About the Weeds of the U.S.

This list was compiled to help our users avoid potentially harmful plants while selecting species for conservation purposes such as creating buffers, improving pastures or wildlife habitat, or restoring degraded landscapes. It was compiled verbatim from sources around the country to provide a comprehensive look at potential problem plants in the U.S. Because this list contains both native and introduced species with diverse characteristics, some plants on it may be suitable for one use and not another depending on the location and other circumstances. This list does not endorse or proscribe the use of any of these species in a particular situation or location, but many have caused serious problems in this country in the past. Therefore, when selecting a species for conservation practices, please consult with your local NRCS office, state or county extension specialists, and others for current and detailed information for your area.

Plants on this list are weedy or invasive, or have the potential to become weedy or invasive, in all or part of their U.S. range. A few do not occur in the U.S., but occur on state or federal noxious weed lists to emphasize their potential to invade and degrade our landscapes. Most are introduced to the United States, while others such as Rocky Mountain iris (Iris missouriensis) and dodder (Cuscuta spp.) are native, but invade managed habitats such as rangelands or agricultural fields. Still others are natives in parts of the country and serious pests in others. For example, smooth cordgrass (Spartina alterniflora) is critical for wetland restoration in the southeast U.S., but is considered highly invasive and destructive in the Bay Area of California, where it is introduced. And many valuable plants are native to the continental U.S., but serious pests in Hawaii.

The USDA NRCS National Plant Data Center compiled this list from several sources (see below). Most of these weedy or invasive plants are on the Federal Noxious Weed List or the noxious weed lists of individual states. Others are found on state resource department invasive plant lists, state Exotic Plant Pest Council lists, or have been identified by university noxious weed specialists. If we have erred in recapitulating any of the source lists, or if you can suggest additional authoritative sources, please contact the National Plant Data Center.