Invasive Plants

Brome is an invasive plant.

Leafy spurge is an invasive Eurasian perennial introduced into the United States as a contaminant of crop seed in the 1880s and 1890s. It is an invasive plant that is poisonous to cattle and infests more than 2.7 million acres in southern Canada and the northern Great Plains. It typically forms monocultures and because of the latex that occurs in all parts of the plant, it is not consumed by...

Siberian elm are an invasive tree.

The abundance of Russian olive varies across the Western United States; these species can be dominant, codominant, or subdominant relative to native species.

For more than a decade, USGS scientists have been leaders in understanding saltcedar invasion on riparian ecosystems in the southwest including effects on plant communities, water loss, erosion, wildlife use and human recreational resources. Models have been developed that quantify the extent of saltcedar distribution and inform management actions. In addition, USGS is studying the effectiveness...

Cheatgrass and other invasive annual grasses continue to expand into the sagebrush ecosystem in the West and are fueling larger and more frequent wildfires. The life cycle of cheatgrass differs from most native grasses in that it dries out early in the season while native grasses are still green and producing seeds. This fuels fires earlier in the season and cheatgrass spreads quickly following...

Invasive species are costly, disrupt natural ecosystems, and consequently threaten native species. Phragmites, a tall wetland grass, has been a part of U.S. wetlands for many years. However, a strain from Europe, introduced in the early 19th century, aggressively displaces the native strain and has spread across the U.S. and Canada. These aggressive invasive plants form highly dense stands that...

The "Phragmites Management and Variable Great Lakes Water Levels" GeoNarrative presents research by the US Geological Survey and US Fish and Wildlife Service on how Great Lakes water levels affect expansion and management of coastal Phragmites populations.

USGS is working closely with partners in the Bureau of Land Management (BLM), U.S. Fish and Wildlife Service (USFWS), and the Intermountain West Joint Venture (IMJV) to collect and summarize spatial datasets that describe measurable aspects of invasive annual grasses (e.g., biomass or presence) across the western United Stated and beyond. The products developed through this project provide...

The Southern Border Fuels Management Initiative was initiated in 2017 to reduce wildfire risk and improve border security by actively conducting fuels treatments on Department of Interior (DOI) and tribal lands within 100 miles of the US-Mexico border. The initiative supports Executive Order 13855: Promoting Active Management of America’s Forests, Rangelands, and Other Federal Land to Improve...

Using temperature, species occurrence, field-based freeze damage data, and regression analyses for 84 invasive species, researchers at WARC are quantifying the species-specific relationships between minimum temperature and plant presence.

ʻŌhiʻa ( Metrosideros polymorpha ) is the dominant tree in Hawaiian forests, but Rapid ʻŌhiʻa Death (ROD), a newly emerging disease that stands to cause high mortality of this ecologically important tree, may lead to invasions by exotic plants as gaps open in the forest. To better understand if planting of ʻōhiʻa seedlings can be used as a restoration tool, we investigated the survival of ʻōhiʻa...