Invasive Species
An "invasive species" is defined as a species that is 1) non-native (or alien) to the ecosystem under consideration and 2) whose introduction causes or is likely to cause economic or environmental harm or harm to human health. A wide variety of plant species, estimates range from 5,000 to 50,000, have been introduced to different ecosystems in the United States both intentionally and unintentionally. Many of these plants have become established in the wild. A lack of natural predators and pathogens often allows these species, especially in disturbed areas, to out-compete and replace native vegetation. Many of the natives that are being over-run provide critical food and habitat for wildlife. Invasive plants are estimated to infest over 100 million acres in the United States, and they expand their range by 3 million acres each year (BLM). Invasive species are not only costing our environment, but Americans spend $137 billion each year on control. Some species are a more prevalent problem in the metro area and special attention should be given to them.
