Feeding of slugs (Deroceras sp. and Lehmannia nyctelia) on subtropical pasture species, particularly Kenya white clover (Trifolium semipilosum) cv. Safari.
Field measurements showed that Deroceras sp., a slug, could at times be a serious pest in pastures of T. semipilosum cv. Safari in SE Queensland. At peak infestation (470 slugs/m2), 60% of the leaf area was eaten. In laboratory experiments, T. semipilosum was very palatable to Deroceras sp. and to another slug, L. nyctelia. The latter slug is common in SE Queensland, but is rarely found in T. semipilosum pastures. Both slugs avoided eating the 14 spp. of tropical grasses that were tested. In pot experiments, slug damage depressed the growth rate and competitive ability of T. semipilosum. Slugs destroyed emerging seedlings of both T. semipilosum and T. repens. In controlled-temp. conditions, both slugs thrived better at 12 and 18 deg C than at 6 and 24 deg . At 30 deg Deroceras sp. died whereas L. nyctelia survived.