Invasive Species Overview

Knapweed Invasive species are one of the most serious challenges that affect natural resources worldwide.  Recent estimates of environmental and economic costs of invasive species in the United States alone approach $120 billion per year (Pimentel, Zuniga, and Morrison 2005).

President Clinton signed the Invasive Species Executive Order (E.O. 13112) in 1999 to “to prevent the introduction of invasive species and provide for their control and to minimize the economic, ecological, and human health impacts that invasive species cause.”  The E.O. further 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.”

Invasive Species Helpful Links and Documents:

Invasive Plants

Monoculture of yellow starthistle near Medford, Oregon Invasive plants have been introduced to the region or U.S. from a different region or country.  While many non-native plants are extremely beneficial to society, invasive plants spread rapidly and cause, or are likely to cause, harm to native ecosystems. Find invasive plant information here.

Invasive Animals

Feral PigsInvasive animals can have devastating effects on native vegetation, wildlife, and fish. Find information about invasive animals here.

Invasive Aquatic Species

Quagga musselAquatic invasive plants, fish, and other invasive aquatic organisms can displace and compromise native species in public waterways. Find information about aquatic invasives here.

Invasive Diseases affecting Wildlife and Fish

Bat with White NoseFind information about invasive diseases here.

Invasive Insects and Diseases Affecting Forest Health

Green alder sawfly adult; photo by Andrei Karankou, 2010Find information about forest insects and diseases and Forest Health Protection here.