Why are invasive weeds a problem for the BLM?
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 of weed
monocultures-single plat species that over run all others 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
What is a noxious weed?
The term "weed" means different things to different
people. In the broadest sense, it is any plant growing where
it is not wanted. Weeds can be native or non-native, invasive
or non invasive, and noxious or not noxious. Legally, a noxious
weed is any plant designated by a Federal, State or county government
as injurious to public health, agriculture, recreation, wildlife
or property. (Sheley, Petroff, and Borman,1999) A noxious weed is
also commonly defined as a plant that grows out of place
(i.e. a rose can be a weed in a wheat field) and is "competitive,
persistent, and pernicious." (James, et al, 1991).
Are invasive plants the same as noxious weeds?
No. Invasive plants include not only noxious weeds, but
also other plants that are not native to this country. The
BLM considers plants invasive if they have been introduced into an
environment where they did not evolve. As a result, they
usually have no natural enemies to limit their reproduction and
spread (Westbrooks, 1998). Some invasive plants can produce significant changes to vegetation, composition, structure, or
ecosystem function. (Cronk and Fuller, 1995).
References
Cronk, Q., and J. Fuller. 1995. Plant Invaders: The threat to
natural ecosystems. Chapman & Hall. New York
James, L., J. Evans, M. Ralphs, and R. Child, editors.1991.
Noxious Range Weeds. Westview Press. Boulder, CO.
Sheley, R.,J. Petroff, M.. Borman, 1999. Introduction to
Biology and Management of Noxious Rangeland Weeds, Corvallis, OR.
Westbrooks, R. 1998. Invasive plants, changing the landscape of
America: Fact book. Federal Interagency Committee for the
Management of Noxious and Exotic Weeds (FICMNEW). Washington, DC. |
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