August 15, 2012
Contact: Ian Foley
(406) 444-9430 

Ag Officials Investigate Invasive Snail  

HELENA, Mont. -- Montana Department of Agriculture and U.S. Department of Agriculture officials are investigating the discovery in Montana of a land-dwelling snail species not previously found in the western United States. 

USDA's Animal and Plant Health Inspection Service confirmed August 9 that terrestrial snails collected about 20 miles southeast of Great Falls were eastern heath snails (Xerolenta obvia), a species native to eastern Europe that spreads by attaching to cargo containers or other conveyances used in international shipping. 

State and federal officials are surveying the surrounding area to determine the extent of the population and what actions might be appropriate. 

"We routinely conduct surveys for invasive pests that could damage crops or the environment. This discovery was unusual because the only other known instance of heath snails in the United States is in Michigan," said state agriculture Director Ron de Yong. 

Eastern heath snails were found in 2001 in Detroit near a heavily trafficked shipping area adjacent to Ontario, Canada, where a larger population of the snails exists. Xerolenta obvia is one of several snail species identified by USDA planning documents as a potential pest of U.S. agriculture, and control measures are recommended. 

Heath snails lay eggs in the soil, infest a wide range of plant species including beans, peas, grapes and weeds, and can contaminate other crops such as grass hay and grain. In eastern Europe, the snails are known to prefer dryland climates. The snails are flat rather than conical, slightly smaller than a dime in diameter, and have white shells with dark brown spiral bands. 

Information about the discovery will be updated via Montana State University's Ag Alert network at Questions about the pest or identification of suspect snails can be addressed to the USDA Plant Protection and Quarantine office in Helena at 406-449-5210 or the Montana Department of Agriculture's Pest Management Bureau at 406-444-9430.