Invasive Plants

In general, invasive plants have the following characteristics:

• They are alien (non-native) plant.
• They grow and spread rapidly over large areas.
• They are free from natural controls, including herbivores, parasites, and diseases.

See Identify Plants for information about the invasive plants in the IFCWMA
See Field Guides for tools to identify weeds in the field

Impact of invasive plants

Invasive non-native organisms are one of the greatest threats to the natural ecosystems of the U.S. and are destroying America's natural history and identity.

Approximately 4,000 species of exotic plants (Kartesz and Morse 1997) and 500 exotic animals (Office of Technology Assessment 1993) have established free-living populations in the United States. Nearly seven hundred are known to cause severe harm to agriculture at a cost of billions of dollars annually.

The known ecological impacts of invasive plants include: 

• Reduce biodiversity
• Endanger and threaten species and their habitat
• Reduce habitat for native insects, birds, and other wildlife 
• Decrease food sources for wildlife
• Change natural ecological processes, such as plant community succession 
• Alter the frequency and intensity of natural fires 
• Disrupt native plant-animal associations, such as pollination, seed dispersal, and host-plant relationships

Source: Alien Plant Invaders of Natural Area http://www.nps.gov/plants/alien/bkgd.htm