Trees for Tennessee Landscapes - Maintaining and Protecting
Invasive, exotic plants can cause significant displacement of native vegetation. But exactly what are exotic plants? What makes them invasive? To find out, let’s start with some basic definitions.
The vegetation historically found in a local area is termed native vegetation. These plants have traditionally been found in the area and are well-suited to maintain themselves in their environs. Exotic plants are those plants found in a particular area, but which originate from another continent or country. These plants can also be referred to as non-native. However, non-native plants are not always exotic. Non-native plants may also be native elsewhere in the same country, but not found in the local area. For example, redwoods are native to California and would be non-native in Tennessee, but not exotic. Invasive plants are plants, native, non-native or exotic, that can cause significant ecological or economic damage. Invasive plants can displace more ecologically and economically valuable plants. These plants are typically characterized by a rampant rate of spread. This rate of dispersal is due to both human activity and vegetative characteristics. Humans assist in the dispersal of plants by moving plant materials to and from locations. Humans also cause significant disturbances to native plant communities that provide opportunities for the establishment of exotic and/or non-native invasives. The seeding and sprouting characteristics of the plants also significantly contribute to the rate of dispersal. Though a negative term, “invasive” plants can also be native plants that we usually do not consider to be a problem. Examples of this type of native plant are sumac (Rhus spp.), poison ivy (Toxicodendron radicans) and redbud (Cercis canadensis).
"SP627 Identification and Control of Non-native Invasive Forest Plants in Tennessee," The University of Tennessee Agricultural Extension Service, SP627-14M-9/04 R12-4910-045-001-05 05-0062, http://trace.tennessee.edu/utk_agexfores/75