Weeds

Invasive Weed Management

Cutting weeds at Clear Creek Recreation site.

Weeds are spreading on BLM lands at an estimated rate of 12 percent per year, or 144,000 acres per year. Approximately 1.2 million of the 15 million acres of BLM administered lands in Oregon and Washington are infested with noxious weeds.

One of the BLM's highest priorities is to promote ecosystem health and one of the greatest obstacles to achieving this goal is the rapid expansion of weeds across public lands. These invasive plants can dominate and often cause permanent damage to natural plant communities. If not eradicated or controlled, noxious weeds will continue to jeopardize the health of the public lands and to constrain the myriad activities that occur on public lands.

The BLM works with State, Federal and local parters to reduce the spread of invasive species, with an emphasis on early detection of and rapid response to new invasions in order to reduce the need for larger and more expensive treatments.

Invasive plants (or weeds) are non-native aggressive plants with the potential to cause significant damage to native ecosystems and/or cause significant economic losses.

Noxious weeds are a subset of invasive plants that are county, state, or federally listed as injurious to public health, agriculture, recreation, wildlife, or any public or private property

Of the 121 listed noxious weed species, some of the most prevalent include: yellow starthistle, Scotch broom, Himalayan blackberry, quackgrass, field bindweed, Canada thistle, perennial pepperweed, medusahead rye, St. Johnswort, diffuse knapweed, poison hemlock, English ivy, Scotch thistle, and tansy ragwort.

Noxious weeds and invasive plants enter Oregon and Washington in shipping containers, on vehicles, packing materials, clothing, with other plants or soil, or are brought in intentionally as ornamentals or to accomplish some management objective. They are spread and move great distances by such things as off-road and other vehicles, on camping and other recreational equipment, on pack stock and livestock, in hay and other feed crops, on construction equipment, on the wind, on animals including within feces, and as intentionally moved ornamental plants or inadvertently within the soil of such plants.

Control Measures

Yellow Starthistle attached to vehicle.

One of the most important elements of the BLM's integrated vegetation management approach is raising internal and external awareness of the threats of invasive and unwanted vegetation and promoting prevention actions. The BLM places a management emphasis on preventing the establishment of noxious weeds into weed-free areas. This early detection and rapid response approach involves training employees to identify noxious weeds and to report new infestations so they can be addressed as quickly as possible.

Annually, the BLM treats approximately 2,500 acres of noxious weeds using mechanical methods (chainsaws, chaining, blading, disking, mowing), 2,000 acres using manual removal (hand pulling), 1,500 acres using biocontrol methods (release of insects, pathogens, or other organisms to feed upon, parasitize, or otherwise interfere with a targeted weed species), 2,800 acres using directed livestock (grazing goats) and 12,000 to 14,000 acres using herbicides.

The BLM works closely with private landowners, County Weed Boards, watershed councils, Soil and Water Conservation Districts, Cooperative Weed Management Areas, State agencies and other Federal agencies in an effort to increase weed prevention and treatment effectiveness.

Vegetation Treatments Using Herbicides on BLM Lands in Oregon Record of Decision

Purple Loosestrife flowers.

The Vegetation Treatments Using Herbicides on BLM Lands in Oregon Final Environmental Impact Statement was released on July 30, 2010. The selected alternative (a slightly modified version of Alternative 4) in the Final EIS would add ten of the BLM nationally-approved herbicides west of the Cascades and thirteen herbicides east of the Cascades to the four approved herbicides already in use in those areas. The proposed action would expand herbicide use beyond noxious weed treatments to include: the treatment of all invasive plants; the control of pests and diseases; the control of native vegetation in rights-of-way, administrative sites, and recreation sites; and the treatment of vegetation to achieve habitat goals specified in interagency Conservation Strategies for Federally-listed and other Special Status species. A Record of Decision was issued on October 1, 2010. For more information please visit the Vegetation Treatments website.

Help Slow the Spread of Noxious and Invasive Weeds!

There are many things an individual can do to help prevent the introduction and spread of noxious weeds. First and foremost, become familiar with the noxious weeds in your area and treat them to prevent their spread. Wash your vehicles and equipment before venturing into new areas to prevent tracking weeds into new areas. Report weed sitings on BLM administered lands to the local BLM weed coordinator.