1980’s: Brunswick River Blackberry Spraying. Pesticide detected: Triclopyr.

Herbicide residues in flowing streams (unpublished report)

A large proportion of Blackberry infestations occur very close to streams or waterbodies. Therefore, herbicide control measures have the potential to contaminate the water body, at the time of spraying, and soon after. This project was designed to measure the potential of glyphosate, triclopyr and picloram herbicides to contaminate the Brunswick River after a simulated Blackberry spraying operation.

Samples of water and sediment were taken at the site of application and 20 m downstream at 1 minute intervals to 5 minutes after spraying, then 20, 60 and 120 minutes after, and 1 week later.

Analysis of the samples showed that no detectable glyphosate or picloram residues were present in either the water or sediment, and that triclopyr was not found in the sediment. Triclopyr residues were found in the water, 1 minute after spraying and 20 m downstream at a maximum level of 0.6ug/L. These levels declined to <0.02 ug/L (Limit of Detection) after sixty minutes.

P39 Monitoring Pesticides – A Review. A Report to the Environmental Protection Authority by Peter A Rutherford. December 1989