Invasive species are a serious worldwide threat to natural resources. Presidential Executive Order 13112 defines an invasive species as “an alien species whose introduction does or is likely to cause economic or environmental harm or harm to human health.” Executive Order 13112 requires Federal agencies to prevent and control these species and to minimize their economic, ecological, and human health impacts. Environmental and economic costs caused by invasive species in the U.S. alone were estimated by Pimentel et al. (2005) to exceed $120 billion per year.1
Invasive species threatening Region 3 range from disease pathogens to mammals (see list of invasive species by national forest). Specific information on invasive species affecting national forests and grasslands in Region 3 may be found by accessing the information blocks below.
Invasive plants have been introduced into the Southwest from different countries or other parts of the U.S. Although many non-native plants are relatively harmless in their new environment or are even beneficial to society, invasive plants can spread rapidly and threaten native ecosystems.
There are a number of invasive weeds currently affecting wilderness areas in the Southwest. Controlling these weedy species requires implementation of specific processes that are in compliance with the Wilderness Act of 1964.