Why Are Invasive Species a Problem?

Millions of acres of once healthy, productive rangelands, forestlands and riparian areas have been overrun by noxious or invasive weeds. They are invading recreation areas, BLM-managed public lands, National Parks, State Parks, roadsides, streambanks, Federal, state, and private lands.

Invasive weeds:

• destroy wildlife habitat

• reduce opportunities for hunting, fishing, camping and other recreational activities

• displace many Threatened and Endangered Species

• reduce plant and animal diversity because weed monocultures (areas dominated by a single plant species) over run all other plant species in an area

• disrupt waterfowl and neo-tropical migratory bird flight patterns and nesting habitats

• cost millions of dollars in treatment and loss of productivity to private land owners

Invasive weeds can also deter waterfowl, as explained in the brochure: When Weeds Move In, Waterfowl Move Out

Above, Yellow Starthistle is unpalatable to wildlife and impenetrable for hikers and other recreationists.  Photo by Steve Dewey, Utah State University.

Below, the rare Calachortus found in Hells Canyon, Idaho. Its habitat is under attack from Yellow Starthistle.