Invasive Plant Removal
One of the key activities of habitat restoration is the removal of non-native plants, especially those that are of the highest degrees of invasiveness. You will find resources about invasive plants and how to control them throughout our site, and chapter activities throughout the year may focus on this topic. This page only attempts to summarize some of the key resources.
About Invasive Plants
In conversations about plants, learn to make the distinction between “aggressive” plants and “invasive” plants. Any plant, whether it be native or non-native, can be “aggressive,” and in some applications, this can be a desirable aspect for a native plant. We only use the term “invasive” for non-native plants, and even their degree of aggressiveness can vary greatly.
A list of invasive plants is maintained by the Georgia Exotic Plant Pest Council: http://www.gaeppc.org/list/. Note that the lower the category, the more we are concerned about the invasiveness of the plant, and these tend to be “aggressive” and “invasive.”
In addition to the information below, there are two detailed articles from Heather Brasell about invasive plant control:
Removal Methods
Many people, including many GNPS members, feel strongly about the use of herbicides for the eradication and control of invasive plants. This is a long topic in itself, and here we list only some broadly accepted facts:
- Removing invasive plants will in short order allow native plants to thrive in the same area, as long as the disturbance of the environment is minimized.
- Extensive use of herbicides can be an excessive disturbance.
- Significant digging can disrupt soil ecology, also acting as an excessive disturbance.
- Careful pulling of invasive plants, with minimal soil disturbance OR cutting of plants at the soil line are the best way to control them, even though this may require repeated efforts because of the remaining roots. But plants grow back smaller, weaker, and with less root attachment.
- An alternative to pulling, for some plants, can be repeatedly disturbing them. English ivy is one plant that does not like to be physically disturbed in any way. If you walk on it enough, it will die. If you can weed-whack it (using a string trimmer or a blade trimmer) or even mow over it repeatedly, it will eventually die. Or after several repetitions, sprouts can be hand-pulled more easily with less soil disturbance than if you pull mature vines.
- Surveys of most large-scale efforts in invasive plant removal show that the larger the project, the more iikely that some use of herbicides was warranted.
- Cutting larger plants and painting the cut stems with herbicide is an effective technique with little effect on the surroundings.
- Mowing of annual invasive plants, prior to them going to seed, is an effective alternative to spraying them with herbicide.
Calendar of Activities
Dec-Jan:
- Privet stands out with evergreen foliage. Pulling it after 2-3 days of rain can be surprisingly easy, even for larger plants.
- Mahonia and elaeagnus are more stubborn, but this is also the best time to spot them and treat with the cut-and-paint herbicide technique, if necessary.
- English Ivy is similarly obvious, and a surprising amount of it can be pulled in 30-60 minutes. Do not obsess about missed roots — soil disturbance should be minimized, and you can return later to a smaller task.
Jan-Feb:
- Japanese honeysuckle starts to leaf out, making it easy to spot. It is a tough vine and lends itself to pulling.
March-May:
- Invasive shrubs, trees, and vines make their presence obvious as they bloom. These flowering invasives include princess tree, Bradford pear, privet, and wisteria. For large, strongly rooted plants, consider that cutting and painting with herbicide may be less of an ecological disturbance than digging and pulling.
June-July:
- Consider mowing, as close to the ground as possible, any areas with annual invasive grasses, before they have gone to seed.
GNPS Habitat Certification
Certifying your property as a GNPS Native Plant Habitat includes invasive removal, as well as not cultivating serious invasive plants in even the smallest amounts. Explore the possibility of certification at the GNPS Native Plant Habitat Certification page.