Here you go Adam, from invasivespeciesinfo.gov. There are various definitions and some states have lists of plants that persist as "invasive" and others have true invasives. Overall the number of actual "invasives" is relatively limited. Section 1. Definitions. (a) "Alien species" means, with respect to a particular ecosystem, any species, including its seeds, eggs, spores, or other biological material capable of propagating that species, that is not native to that ecosystem. (b) "Control" means, as appropriate, eradicating, suppressing, reducing, or managing invasive species populations, preventing spread of invasive species from areas where they are present, and taking steps such as restoration of native species and habitats to reduce the effects of invasive species and to prevent further invasions. (c) "Ecosystem" means the complex of a community of organisms and its environment. (d) "Federal agency" means an executive department or agency, but does not include independent establishments as defined by 5 U.S.C. 104. (e) "Introduction" means the intentional or unintentional escape, release, dissemination, or placement of a species into an ecosystem as a result of human activity. (f) "Invasive species" means an alien species whose introduction does or is likely to cause economic or environmental harm or harm to human health. (g) "Native species" means, with respect to a particular ecosystem, a species that, other than as a result of an introduction, historically occurred or currently occurs in that ecosystem. (h) "Species" means a group of organisms all of which have a high degree of physical and genetic similarity, generally interbreed only among themselves, and show persistent differences from members of allied groups of organisms. (i) "Stakeholders" means, but is not limited to, State, tribal, and local government agencies, academic institutions, the scientific community, nongovernmental entities including environmental, agricultural, and conservation organizations, trade groups, commercial interests, and private landowners. (j) "United States" means the 50 States, the District of Columbia, Puerto Rico, Guam, and all possessions, territories, and the territorial sea of the United States. --- On Thu, 4/8/10, Adam Fikso <email@example.com> wrote: From: Adam Fikso <firstname.lastname@example.org> Subject: Re: [pbs] "invasive" To: "Pacific Bulb Society" <email@example.com> Date: Thursday, April 8, 2010, 5:57 AM How about "liberally encroaching? ., And re the definition, Boyce-- can you specify the legal parameters so we can learn how not to use the term?