story to find out more.
Chen checks the repellency of specific compounds using a new bioassay he
developed based on digging behavior of fire ants. Click the image for more
information about it.
Ganging up to Stop Fire Ants
Flores December 10, 2004
Fire ants and the U.S. South have been synonymous since the ants'
arrival in Alabama in 1918 aboard merchant ships from South America. The pests
found their way onto land and have been multiplying and migrating ever
Researchers at the Agricultural
Research Service, the chief scientific research agency of the
U.S. Department of Agriculture, are working
diligently to curb the spread of these troublesome pests, which have stung
countless humans and damaged electrical and farm equipment. They even attack
and kill young cattle and other livestock, as well as vulnerable wildlife.
To combat this ongoing problem, scientists in the ARS
Control of Pests Research Unit at Stoneville, Miss., and the
Control and Mass Rearing Research Unit at Starkville, Miss., are conducting
regional integrated management programs in Mississippi, Alabama and Tennessee.
The programs are designed to implement and test biological control agents
against red and black imported fire ants (Solenopsis invicta and S.
richteri, respectively) and their hybrid. Two specific areas are the focus
of the programs: the Natchez Trace
Parkway, maintained by the National Park
Service, and south-central Tennessee's nursery crops production region.
Establishment of biological control agents in central Tennessee may
slow the spread of the ants into nursery areas. Currently, a pathogen and
several species of parasitoid flies--including the decapitating phorid fly from
the genus Pseudacteon--are the most effective known biological control
The Stoneville unit has reared thousands of phorid flies for research
and field releases. One tiny species, P. curvatus, has been successfully
established on black and hybrid fire ants in a multistate release program that
began in 2002. Flies released in two pastures in Clay County, Miss., now occupy
approximately 560,000 acres up to a distance of more than 28 miles from the
Also being implemented is an Integrated Pest Management approach that
combines tactics such as distribution of insecticidal baits with natural
organisms. Chemical bait treatments alone are not sustainable, because fire
ants will reinfest previously treated areas. However, baits can be very
effective, consistently killing more than 90 percent of colonies in an area
when applied correctly.
about this multifaceted fire ant research in the December issue of ARS'
Agricultural Research magazine.