Effects of removal of Tradescantia fluminensis on Powelliphanta traversi and other invertebrates

This study was initiated owing to concern that removal of the invasive ground cover weed Tradescantia fluminensis may adversely effect the rare giant predatory land snail Powelliphanta traversi. From field trials using hand removal and herbicide spraying, it was considered that graduated control of Tradescantia with concomitant replacement of native ground cover could be of benefit to P. traversi and other ground-dwelling invertebrates. Grazon herbicide (active ingredient triclopyr) appears suitable for controlling Tradescantia at sites where P. t. traversi occurs, since the effects of triclopyr on ground-dwelling invertebrates in the field and first generation P. t. traversi in the laboratory were minimal. However, possible effects of triclopyr on subsequent P. t. traversi generations remain untested, and evidence from the literature suggests that there could be some detrimental effects. Similarly, the effects of triclopyr on the presumed earthworm prey of P. t. traversi remain untested.