Invasive Species Lists

You’d think that it would be easy to make a list of the invasive species in a place a small and well traveled as Rhode Island. You’d be wrong.

There are different definitions for different uses and users to that makes counting hard. We don’t even know all the species that occur in Rhode Island and some of the unknown ones are bound to be non-native and potentially invasive. Many species we have found in Rhode Island are of unknown nativity…they’ve been here as long as we’ve been looking, but that doesn’t mean they’ve always been here. Finally, for many of the more obscure organisms, even the best scientists can’t even identify them to species.

So we have a whole page of lists. We annotate each list so you’ll know what the purpose was for its creation and what relevance it has for different user groups today.

2001 RIISC Invasive Plant List
In 2001, the RIISC agreed to a list of invasive plants in Rhode Island. The list is broken up into the following categories:
Widespread and Invasive
Restricted and Invasive
Invasive but Need More Information
Needs More Research and Monitoring/Observation
Potentially Invasive
Weedy

This list is now getting a little dated. There have been a number of important invaders found since it was written and the status of a number on the list would probably be different if it were done again. Nonetheless, there has not been as broad a stakeholder agreement about any other list since that time so it still has some value for understanding both the ecological and political situation of invasive plants in Rhode Island.
Download a copy of the 2001 invasive plant list. PDF/90KB

Forest Health Works Project (FHWP) Priority Species List
In 2010, using funds from a U.S. Forest Service grant of federal stimulus funds (the Forest Health Works Project or FHWP), RINHS produced another, more up to date invasive plant list organized by status and growth habit. It was produced with considerable input from statewide environmental scientists and managers but not the same breadth of industry and other stakeholders that came together to produce the 2001 list. This 2010 list, with some modifications and updating as of October 2013, is likely the most accurate simple assessment of invasive plant presence and status in Rhode Island.
Download a copy of the 2013 invasive plant list: Rhode Island Invasive Species_2013_b. PDF/220KB

RINHS Easy Eight and Dirty Dozen
In 2010 RINHS led a series of invasive species workshops targeted at the general public. To make attendees confident about getting involved in invasive species management we created two lists that focus on species that are not easily confused by beginners and for which there are control techniques not requiring technical skills or specialized equipment. These are The Easy Eight and The Dirty Dozen.
Get the lists, along with advice to conservation land owners on invasives management. PDF:870K

Watershed Counts Invasives Metric Assessment Basket
In 2011, RIISC began assisting the Narragansett Bay Estuary Program and URI’s Coastal Institute with a project called Watershed Counts. Watershed Counts is a collaborative effort by groups in Rhode Island to quantify environmental condition and change through time using a variety of metrics, interpreting existing scientific knowledge, and publicizing its findings in ways that inform and engage the general public. Watershed Counts is funded by grants from the Rhode Island Foundation and the U.S. Environmental Protection Agency Healthy Communities Grant Program.

RIISC’s role in Watershed Counts is to develop a metric for invasive species that incorporates both on-the ground measurements of invasives extent and impact and assessments of invasive survey and management efforts. The development process includes meetings, surveys, and other communications. Learn more on the Invasives Metric Project Page. We developed a list of nominee species, most of the species of significance either currently present in Rhode Island or present nearby, as well as a shorter list for plants, of species we would review annually to establish trends in invasive impact and management capacity.
Nominee list for terrestrial, marine, and freshwater species (includes nominee and assessment basket critiera)
Metric Assessment Basket—Terrestrial:
Does not occur in RI, but could:
zebra mussel
Chinese mitten crab
hydrilla
European frog-bit

Limited distribution
parrot feather
Eurasian water nymph
rusty crayfish
American water lotus

Moderate distribution:
Asiatic clam
water chestnut
European carp
water hyacinth

Wide distribution:
fanwort
purple loosestrife
variable milfoil
phragmites