Determining Invasiveness

IPSAWG Species Assessments

The Indiana Department of Natural Resources brought together numerous agencies and organizations to assess which plant species threaten natural areas in Indiana and to develop recommendations regarding the use of specific plant species. The Invasive Plant Species Assessment Work Group (IPSAWG)  compiled detailed information on those species regarded as invasive.

For each species, IPSAWG assessed invasion status (where found and how extensive) and assigned point values to its ecological impacts, potential for expansion, difficulty of management, and commercial value. From this they developed detailed recommendations—for example, developing policies against selling the species, providing education on why not to use it, or removing it from city planting lists, etc.

IPSAWG’s excellent Fact Sheets present four-color photos of each species, a description, plant origin, invasiveness rating, recommendations, and native plants that can be planted as alternatives.   

View IPSAWG Species Assessments

IDNR Invasive Species Home

Read “Invasive Horticultural Plants in Indiana: Some Answers,” an article by Ellen Jacquart, published in the Indiana Nursery & Landscape Association journal, about how the IPSAWG list is being used.  View the article

Indiana Invasive Species Council

The Indiana Invasive Species Council (IISC) was established in 2009 by the state legislature to enhance the ability of government agencies to detect, prevent, monitor, and manage new and long-established invasions, as well as increase public awareness about these growing threats.

The Council’s most important function is to give citizens and industries a way to voice concerns and opinions about the management of invasive species in Indiana while providing science-based, relevant information about current or emerging issues. To this end, they will conduct a public informational meeting every two years. 

Invasive Plant Advisory Committee

Created by Indiana’s Invasive Species Council, IPAC is creating a science-based, transparent invasive plant list for Indiana and is developing best management practices for government agencies’ response to invasives.

Ellen Jacquart is leading the invasive plant list project, and has outlined different processes according to four categories of plants: (1) obligate wetland species that have already been assessed through Doug Keller’s Aquatic Invasive Advisory Committee (4 species); (2) plant species previously assessed through the Invasive Plant Species Assessment Working Group (32 species); (3) plants in trade that have not yet been assessed through the IPSAWG process (22 species); and (4) plants not in trade that have not yet been assessed through the IPSAWG process (38 species).

Tom Tremain is leading the best management practices effort, possibly simplifying a template developed in Wisconsin. A draft will be shared with relevant agencies to help refine the BMPs.

Cooperative Agricultural Pest Survey (CAPS)

The Survey’s  “Most Unwanted” Invasive Plant Pest List  identifies invasive plant pests (bugs) regulated by state or federal laws and the distribution of pests that may threaten the state’s plant resources, whether cultivated or natural plant communities. Updated yearly, the list helps determine how resources for surveys, outreach, and educational programs are best spent to protect Indiana.