Management Strategies for Subterranean Termites - Urban Insect Pests: Sustainable Management Strategies - page 118

transfer. Most of the newest insecticides
exhibit a dose-dependent relationship for
toxicity. The onset of disorientation and
ataxia occurs faster after exposure to high
concentrations of indoxacarb (Quarcoo et
al., 2010). Termites exposed to low con-
centrations or brief exposures to fi pronil
(Saran and Rust, 2007; Bagnères et al. ,
2009), indoxacarb (Quarcoo et al., 2010)
and chlorantraniliprole (Buczkowski et al .,
2012) experience delayed toxicity (Gautam
and Henderson, 2011; Neoh et al., 2012a).
Similar exposure to imidacloprid (Haagsma
and Rust, 2007) and chlorantraniliprole
(Buczkowski et al. , 2012; Neoh et al. , 2012a;
Puckett et al. , 2011) inhibit feeding.
Chlorantraniliprole is an exception, how-
ever, and does not exhibit a dose-dependent
relationship (Buczkowski et al ., 2012).
In recent years, there has been a trend
towards mixing insecticides with different
modes of action such as neonicotinoids and
pyrethroids for urban pest management
including termite control. It has been sug-
gested that mixtures would combine the
positive attributes of both. When a com-
bination product containing bifenthrin and
acetamiprid is applied to soil, only the
pyrethroid bifenthrin persists for 30 months
(Peterson, 2012). In contrast the neo-
nicotinoid acetamiprid lasts only 7 months.
Like bifenthrin, acetamiprid is a fast-acting
and highly repellent insecticide to tunnel-
ling termites (Rust and Saran, 2008; Smith
et al., 2008).

requiring only quarterly versus the standard
monthly inspections.
The use of baits to control subterranean
termites will gain additional acceptance as
new active ingredients and delivery tech-
nology are developed that reduce costs. The
speed at which baits control colonies is in
part dependent upon the time in which
foragers take to locate bait stations. Con-
sequently, improving the attractiveness of
monitoring and bait stations has been the
primary goal. Cornelius et al. (2009) found
that the diffusion of an aqueous solution
into the soil underneath monitoring stations
signifi cantly decreased the length of time
required for termites to infest stations. R.
fl avipes , Reticulitermes tibialis and Reticuli-
termes virginicus were attracted to CO 2
concentrations between 5 and 50 mmol/mol
and termites foraged signifi cantly more in
CO 2 generating bait stations at treatment
fence posts than in bait stations at the
control fence posts (Bernklau et al. , 2005).
The fi ndings were corroborated by
Broadbent et al. (2006).
Another area of continued research is the
development of suitable bait matrices. Wang
and Henderson (2012) report that cob, a
waste product of the food and biofuel
industry, is as effi cient as wood and card-
board as a termite bait matrix. The addition
of a polymer binder to a refi ned cellulose
matrix improves consumption of baits with
novifl umuron compared with a textured
cellulose matrix (Hamm et al. , 2013).
The active ingredient in the bait matrix is
critical to the success of baits. Compounds
such as the CSIs that are slow acting, non-
repellent and dose independent are ideal
candidates. In area-wide baiting studies,
baits containing 0.1% difl ubenzuron had no
noticeable effect on C. formosanus and R.
fl avipes populations (Osbrink et al. , 2011).
Chlofl uazuron (0.25%) and hexafl umuron
(0.5%) signifi cantly reduced termite popu-
lations in about 3 and 2 years, respectively.
Lufenuron baits effectively eliminated
colonies of Reticulitermes hesperus with
baited colonies devoid of foragers within an
average of 71 days (Haverty et al., 2010). All
wood consumption ceased in baited col-
onies by week 16. The authors recommend

Baits and baiting technology

One of the most important limiting factors
affecting the inclusion of baits into termite
treatment strategies by PMPs is the add-
itional costs, especially the labour, when
compared with conventional soil treatments
(Su, 2011). Improvements in the design of
baits and their servicing help reduce the
cost to PMPs and the possibility that ter-
mites might abandon the station before the
colony is eliminated. Eger et al. (2012)
report that a refi ned cellulose matrix plus
novifl umuron provided colony elimination
and greatly reduced labour costs by