© Bruce McNitt/Panoramic Images (Virginia)
Invasive Species in Virginia
New species have been arriving in Virginia from foreign lands since the settlement of Jamestown and continue to arrive with the ongoing rise in global commerce -- but not always for the better. The second greatest threat to Virginia's lands and waters comes from invasive exotic species.
Some exotic species were introduced into the state and spread intentionally, as with multiflora rose and autumn olive which have been used widely as wildlife plantings. Others were established by accident, as with Japanese stilt grass which probably arrived as packing material for porcelain from China.
Most new introductions wither away unnoticed but some, in the absence of their native predators, diseases and competitors, rapidly exploit their new habitats. Exotic species may threaten the survival of native species in several ways. Some exotics, such as kudzu, out compete natives some, such as the gypsy moth, prey heavily on natives that have not evolved adequate defenses; and others, such as the Chinese chestnut, are seemingly harmless, but may be the source of disease (chestnut blight, in this case) that devastates native species.
Slowing the introduction and spread of exotic species is a monumental task that far exceeds the scope of the Virginia Natural Heritage Program. However, the agency contributes to the process in several important ways. When invasive exotic species threaten natural heritage resources, steps are taken to control or eradicate them. With invasive plants, this typically involves using herbicides, mechanical efforts and/or prescribed burning. The program’s extensive data on the distribution of plants across the state are useful for analyzing the spread of exotic species. For example, information gathered in routine vegetation sampling has been used to identify some of Virginia’s most invasive species.
To foster agency collaboration and information sharing to better understand and control exotic species, and to help educate the public, Virginia Natural Heritage staff play a central role in the Virginia Invasive Species working Group. Created in 2006 by Executive Directive 2 (228k PDF) signed by Governor Tim Kaine, the Group provides state leadership regarding invasive species. The Working Group coordinates efforts to prevent invasive species from entering Virginia and to effectively manage those problem species already established in the Commonwealth. The Working Group's first steps have included the implementation of the state invasive species management plan, and the development of a list of high priority invasive species, which is available on their website. In addition to this continually-evolving list, the Virginia Natural Heritage Program, in cooperation with the Virginia Native Plant Society and others, have published fact sheets on the 30 most invasive plant species in Virginia. These fact sheets are available on the Natural Heritage website.
Another example of the Working Group’s efforts to educate and engage the public is a recent symposium on common reed (Phragmites australis) co-hosted by DCR and the Chesapeake Bay Commission. This symposium brought together experts from across the country to share information on this serious wetland invasive.
The Invasive Species Working Group provides a thorough summary of resources on various topics anchored on invasive species biology and management on their website.
Other resources, provided by specific Virginia State government agencies are available as well:
Department of Conservation and Recreation, Virginia Natural Heritage Program Department of Agriculture and Consumer Services, Office of Pest Plant Management
Department of Game and Inland Fisheries
Department of Forestry
Virginia Institute of Marine Science
Virginia Marine Resources Commission