By Vicky Boyd

California fruit and vegetable growers will soon have another option in their meager toolbox of soil-treatment options.

In late December, the California Department of Pesticide Regulation registered the soil fumigant methyl iodide, which is marketed as Midas by Cary, N.C.-based Arysta LifeScience North America LLC.

The department announced the registration Dec. 1 but had to wait until emergency regulations that designated the fumigant a restricted-use product took effect later in the month.

DPR director Mary-Ann Warmerdam called methyl iodide the “most evaluated pesticide in the department’s history.”

“In this case, the process has been more complex because of methyl iodide’s toxicity as well as because of the intense public interest,” Warmerdam said in a telephone press conference.

Jeff Tweedy, who heads Arysta’s business development and regulatory, says he is pleased with DPR’s registration of Midas and called it a “step in the right direction.”

The company plans a full launch of the product in California during the first quarter of 2011.

Realistically, Tweedy says, California’s fumigation season ended in October and won’t begin again in earnest until March or April, depending on the weather.

The U.S. Environmental Protection Agency registered methyl iodide as a replacement for methyl bromide in 2007. Since then, 47 other states have registered methyl iodide.

The use of methyl bromide is being phased out, because many scientists classify it as an ozone depleter.

California will require the most stringent mitigation measures of any state for methyl iodide, Warmerdam says.

Use rates in California, for example, cannot exceed 100 pounds per acre compared with the EPA limit of 125 pounds per acre, she says.

In addition, only licensed commercial applicators who have completed a stewardship training program will be allowed to apply methyl iodide.

At the moment, California will not impose township or county use caps on Midas as it has on the soil fumigant Telone, Warmerdam says.

But she says county agricultural commissioners will be able to impose even stricter measures than the state requirements, based on local conditions.

California initially proposed registering methyl iodide in April 2010 after DPR scientists reviewed more than 175 studies about the fumigant’s potential health and environmental effects.

Because of public outcry, the department twice extended the 30-day comment period. It received more than 50,000 public comments.

DPR also convened two internal review panels as well as an independent review panel to further examine the product, Warmerdam says.