Slugs in Conservation Tillage Corn and Soybeans in the Eastern Corn Belt

Slug problems have increased in frequency as conservation tillage has become a more widely adapted practice for production of corn, Zea mays (L.), and soybean, Glycine max (L.) Merrill, in the Midwest. Because of the increasing concern about slug damage to these crops, we initiated studies to aid growers in management of this serious pest. Slug populations were sampled in conservation-tillage fields in seven counties in Ohio from 1994–1996 to determine the species that were present in field crops and to gain insights into their life histories and damage potential. Four slug species were collected in numbers sufficient to be considered of potential economic importance. The predominant species in population size and geographic range were Deroceras reticulatum (Müller), followed closely by D. leave (Müller). Both species were common in most fields. The third most numerous slug species was Arion subfuscus (Drapamaud). Although this species was found in fewer fields, it was often collected in very large numbers. The fourth slug. A. fasciatus (Nilsson), was found only in two counties. We observed juvenile D. reticulatum causing the most damage by their feeding in late-May and in June. Damage caused by the other species was not as evident, with the possible exception of A. subfuscus causing stand loss in soybeans.