The growing influence of the EU’s Sustainable Use Directive will force many grassland farmers to use contractors for most – if not all – spraying operations, according to Dow AgroSciences’ Biology Team Leader Andy Bailey.

"The registration process alone, that is associated with the implementation of the directive, will drive farmers in this direction," he said.

"And this is already happening. A recent survey carried out on our behalf in the UK indicates that the proportion of livestock farmers opting to use contractors for spraying purposes has risen from 30% to 50% over the past five years."

Bailey predicted that the coming years will see the significantly greater adoption of low-drift spraying systems within the grassland sector.

"This will centre on the use of air inclusion, as opposed to flat-fan nozzles. And again this will be another factor driving the direction of travel towards contractors, where grassland spraying is concerned.

Contractors can quite easily switch the nozzle configurations on their sprayer booms. They are set up to do this; grassland farmers are not.

Bailey said that there would be increasing pressure from the market to reduce the volumes of water used in grassland spraying systems.

"In our own case, trials have confirmed that it is feasible to reduce tank volumes from 300L to 200L with two of our herbicides, using air-inclusion nozzles.

"The environmental benefits of using low-drift spraying systems and reduced water volumes are obvious."

Bailey said that he could not speak on behalf of other herbicide manufacturers, but gave a strong indication that a general move towards a reduction in grassland spray volumes across the board would become a reality.

The Dow biologist confirmed that broadleaf weeds in grassland should only be treated when there is sufficient leaf cover.

"Spraying on a field basis should only be considered if the weed infestation accounts for more than 5% of the total ground area," he explained. "Lighter infestations should be tackled on an individual plant basis."