SCDNR-Clemson Helps Curb the Spread of Aquatic Weeds

The South Carolina Department of Agriculture's Noxious Weed Act and associated weed list has received a lot of attention over the years and has been an important tool in preventing the importation, sale and distribution of several nuisance aquatic plant species.

However, many are not aware that similar legislation also authorizes the State Crop Pest Commission at Clemson University to perform a very similar function. The Crop Pest Act (1912) provides the Commission with far reaching powers to "seize, quarantine, treat, or otherwise dispose of the plant pest, host, or article in a manner the commission considers necessary to suppress, control, or eradicate or to prevent or retard the spread of the plant pest" that poses a serious threat to the State's agriculture.

The State Crop Pest Commission is further authorized to promulgate and enforce reasonable regulations to eradicate or prevent the introduction, spread, or dissemination of plant pests. Toward that end, the Commission in 1996 established Regulation 27-135 which identifies a variety of plant and animal species as "plant pests." Fortunately, this list includes all nine aquatic plant species on the State Noxious Weed List, plus all 17 aquatic plant species on the Federal Noxious Weed List.

Enforcement of these regulations is carried out primarily by Clemson University's Department of Plant Industry, a component of the Division of Regulatory and Public Service Programs. Department of Plant Industry district inspectors routinely visit plant nurseries and greenhouses throughout the state to ensure compliance with the regulations. While their emphasis has been principally on terrestrial weed species and insect pests, they have recently expanded their surveys to become more observant of aquatic weed species.

Working closely with the Department of Natural Resources, all five district inspectors and administration staff received a one day workshop on aquatic weed problems in public waters, control operations, problem species, public education efforts, and aquatic plant identification.

"We are pleased to be able to help" says Jack Jackson, Department Director, "Invasive species are a serious problem and we have to work together and pool our resources if we are going to make a difference."

The cooperative effort has already paid off. Giant Salvinia (Salvinia molesta), a particularly noxious aquatic fern, was found in a greenhouse in Aiken County by a Clemson inspector. Following a brief investigation, the owner was informed of the potential danger of the plant and the specimens were immediately and properly disposed of.

Cooperation between the Department of Natural Resources and Clemson University Department of Plant Industry is expected to become more formalized with the completion of a Memorandum of Understanding early this year.

Alternanthera philoxeroides (alligatorweed)
Azolla pinnata (mosquito fern, water velvet)
Egeria densa (Brazilian elodea)
Eichhornia azurea (anchored waterhyacinth)
Eichhornia crassipes (water hyacinth)
Hydrilla verticillata (hydrilla)
Hygrophila polysperma (Miramar weed)
Ipomoea aquatica (Chinese waterspinach)
Lagarosiphon major (Oxygen weed)
Limnophila sessiliflora (ambulia)
Ludwigia hexapetala (water primrose)
Myriophyllum spicatum (Eurasian watermilfoil)

Melaleuca quinquenervia (melaleuca)
Monochoria hastata (monochoria)
Monochoria vaginalis (pickerel weed)
Najas minor (slender naiad)
Ottelia alismoides (duck-lettuce)
Phragmites australis (common reed)
Sagittaria sagittifolia (arrowhead)
Salvinia auriculata (giant salvinia)
Salvinia biloba (giant salvinia)
Salvinia herzogii (giant salvinia)
Salvinia molesta (giant salvinia)
Sparganium erectum (exotic bur-reed)
Trapa natans (water chestnut)