Three-band garden slug
Common names: Three-band garden slug, Valencia slug, Greenhouse slug
Scientific name: Lehmannia valentiana
Counties in California where collected: 29 counties: Alameda, Butte, Contra Costa, Fresno, Humboldt, Imperial, Kern, Kings, Lake, Los Angeles (including Santa Catalina Island), Madera, Modoc, Monterey, Orange, Riverside, Sacramento, San Bernardino, San Diego, San Francisco, San Luis Obispo, San Mateo, Santa Barbara (including Santa Cruz Island), Santa Clara, Santa Cruz, Shasta, Sonoma, Sutter, Tehama, Ventura (including San Nicolas Island) (Roth and Sadeghian, 2006; Mc Donnell et al, 2009).
Ecology: This is a strictly terrestrial slug species unlike other Lehmannia which live in trees (Barker, 1999). It feeds on plants and decomposing wood and is a very serious pest of flowers such as orchids and other ornamentals in greenhouses (South, 1992). Kerney and Cameron (1979) also cite it as a pest of urban gardens. The species appears to be intolerant of a cold climate (Forsyth, 2004).
Description: A medium to large slug, up to 75mm (3") in length (Barker, 1999). The ground color of L. valentiana is very variable but in California it is usually cream but can also be dark brown. The species can be identified by the presence of two distinct, dark ‘tram’ lines on the back often running the full length of the body. There may also be a less distinct median band. However, we have collected many specimens where the bands are broken into spots and others where the lines are very faint (usually in large specimens). The mucus of this species is watery, copious and colorless.