Invasive noxious weeds have been described as a raging biological wildfire – out of control, spreading rapidly, and causing enormous economic losses. Millions of acres in North America have been invaded or are at risk of being invaded by weeds, including cropland, pastures, rangelands, forests, wilderness areas, national parks, recreation sites, wildlife management areas, transportation corridors, waterways, wetlands, parks, golf courses, even yards and gardens. Noxious weeds are capable of spreading at rates of up to 60% annually (Smith et al. 1999).
Devastation caused by noxious weeds is enormous. Economic losses from weeds exceed $30 billion (Pimentel et al. 2005) annually in the United States, and the cost continues to grow. Weeds often reduce crop yields, and can damage watersheds, increase soil erosion, negatively impact wildland plant and animal communities, and adversely affect outdoor recreation.
