On September 25, 2007, the governor’s Agricultural Best Management Practices Committee revised its rule requiring that farmers reduce the particulate matter or dust pollution created by agriculture in Maricopa County. The change doubles the number of best management practices (BMPs) farmers must implement, provides five additional BMP choices, and expands the area where producers must implement the BMPs. Farmers in the valley must meet the new requirements by December 31, 2007.

“Although agriculture only contributes about 3 percent of the total amount of dust pollution in Maricopa County, we want to make sure that farmers are doing their part,” said Dan Thelander, a grain producer from Chandler, Arizona, and committee chairman.

Originally, farmers could choose a total of three BMPs to implement — one from each of the three categories: tillage and harvest, non-cropland, and cropland.* The revised rule will require farmers to implement at least two BMPs per category. The five new management practices include: cessation of night tilling, green chop, integrated pest management, precision farming, and the use of transgenic crops. (see descriptions below)

In addition to expanding the BMP options, the rule also expands the area in which farmers are required to implement these practices to include the western portion of Maricopa County. The changes will be part of the plan to reduce dust by at least 5 percent each year that the Maricopa Association of Governments (MAG) must submit to the U.S. Environmental Protection Agency by the end of the year.

New Best Management Practices:

Integrated Pest Management – Combination of techniques including organic, conventional and biological farming practices to suppress pest problems (reduces number of passes for spraying and need for additional tillage).

Precision Farming – Use of satellite navigation to calculate position in the field (reduces overlap and allows operations during inclement weather and at night).**

Green Chop – Harvesting a forage crop without allowing it to dry in the field.**

Transgenic Crops – Use of GMO or transgenic crops such as “herbicide ready.”

Cessation of Night Tilling – Stopping tilling from 2:00 a.m. to 8:00 a.m. during stagnant air conditions on high pollution advisory days.

*A full listing of all agricultural best management practices is available upon request.

**Pictures available upon request