Since Governor Quinn proclaimed May 2012 as Invasive Species Awareness Month, it makes sense to explore exactly what an invasive species is. Is it a weed? Is it a native plant? Where did it come from? Is there any difference between a nonnative, alien species or invasive species? It can all get very confusing.
The Chicago Botanic Garden’s website explains these definitions:
- Invasive - a species, usually nonnative, that establishes itself within existing native plant communities and poses a threat to the integrity of the community.
- Native (also called Indigenous) - a species that was present in North America prior to European settlement or arrived since through natural means of dispersal.
- Nonnative (also called Exotic, Alien, Introduced) - a species brought to North America by humans, either deliberately or accidentally.
- Naturalized - a nonnative or native species from another region of the country, that establishes in disturbed areas and/or native communities.
- Weed - a species that readily spreads, especially in disturbed areas, but generally does not pose a threat to the integrity of native plant communities.
It also states, in part that:
Although invasive plants are almost always not native to a region, it is important to note that most nonnative species are not invasive. In addition, some native species can become invasive.
OK, so it still may be a bit confusing. Learning to identify invasive species to determine if there are one or two lurking in the backyard and keeping them out of the garden is really the point. A couple of websites provide excellent pictures of the current species of concern.
- http://www.invasive.org/illinois/SpeciesofConcern.html - clicking on each species will bring up a full description of the plant, more images and other resources for more information.
- Midwest Invasive Plant Network This site is full of information on invasive species. First, download the brochure titled INVASIVE PLANTS in the Midwest. It gives excellent illustrations and descriptions of the plants on the invasive watch list. Then, download the brochure titled Landscape Alternatives for Invasive Plants of the Midwest. This is full of practical and beautiful suggestions of plants to use as alternatives to invasive species. For example, instead of using invasive Ribbon Grass (Phalaris arundinacea ), it lists Autumn Moor Grass (Sesleria autumnalis), Ice Dance Sedge (Carex morrowii 'Ice Dance') and Variegated Prairie Cord Grass (Spartina pectinata 'Aureomarginata') as alternatives.
With any unwanted plant in the garden, whether weed or invasive, remove as much root as possible to avoid it coming back. Fill these spaces with hardy alternatives and watch your garden grow.