One of Mid-west most common pest. They are nesters, this is why they are so tough to control.

1. BASF Urban Pest Profile Sheet and Treatment Strategy
Odorous House Ant
Common Name: Odorous house ant
Photo Courtesy: National Pest
Management Association
Scientific Name: Tapinoma sessile (Say)
BIOLOGY AND HABITS Odorous house ant colonies are polygynous meaning colonies
contain multiple queens. Colonies can reach 10,000 to 100,000 +
The odorous house ant is fast becoming one of the most commonly
in population. They easily form satellite colonies and are not
encountered ant species throughout the U.S. The odorous house ant
aggressive. They will share workers, brood and food and forage
has the ability to produce such large numbers that it forces other
trails. Field colonies are known to “bud” if disturbed mechanically
ant species out of their natural area by out-competing for natural
or induced chemically by the use of repellent insecticides.
resources such as food and colony nesting areas.
(Disclaimer: The information provided in this pest profile sheet is a partial compilation of Odorous house ants are usually found outdoors. They are adaptive
research material, general pest management strategies and general information on this
pest. Pest Management Professionals must follow label directions for insecticides used and opportunistic nesters and exploit many habitats. In the field
for ant control. BASF assumes no liability or responsibility for specific control situations they build shallow nests in soil, logs, stumps, under stones, leaves,
in the control of odorous house ants.)
firewood, boards, beneath bark and inside hollow voids of dead or
The odorous house ant, Tapinoma sessile (Say), is a native species decaying limbs of trees. They will move indoors to avoid perils of
that occurs throughout the United States. It ranges from Canada to inclement weather such as heavy rain, cold temperatures or drought
Mexico but is rarely found in the southwestern desert areas. It has conditions. In structures, nests are built in wall voids, around hot-water
been found at sea level and in areas located at 11,000 feet above pipes and heaters, beneath floors, crawl spaces, and almost any
sea level. areas where the opportunity presents them to build a colony or
satellite colony. They can be found foraging in temperatures as
The odorous house ant is easy to recognize. It is a small monomorphic low as 50 degrees Fahrenheit. They will forage during the day
(one sized worker) ant approximately 1/8” (~3 mm length). The thorax as well as the night.
continued
is uneven and the node is hidden by the abdomen; barely visible. It has
a 12 segmented antenna with no club. There are no circle of hairs on
the tip of its abdomen and it has no stinger. When crushed it gives off
a peculiar odor similar to a rotten coconut.

2. BASF Urban Pest Profile Sheet and Treatment Strategy
Odorous House Ant
They prefer sweet-based foods and honeydew from homopterous Phantom ® termiticide-insecticide is a
insects such as aphids, leaf hoppers, scale insects, which has been non-repellent insecticide that provides
their primary food source long before man-made sucrose type sweets. excellent control inside for odorous house
They will feed on proteins, grease and dead and live insects. Like ants. The label also allows for exterior
most ants, they tend to change their food preferences in early spring, applications where ants enter the structure.
summer and winter, switching from proteins after over-wintering to Since Phantom is a non-repellent and does not move or “bud” the
carbohydrates and sugars in summer months. colonies; it is the liquid residual product of choice inside for ant control.
CONTROL Termidor® termiticide-insecticide is the product
of choice for the perimeter of the structure, where
Control starts with identification and then a thorough inspection to
ants enter the structure, where they nest and
determine the extent of infestation of odorous house ants. Attention
where ants trail. Termidor will transfer from the
must be made to indoor areas, outdoor areas and areas outside and
foraging workers back to the other members of the colony and will
away from the structure. This ant can be classified as arboreal (living
provide long residual control.
in trees, shrubs, bushes and outdoor plantings), subterranean (soil
areas beneath mulch and ground cover), and structural (in homes,
Control depends on what you find during your inspection; especially
offices and buildings) and since large numbers are encountered, PMPs
when you determine the number of odorous house ants you are dealing
may not obtain complete control just by treating in and around the
with. You can get excellent initial control of odorous house ants but
perimeter of the structure. Control considerations may include lawn
extremely large numbers of ants can wear down and or overcome
and tree applications when numbers in the tens to hundreds of
residual insecticides just placed around the perimeter of structures.
thousands are encountered.
If you encounter this situation you should consider using insecticides
in lawn areas where large numbers of ants are trailing or nesting
A combination approach is probably the best method to eliminate
and especially in trees, shrubs and plantings where odorous house
these ants. Protein and sugar-based ant baits are effective tools for
ants are typically found in the summer months. It is best to use an
control; however keep in mind these ants will change their feeding
outdoor product that is registered for lawn, tree and shrub use and
habits throughout the year and prefer the natural foods they find
a non-repellent. Also check with your State Pesticide Enforcement
outdoors. Using baits away from the structure in the summer could
bureau to see if additional training, licensing and/or certification is
draw ants away while using baits in the winter months inside could
necessary when applying pesticides to lawns, trees and shrubs.
help control indoor colonies.
Selected References Additional References and Education Information
• NPMA Scientific Field Guide; http://www.pestworld.org • University of Florida, Department of Entomology
• Mallis Handbook of Pest Control Ninth Edition; http://www.pctonline.com • TAMU, Entomology Department
• Scientific Guide to Pest Control Operations • University of Kentucky, Department of Entomology
http://www.pestcontrolmag.com/pestcontrol
Editor: William A. Kolbe, BCE, Market Development Specialist,
BASF Specialty Products
Phantom is a registered trademark and the Phantom logo is a trademark of BASF. Phantom is
not registered for cockroach in California. Termidor is a registered trademark and the Termidor
logo is a trademark of BASF. Termidor is not labeled for use in N.Y. ©2006 BASF Corporation.
All rights reserved.
Always read and follow label directions.