Ecological effects of invasive species

Leafy spurge (Euphorbia esula L.; Euphorbiaceae) is a noxious weed accidentally introduced from Eurasia into North America in the late 1800s and early 1900s via multiple shipments of contaminated crop seed. It has spread extensively throughout pasture, rangeland, and natural areas in the Great Plains, inflicting substantial economic and ecological damage. Leafy spurge is unpalatable to most domestic and native ungulates and thus reduces carrying capacity of both rangeland and natural areas. In the four-state region including Montana, North Dakota, South Dakota and Wyoming, costs due to control and reduced forage availability were estimated at $144 million annually. Department of Interior land managers will treat more than 100,000 acres [...]