The red imported fire ant, Solenopsis invicta (Buren), is a widely distributed pest of the southern United States. The ants are notorious for their painful, persistent stings and in areas with clay-like soil their mounds can be very large and hard, capable of damaging farm equipment or contaminating harvests. A native of South America, 5. invicta's range in North America has expanded, apparently unchecked by natural enemies for approximately 40 ...