An invasive species is any species that is not native to the area, and whose introduction causes, or is likely to cause, economic or environmental harm. Often, the term refers to those species that, if introduced to a site, are likely to spread and displace native plants or animals.
 
 
Recommended Resources
Center for Invasive Species and Ecosystem Health
The chief objective for this site is to provide an accessible archive of high quality images relating to invasive and exotic species, with an emphasis on its use in the educational environment. Additional features are available to registered users of the site.
http://www.invasive.org/
The Center for Safety and Environment (CSEM) is an organization that provides quality training in environmental safety. You can browse through the Center's course offerings and buy books here. The website also offers some online training opportunities.
http://csem.com/
Invasive Species Specialist Group
The ISSG was established with the goal of reducing the threat to natural ecosystems and native species by increasing awareness of the problems of invasive species, and of the ways in which they can be prevented, controlled or eradicated. A variety of informational topics related to invasive species are presented here.
http://www.issg.org/
National Invasive Species Information Center
NISIC was established at the National Agricultural Library to create and manage this site, which serves as a reference portal to information, organizations, and services on the subject of invasive species. An overview of the center is presented, including news, events, and contact data.
http://www.invasivespeciesinfo.gov/