Widespread infestations often cannot be completely controlled. There are too many neglected places on the landscape where invasive plants can thrive and spread. But not every weed has filled every niche, and there are still many sites where the removal or suppression of invasive species will protect nearby uninvaded areas.
Parks, nature preserves, privately-held conservation easements, and corridors of uncultivated land are typical candidates for invasive plant surveys and management. These are sites where the removal of invasive plants will make a difference. The same approach holds true for suburban yards and gardens.
Managing invasive plants is all about scale and scope. Homeowners or stewards of small properties can use mechanical methods quite effectively because they can put more time and regular effort into physical plant removal. For persistent weeds on small parcels, the combination of mechanical removal to deplete the plants’ root systems, followed by minimal applications of herbicide, followed by reseeding or planting of appropriate native species will be successful.
Site-based approaches are often used in high-value, relatively intact natural areas. In this case, all (or most) invasive species are removed from a defined area, including likely pathways of spread, but not necessarily from adjacent sites.
Always tailor the treatment methods to the site being managed.
A species-based approach aims for complete removal of a species from an area. The target species is searched for and removed wherever it is found. This is appropriate for early detection projects, or to prevent the establishment of invasive plant populations at new sites.
In reality, invasive plant management happens along a continuum of site-based to species-based management.There may be places where a manager will remove some widespread species but not others, for example, removing garlic mustard but leaving vinca. At the same location, however, he or she might diligently search for the appearance of Japanese stiltgrass to prevent its establishment.
Knowing when to apply either strategy is a matter of experience. Learning how to read the natural landscape is one of life’s great pleasures. The only sure way to learn plants and plant communities is to wade deep into nature, observing and remembering plants (and other life forms), and meeting them species by species. It’s the same process as meeting and remembering people, only quieter. It never gets old, or boring, and it is a year-round pursuit.
Tallamy, Douglas. Bringing Nature Home.
Darke, Rick and Douglas Tallamy. The Living Landscape: Designing for Beauty and Biodiversity in the Home Garden.