Why invasive species are bad

Invasive species are responsible for:

Increasing the intensity, frequency, and size of wildfires
Altering soil chemistry and nutrient levels
Lowering water tables
Altering rates of sedimentation and erosion
Displacing or outcompeting native plant species
Degrading or eliminating habitat for native animals and organisms
Providing habitat for undesireable non-native animals and organisms
Posing a serious threat to native wildlife by upsetting delicate food webs

See a directory of North American pests here.