Mulching or weed wiping instead of spraying and training farmers on buffer zones are all measures driving a decline in the concentration of rush spray found in the Larah catchment in Co Cavan, the EPA Water Conference heard last Wednesday.

Integrated catchment manager with Uisce Éireann Lorraine Gaston explained that farmers participating in the catchment’s voluntary water protection project were provided with free environmental management plans and advice.

All farms which required pesticide storage units were provided with them, 14 farms received a mulching and weed wiping service and 15 farms received watercourse fencing with an alternative drinking source.

Gaston said that the active ingredient in many rush sprays, MCPA, poses a higher risk to water quality than the targeted use of glyphosate in weed wipers, while mulching can help suppress the spread of rushes and stop the spread of seeds.

The Larah river’s MCPA load has reduced between 2022 and 2024, with 70% of farmers reporting to have changed the way they use pesticides.