Invasive Species & Resources

What is an invasive species?

An invasive species is a non-native species (including seeds, eggs, spores, or other propagules) whose introduction causes or is likely to cause economic harm, environmental harm, or harm to human health. The term "invasive" is used for the most aggressive species. These species grow and reproduce rapidly, causing major disturbance to the areas in which they are present.

Invasive insects in Connecticut

Spotted Lanternfly

Spotted Lanternfly

Emerald Ash Borer

Emerald Ash Borer-Adult

Asian Longhorned Beetle


Spongy Moth


Common invasive plants in Greenwich

Mile-a-Minute vine


Japanese honeysuckle




Garlic mustard


English ivy


Japanese barberry


Tree of heaven


Porcelain berry


Burning bush


Purple loosestrife


Common Reed (Phragmites)


Oriental Bittersweet


Invasive invertebrates in Connecticut

Mitten Crabs

Mitten Crabs

Jumping Worm

Jumping worms_CAES

Asian Clam

Asian Clam_CT

Zebra Mussel

Zebra Mussel_CT

If you encounter any of these invasive species, please report them here

Things to know about invasive species: 

  • Invasive species, if left uncontrolled, can and will limit land use now and into the future.
  • The longer we ignore the problem the harder and more expensive the battle for control will become.
  • Invasive species can decrease your ability to enjoy hunting, fishing, camping, hiking, boating and other outdoor recreational activities.
  • The United States suffers from $120 billion per year in economic losses due to exotic, invasive species.
  • Approximately 42% of Threatened or Endangered species are at risk due to non-native, invasive species.

University of Connecticut, UConn, has a working group and website dedicated to CT invasive plant species, called the CT Invasive Plant Working Group. Their website has a myriad of resources and information available, which includes:

SLF Graphic
SLF Graphic 2

Spotted Lanternfly Quarantine in Connecticut

Spotted Lanterfly Life Stages

The Connecticut Agricultural Experiment Station (CAES) has issued a Quarantine Order with defined restricted areas for the exotic pest spotted lanternfly, Lycorma delicatula. This insect has been detected in Connecticut with established populations detected in Fairfield and New Haven Counties and single individuals intercepted in numerous towns. The spotted lanternfly is a new plant pest to the United States and represents a threat to Connecticut’s environment, residential areas, and agricultural interests, particularly forests, orchards, vineyards, and nurseries. The purpose of this quarantine is to slow the spread of SLF within the state and provide for certification of Connecticut businesses for movement of regulated articles out of state and help protect the economic interests of the state’s agricultural industries by suppressing, controlling or eradicating infestations of spotted lanternfly in regulated areas.

Spotted Lantenfly in Greenwich

Have You Spotted This Invader?

Notice Of Order Of Quarantine

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