Decision Support Tools

Covers risk assessments, ranking systems, and other decision-making tools for invasive plant species. See Manager's Tool Kit - Decision Support Tools for general resources and other species.

A Risk Assessment to Prevent Introduction of Pest Plant Species in Mediterranean Europe (Jun 10, 2010)
Environmental News Network.
A recent study follows the needs of the mentioned legislative acts validating the effectiveness of a Weed Risk Assessment adapted for Mediterranean Europe. Many countries in the world have already adopted a WRA with the purpose of identifying high-risk species, thereby allowing decision-making on prevention and eradication so as to avoid ecological and economic harm.

Alien Plants Ranking System Version 5.1
DOI. Northern Prairie Wildlife Research Center.
Developed in partnership with the National Park Service, Ripon College, University of Minnesota, and the U.S. Geological Survey. Designed primarily for grassland and prairie parks in the central United States, the tool helps managers to target management efforts on the most problematic species. The tool can assess potential threats and feasibility of control.

Weed-Initiated Pest Risk Assessment Guidelines for Qualitative Assessments (Aug 2004; PDF | 772 KB)
USDA. APHIS. Plant Protection and Quarantine.

Environmental Assessment – Eurasian Watermilfoil / Curlyleaf Pondweed Research Project: Sanders County (May 2009; PDF | 534 KB)
Montana Department of Agriculture.
Currently, the only known infestation of eurasian watermilfoil (Myriophyllum spicatum) in Montana is in Noxon Rapids and Cabinet Gorge Reservoirs where the plant was first discovered in 2007. Spread of this plant has the potential to impact aquatic environments and impair recreational resources.

Environmental Assessments and Documents
USDA. APHIS. Plant Protection and Quarantine.

Guidelines for Coordinated Management of Noxious Weeds: Development of Weed Management Areas
Montana State University. Center for Invasive Plant Management.
Cooperative effort between Bureau of Land Management, Forest Service, National Park Service, Montana Department of Agriculture, Idaho Department of Agriculture, Park County, Wyoming Weed & Pest Countrol District and Ag West Communications

Handbook for Ranking Exotic Plants for Management & Control (July 1993)
DOI. National Park Service.
The National Park Service has developed this ranking system to provide resource managers with a tool to sort exotic plants within a park according to the species level of impact and its innate ability to become a pest. This information can then be weighed against the perceived feasibility or ease of control. The Exotic Species Ranking System is designed to first separate the innocuous species from the disruptive species. The separation allows researchers to then concentrate further efforts on species in the disruptive category. The system is also designed to identify those species that are not presently a serious threat but have the potential to become a threat and, thus, should be monitored closely. Finally, the system asks the park manager and the ecologist to consider the cost of delaying any action.  This handbook describes the rationale of the ranking system and its components and how to adapt the system to different situations and different areas of the country.

Hawaii-Pacific Weed Risk Assessment (HPWRA) - Revised Version
Hawaiian Ecosystems at Risk Project.
The HPWRA system provides information about the invasive potential of a number of plants for Hawaii and and other Pacific islands. Revised version includes more species assessment as well as updated assessments, with permanent URLs.

Weed Risk Assessments for Hawaii and Pacific Islands - Original Version
University of Hawai'i - Manoa. Botany Department.

IFAS Assessment of the Status of Non-native Plants in Florida's Natural Areas
University of Florida. Institute of Food and Agricultural Sciences.

Invasive Exotic Plant Management Tutorial for Natural Lands Managers
Pennsylvania Department of Conservation and Natural Resources.
Prepared by: Mid-Atlantic Exotic Pest Plant Council, Inc.
A "one-stop-shop" for natural resource managers who are interested in organizing on-the-ground efforts to prevent, manage and control invasive exotic plants.

Invasive Species (I-Rank) Assessments
NatureServe Explorer.
Includes assessments for a total 452 non-native plants of the U.S., searchable by name, location, invasive impact rank (I-Rank), or a combination of these criteria. The assessments are the result of applying a systematic protocol (Morse et al. 2004) to determine the degree of impact an individual non-native species has on the native plants, animals, and ecosystems of the United States.
Note: The invasive species ranks (I-Ranks) are on the Status tab. Use the link at the top of the Status tab that says "U.S. Invasive Species Impact Rank (I-RANK)" or just scroll down the page until you see the I-Rank select criteria. You can search for individual species by name, by location or search by the overall invasive impact rank.

Invasive Weed Impact Calculator / ARS Press Release: Eliminating Weeds Could Put More Cows on the Pasture (Apr 28, 2010)
USDA. Agricultural Research Service; Montana State University Extension.
This site helps land managers decide which approach is best for their situation when battling leafy spurge or spotted knapweed. It accepts location-specific weed abundance data from land managers and uses these data to estimate weed impacts. The weed impact estimates help managers decide whether or not to use costly weed control measures to battle leafy spurge/spotted knapweed.

Invasiveness Ranking System for Non-Native Plants of Alaska (Aug 2008; 5.9 MB)
USDA. FS. Alaska Region.
R10-TP-143.

International Weed Risk Assessment Workshop
Hawaiian Ecosystems at Risk (HEAR) Project.
Disseminates information generated from workshop sessions; includes proceedings, papers, and other information resources.

Non-Native Plant Species Invasiveness Assessment
Cornell University. Cooperative Extension. New York Invasive Species Clearinghouse.
A system/protocol designed to assess the invasive nature of non-native plant species was developed by The Nature Conservancy (TNC) in New York and the Brooklyn Botanic Garden (BBG) in 2008.

Pacific Northwest Region Invasive Plant Program - Preventing and Managing Invasive Plants Final Environmental Impact Statement (Apr 2005; PDF | 2 MB)
USDA. FS. Pacific Northwest Region.

Prioritizing Weed Threats Resources
Montana State University. Center for Invasive Plant Management.

Plant Health Environmental Assessments
USDA. APHIS. Plant Protection and Quarantine.
Provides plant protection and quarantine environmental documents for various species.

Plant Species That Threaten Ecosystems of the Pacific Islands (PIER)
Pacific Island Ecosystems at Risk.
The U.S. Forest Service is pleased to announce the release of version 5.1 of the Pacific Island Ecosystems at Risk (PIER) web site and CD (Nov 2006). Over 5000 herbarium records from the Bishop Museum have been added to the location data. PIER now contains profiles of 1270 plant species, over 3000 photos and images, and over 600 risk assessments to aid in identifying and evaluating invasive plant species of concern to the Pacific region.

Plant Stewardship Index (PSI)
Bowman's Hill Wildflower Preserve (Pennsylvania).
The Plant Stewardship Index (PSI) is an analytical tool for land conservationists, land managers and property owners. The Index is designed to assist in answering two questions: What is the naturalness of any site? How have land management practices (or their absence) affected that naturalness over time?

Ranking Invasive Exotic Plant Species in Virginia (Jun 2001; PDF | 2.5 MB)
Virginia Department of Conservation and Recreation. Natural Hertiage.
Natural Heritage Technical Report 01-13

Review of the National (Australia) Weed Risk Assessment System (Nov 30, 2005; PDF | 553 KB)
Weeds Australia.
Conducted by the NWRAS Review Group - A Joint Natural Resource Management Standing Committee-Primary Industries Standing Committee Subcommittee (Approved Aug 2, 2006)

Risk Assessment for Invasive Plant Species
Weed Science Society of America.
Weed Technology: Vol. 18, No. 5, pp. 1305-1308.
Note: Abstract; full article requires subscription

Risk Assessment System for Screening out Invasive Pest Plants from Hawai'i and Other Pacific Islands
University of Hawai'i - Manoa.

Weed Control Methods Handbook: Tools and Techniques for Use in Natural Areas (Apr 4, 2001) and Templates and Planning Examples
Invasive.org.
Archive from the Nature Conservancy, Global Invasive Species Team. By Mandy Tu, Callie Hurd, & John M. Randall.

Weed Information Management System (WIMS 3)
iMapInvasives.
An application tool created by the Nature Conservancy, Global Invasive Species Team.
Weed Information Management System (WIMS 3) is a Microsoft Access-based relational database application that is designed to assist natural resource managers in managing their weed data.

Weed Risk Assessments - Noxious Weed Program (scroll to view)
USDA. APHIS. Plant Protection and Quarantine.

Weed Risk Assessments for Florida for The Nature Conservancy (Mar 3, 2010)
Hawaiian Ecosystems at Risk Project.
Weed risk assessments for Florida based on the Australia/New Zealand Weed Risk Assessment model were created for The Nature Conservancy by Doria Gordon et al. for 260 species.