full shade. While the species is native to central portions of Eastern North America, it is not indigenous to Massachusetts. It has been planted throughout the state since the 1700’s and is now widely naturalized. It behaves as an invasive species in areas with sandy soils.

Rosa multiflora Thunb. (Multiflora rose)

A perennial vine or shrub occurring in all regions of the state in upland, wetland and coastal habitats. Grows in full sun to full shade. Forms impenetrable thorny thickets that can overwhelm other vegetation; bird dispersed.

Salix atrocinerea/Salix cinerea L. (Large Gray Willow/Rusty Willow)

A large shrub or small tree most commonly found in the eastern and southeastern areas of the state, with new occurrences being reported further west. Primarily found on pond shores but is also known from other wetland types and rarely uplands. Salix atrocinerea L. / Salix cinerea L. are either recognized as closely related species or the conspecific subspecies Salix cinerea ssp. oleifolia and S. cinerea ssp. cinerea. Forms dense stands and can out-compete native species along the shores of coastal plain ponds. (Reviewed 2014)

Trapa natans L. (Water-chestnut)

An annual herb occurring in the western, central, and eastern regions of the state in aquatic habitats. Forms dense floating mats on water.