The fertilizer industry is very concerned and engaged in the issue of nitrate contamination in California's groundwater supplies, according to Richard Cornett, communications director for the Western Plant Health Association in Sacramento, a trade group that represents fertilizer companies, manufacturers and retailers.

Regarding a recent UC Davis study on the issue, the fertilizer industry acknowledges the problem of nitrates seeping into California's groundwater but points out that it is important that the public understand that the fertilizer industry has been addressing this issue for many years.

Granted, the new study did note the scope of the problem and the numbers of those people affected by nitrate pollution, along with pointing out financial remedies to deal with the situation, but the general reader might not know that industry has been working hand in glove with agriculture and state agencies in tackling this problem over the past several decades, Cornett noted.

Indeed, it is accurate to state, he says, that had it not been for the research and education funded by the fertilizer industry, to reduce and improve the nitrate situation on agricultural lands in California over the past 30 years, that UC Davis researchers may have reported numbers that greatly exceeded their findings about the extent of the problem and the amount of those residents impacted.

Cornett said to put the nitrate issue into context, it should be pointed out that during the past 30 years the fertilizer industry in California has self-funded research on the issue working in tandem with the California Department of Food and Agriculture. More specifically, CDFA's Fertilizer Research and Education Program (FREP) has concentrated on developing extensive "best management practices (BMPs)" to mitigate contributions from fertilizers. Over the years, with the support of the fertilizer industry, CDFA/FREP has contributed millions of dollars in grant funds to combat the nitrate problem.

This is accomplished through nutrient management projects, and farmers are implementing BMPs that optimize the efficiency of fertilizer usage by matching nutrient supply with crop requirements and to minimize nutrient loses, he said.

Over the years there have been changes in farming practices to reduce nitrate leaching, Cornett pointed out. These include split applications of nitrogen fertilizer which involves the proper amounts of nitrogen and other plant nutrients for vigorous crop growth based on soil and plant tissue testing. Soil moisture sensors are now available that allow for the continuous monitoring of soil water status in the soil profile. Fertigation (fertilizer mixed into irrigation methods) has become more popular for its efficient use of water and nutrients, tremendously reducing leaching and runoff of nitrates.

And, more recently, he continued, there have been new technologies developed, such as the remote sensing of in-season nitrogen status of crops for supplemental fertilization involving corn and wheat, and is presently in development for stone fruit crops and almonds. Crop-specific and sometimes even variety-specific algorithms allow for precise and spatially variable application of the optimum nitrogen rate. Also, progress is being made to determine nitrogen management zones guided by aerial imagery, photography to detect nitrogen stress, and sensors to calculate nitrogen application rates while travelling across the field. As this new technology becomes more established and affordable, its adoption in California will be widely accepted.

Cornett said all this is not written to confuse the reader with a bunch of technical examples put forth by the fertilizer industry to address what it is doing to deal with the nitrate issue, but to reinforce the industry's position that it has been, is, and will continue to work closely with regional water boards, state agencies and California growers in a continuing effort to mitigate nitrate impacts to California groundwater.

As noted in the UC Davis study, Cornett remarked, even if we were to completely eliminate the sources of nitrate in groundwater today, California's Central Valley and the Salinas Valley (heavy ag producing areas) would continue to have a drinking water problem for the next 10 to 30 years, because nitrates can move very slowly through soils to groundwater.

The public should rest assured that the fertilizer industry continues to be at the table with regulators, researchers, and the agricultural community to help find solutions to nitrate leaching in California's groundwaters, he said.

Richard Cornett Western Plant Health Association 916-574-9744 Email Contact