Mustard is about to become a regular sight on Irish cereal farms because it has been identified as the crop most likely to prevent groundwater being contaminated by nitrates during the winter.
At the Teagasc national tillage conference in Carlow, cereal farmers were told they should sow mustard during winter to prevent nitrates flowing off land.
The conference was told by Dr Owen Carton, of the Teagasc Research Centre at Johnstown Castle, that mustard had been identified as the most powerful protection against leaching of nitrates when land is not being used in the winter.
Dr Carton said that mustard, which is not normally grown here, absorbs and holds the nitrates better than any other crop which would be sown after crops have been harvested.
"The alternative is to grow a winter crop but for some operators that would not be feasible," he said.
Dr Carton said it was generally accepted that in some areas, especially areas identified as Nitrate Vulnerable Zones by the Environment Protection Agency, that it would be mandatory for farmers to grow a mustard crop when the land was fallow in the winter.
He said the mustard crop had been found to absorb and hold nitrates more efficiently than any other alternative crop and it would also be cheap to grow. "When the spring crops are being planted, the mustard would just be ploughed back into the earth," he said.
Dr Carton rejected suggestions that cereal farmers were responsible for damaging water in rural areas but accepted that many of the zones identified were also areas where there was cereal growing.
He told farmers attending the conference not to be panicked by reports that they could not farm commercially when curbs on nitrates were introduced.
"If cereal farmers follow the recommendations laid down by Teagasc on fertiliser use, there will be no loss of yield," he said.
Environmental issues dominated this year's conference, which is being held against the backdrop of an EU demand on the Government to introduce severe curbs on fertiliser use.
The head of Teagasc Oakpark's research centre, Mr Jim Burke, said while there had been damage to groundwater supplies from intensive farming and other activities, Ireland was far less damaged than most of the rest of the EU.
"We have experts coming in to us from all over Europe and they are amazed that we still have hedgerows. Most hedgerows have been ploughed out 30 years ago in the rest of the Union," he said.
He said Ireland was still breaching the levels of emissions agreed in the Kyoto agreement and ultimately this could put a major damper on economic development. The main curbs would be placed on industry but farming too would have to play its part in reducing emission levels and this could be achieved by concentrating on biomass crops for renewable energy.