What is a Weed?

The term weed has many different definitions and often means different things to different people. In Weeds of National Forest Lands Of the Northern Rockies - To most land managers, at least in the Pacific Northwest, the term weeds generally implies exotic plants of foreign origin that were deliberately or accidentally introduced. . . .we shall define weeds as those invasive, exotic species of plants that are targeted for control or containment by national forest range management staffs.

Understanding and Managing Invasive Plants in Wilderness and Other Natural Areas - Various terms and definitions for nonnative, invasive species can be found in the literature. According to Reichard and White (2001) an invasive plant is "...one that has or is likely to spread into native flora and managed plant systems, develop self-sustaining populations, and become dominant or disruptive (or both) to those systems

On Feb 3, 1999, Executive Order 13112 was signed establishing the National Invasive Species Council. The order defines an "invasive species" as a species that is (1) nonnative (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.