Doña Ana County has stomped fire ant problem, NM Agriculture Department says

LAS CRUCES — The New Mexico Department of Agriculture is moving to end a 27-year-old federal quarantine in Doña Ana County for red imported fire ants.

These are not the common variety that show up around yards and parks. Red imported fire ants, measuring up to a quarter of an inch in length, are an invasive species known for repeated and painful stings with aggressive colonies that feed on important crops such as corn and hay. The ants can disrupt farm operations and even injure or kill livestock, while their large nests present problems for harvesting and irrigation equipment.

The U.S. Department of Agriculture states on its website that the species was introduced into Alabama from South America, likely between 1933 and 1945, and currently infests 367 million acres in the United States. A map of counties under quarantine shows the vast majority are located from central Texas across the Southeast, plus all of Puerto Rico.

In the Southwest, only Doña Ana County and certain areas of Southern California are under quarantine.

State and federal agencies have been working to prevent the species’ spread from Doña Ana County since 1998, “as a result of positive identifications of red imported fire ant collected during routine surveys,” NMDA’s report stated.

The news was included in a written report to the New Mexico State University Board of Regents, which also serves as the state board of agriculture since the agriculture department is based at the university.

“The quarantine has resulted in increased costs to wholesale plant and turf nurseries exporting out of the county, restrictions on the export of specific agricultural commodities and other items (equipment) that may harbor red imported fire ant,” the report stated.

The USDA’s plant protection and quarantine division worked with molecular biologists at NMSU to apply pesticides, monitor the species and refine strategies for eradicating the pests. For the past three years, the department stated no red imported fire ants have been identified in the county, which is the primary requirement for federal deregulation. Additionally, the nearest areas with known infestations are hundreds of miles away in Texas.

“The issue never bloomed to the point where it was an issue with those people using parks and so forth,” Brad Lewis, director of NMDA’s agricultural and environmental services division, told the Journal. He attributed this in part to New Mexico’s arid climate and ongoing drought, which limit the ants’ range to large irrigated areas.

Yet because they travel easily through states on trucks, farm equipment or in soil, the quarantine restricted the movement of products that could harbor the ants and their eggs.

The burden of compliance likely fell hardest on plant nurseries, Lewis said: “They had the added expense of treating pots and facilities to ensure that any material they shipped out of the county was treated with a pesticide. Most of them treated the grounds with baits and then the Department of Agriculture would survey them and they would get a clean bill of health.”

If the USDA agrees with New Mexico’s data and lifts the quarantine, Doña Ana County would become the first in the country to be deregulated for the species, according to the NMDA, but there was no estimate of how soon the agency will act.