Early Detection Watch List of Nonnative Invasive Species of
Southern Forest and Grassland Ecosystems - June 2008

Compiled by the USDA Forest Service Regional Task Force for
the Assessment of Nonnative Invasive Species of Southern Forests

List Purpose

Prevention of entry and Early Detection and Rapid Response (to eradicate) are the most cost effective means to stop invasions before they get started. The listed species are recognized as severe potential threats to Southern Forests and Grassland Ecosystems as determined by reliable lists and databases. The invasive species listed are not currently in the Southern Region or only present in very limited occurrence. Vigilance will be required to prevent and detect their entrance and to stop the spread of existing populations. Early Detection and Rapid Response networks at the regional and State levels are critically needed to effectively detect entrance and spread followed by organized cooperative eradication and containment programs and strategies.

Imminent Threats Currently In The Eastern United States

Subject Name Scientific Name Type Federally Listed
giant cane toad (in FL) Bufo marinus Amphibians
longnose crayfish (in Sequatchie River bordering GA, TN, NC, and VA) Cambarus longirostris Crustaceans
rusty crawfish (in Lake States and TN) Orconectus custicus Crustaceans
emerald ash borer (in Midwest and MD and recently IL) Agrilus planipennis Insects
Asian longhorned beetle (NYand NJ) Anoplophora glabripennis Insects
sirex woodwasp (in Northeast) Sirex noctilio Insects
European pine shoot beetle (in Lakes States and WV) Tomicus piniperda Insects
New Zealand mudsnail (in far West and Great Lakes) Potamapyrgus antipodarum Mollusks
squarrose knapweed (in West and MI) Centaurea virgata ssp. squarrosa Plants - Forbs
mourningbride (in far West, Northeast, and 2 counties in eTX) Scabiosa atropurpurea Plants - Forbs
velvet crabgrass (only in wTX) Digitaria velutina Plants - Grass/Grasslike Yes
ribbed muraingrass (in MD) Ischaemum rugosum Plants - Grass/Grasslike Yes
dalmatian toadflax (entire US and only AR in SE) Linaria dalmatica Plants - Grass/Grasslike Yes
Wavyleaf basketgrass (in MD) Oplismenus hirtellus ssp. undulatifolius Plants - Grass/Grasslike Yes
panic liverseed grass (in AR, NM, TX and MD) Urochloa panicoides Plants - Grass/Grasslike Yes
butterfly bush (planted in South with rare escapes) Buddleja davidii Plants - Shrubs
pumpwood (in FL) Cecropia schreberiana (C. peltata) Plants - Trees

In Continental United States but not in the Eastern United States

Subject Name Scientific Name Type Federally Listed
sudden oak death (in CA, WA, and OR) Phytophthora ramorum Fungi
sticky snakeroot (in CA and Hawaii) Ageratina adenophora Plants - Forbs Yes
three-cornered jack (in CA) Emex australis Plants - Forbs Yes
pickerel weed (in CA and Hawaii) Monochoria vaginalis Plants - Forbs
kikuyugrass (in CA, PR, Virgin Islands and Hawaii) Pennisetum clandestinum Plants - Forbs Yes

Not In The Continental United States

Subject Name Scientific Name Type Federally Listed
common scinax, red snouted treefrog (only in Puerto Rico) Scinax rubra Amphibians
Phytophthora disease of alders (not in US) Phytophthora alni spp alni Fungi
alderdecline (not in US) Phytophthora kernoviae Fungi
Asian gypsy moth (not in US) Lymantria dispar Asian biotype Insects
Mediterranean clone of caulerpa (not in US) Caulerpa taxifolia Plants - Aquatic Yes
anchored waterhyacinth (only in Puerto Rico) Eichhornia azurea Plants - Aquatic
oxygen weed (not in US) Lagarosiphon major Plants - Aquatic Yes
African boxthorn (not in US) Lycium ferrocissimum Plants - Aquatic Yes
nardoo (only in Hawaii) Marsilea crenata Plants - Aquatic
monochoria (not in US) Monochoria hastata Plants - Aquatic Yes
arrowhead (not in US) Sagittaria sagittifolia Plants - Aquatic Yes
eared watermoss, giant salvinia (only in Puerto Rico) Salvinia auriculata Plants - Aquatic
giant salvinia (not in US) Salvinia biloba Plants - Aquatic
giant salvinia (not in US) Salvinia herzogi Plants - Aquatic
aeginetia (not in US) Aeginetia spp. Plants - Forbs Yes
alectra (only in Puerto Rico) Alectra fluminensis Plants - Forbs
wild safflower (not in US) Carthamus oxyacanthus Plants - Forbs Yes
pilipiliula (only in Hawaii) Chrysopogon aciculatus Plants - Forbs Yes
swamp stonecrop (not in US) Crassula helmsii Plants - Forbs Yes
lightening weed, alfombrilla (not in US) Drymaria arenarioides Plants - Forbs Yes
cape tulip (Cultivated, or not in the U.S.) Homeria spp. Plants - Forbs Yes
jointed prickly pear (not in US) Opuntia aurantiaca Plants - Forbs Yes
borreria (not in US) Spermacoce alata Plants - Forbs Yes
water-aloe (not in US) Stratiotes aloides Plants - Forbs
golden false beardgrass (not in US) Chrysopogon aciculatus Plants - Grass/Grasslike Yes
African couchgrass (not in US) Digitaria abyssinica Plants - Grass/Grasslike Yes
Asian sprangletop (not in US) Leptochloa chinensis Plants - Grass/Grasslike Yes
serrated tussock grass (not in US) Nassella trichotoma Plants - Grass/Grasslike Yes
longstamen rice (not in US) Oryza longistaminata Plants - Grass/Grasslike Yes
red rice (not in US) Oryza punctata Plants - Grass/Grasslike Yes
wild sugarcane (not in US) Saccharum spontaneum Plants - Grass/Grasslike Yes
Malabar melastome (only in Hawaii) Melastoma malabathricum Plants - Shrubs
giant false sensitive plant (not in US) Mimosa diplotricha (M. invisa) Plants - Shrubs Yes
shrubby blackberry (not in US) Rubus fruticosus Plants - Shrubs Yes
wild raspberry, ellkek (not in US) Rubus moluccanus Plants - Shrubs Yes
heartleaf hempvine (not in US) Mikania cordata Plants - Vines Yes
bittervine (not in US) Mikania micrantha Plants - Vines Yes

Data Sources

The June 2008 version was developed through study and compilation from existing lists and databases. Selected for listing were those species that pose threats to Southern Forest and Grassland Ecosystems. The source lists and databases were the Global Invasive Species Database, USDA NRS PLANTS Database, the Federal Noxious Weed List, the Lacy Act Prohibited List of Injurious Wildlife, USDA Animal and Plant Health Inspection Service website database, NatureServe's U.S. Invasive Species Impact Rank (I-Rank), the North American Forest Commission's ExFor Risk Assessments, the University of Georgia's Bugwood Network's web database, The National Agricultural Pest Information System's Pest Tracker, and the US Geological Survey's Nonindigenous Aquatic Species web database. Plant names are according to PLANTS Database. This list will be updated as other invasive species are identified as potential threats.


For more information, submission of review comments, and for reporting new and potential invasives of the Southern Region please contact Alix Cleveland, Southern Region NNIS Coordinator, John Taylor, Integrated Pest Management Specialist, or James H. Miller, Research Invasive Species Ecologist. OR any member of the Task Force.