What is a noxious weed?
According to the 1974 US Noxious Weed Act (2010
Amendment), noxious weeds are 'those plant species
designated as such by the Secretary of Agriculture,
Secretary of the Interior, or by State law or regulation.
Generally, noxious weeds will possess one or more of the
characteristics of being aggressive and difficult to manage,
parasitic, a carrier or host of deleterious insects or disease,
and being non-native, new to, or not common to the U.S. or
What does it mean to be classified a noxious weed?
Once a plant is designated a noxious weed by the Secretary of Agriculture, the movement of all such
weeds in interstate or foreign commerce is prohibited except under permit.
What else did the Noxious Weed Act of 1974 do?
Authority to inspect, seize and destroy products, and to quarantine areas, if necessary to prevent the
spread of such weeds was also given to the Secretary of Agriculture by the Noxious Weed Act. Federal,
State and local agencies, farmers associations and private individuals in measures to control, eradicate, or
prevent or retard the spread of such weeds were also given the ability to coordinate their efforts.
What is the difference between a noxious weed and an invasive species?
A noxious weed will possess one or more of the characteristics of being aggressive and difficult to manage,
parasitic, a carrier or host of deleterious insects or disease, and being non-native, new to, or not common
to the U.S. or parts thereof.
An invasive species are those species whose introduction does, or is likely to, cause economic or
environmental harm or harm to human health.
Why are there both Federal and state noxious weeds?
A Federal noxious weed designation means the plant species is prohibited everywhere. States may
designate species separately, even those not on the Federal List, in order to respond to more localized
EDDMapS. 2013. Early Detection & Distribution Mapping System. The University of Georgia - Center for Invasive Species and Ecosystem
Health. Available online at http://www.eddmaps.org/; last accessed January 17, 2013.
USDA PLANTS Database