The effects of the herbicide Asulox on non-target bryophytes and pteridophytes

摘要

Control of the weedy fern bracken Pteridium aquilinum (L.) Kuhn, is commonly achieved by spraying the systemic, carbamate herbicide Asulox. The mode of action of Asulox is not well understood, but application of the herbicide in the summer to fully unfurled fronds of bracken prevents the majority of new fronds from emerging the following year. It is recommended that Asulox is applied to bracken with an adjuvant or wetting agent such as the non-ionic surfactant Agral. Use of the adjuvant is sporadic, with some contactors including it in the herbicide mixture, but not others. The application of herbicides in general, and particularly from the air, causes drift onto non-target sites, with the potential to damage non-target vegetation. The amount of drift caused by a spray event can be reduced by a number of measures, including the use of drift-reducing nozzles and the implementation of buffer zones around potentially sensitive areas. The effects of Asulox on some non-target plants, particularly in the form of drift, have been widely studied and several plants, including non-target fern species, have been shown to be sensitive to exposure. There has been a dearth of information on non-target British ferns and other potentially sensitive plants that are prevalent in and around bracken stands e.g. mosses and liverworts (bryophytes), which the work reported herein sought to address. (Abstract shortened by ProQuest.).