TURFGRASS,
LANDSCAPE
URBAN IPM
RESEARCH
SUMMARY
A2'1246
Series?'126
CooPerativeExtension
Agri cultural ExPeriment Station
The UniversitY of Arizona, Tucson
U.S.Department of Agriculture
Influenceof pH 11Wateron TermiticideDegradationin
Arizona
Paul B. Baker. Ph.D.
Specialist irt Entomologt
Department of Entomologt
Universitv of Arizona
Ab'tstract
Termites continue to be Arizona's number one urban pest. Factors that
inJluence the persistence of termiticides are constantly under
investigation. High pH has been identified as a potential concern for
persistence in termiticides. I studied the inJluence of pH I I water on
five termiticides applied to commercial ABC fill I0 months posttreatment. In general, the addition of pH I I water had little influence
on termiticide persistence under Arizona conditions. Initially plots
treated with Ph I I water had higher residues than those that did not
receive the treated water; over time these diferences diminished.
The use of termiticides to halt the i:rvasion of termites is well documented(Kard, et al 1989, Gold et al, 1996
aud Su, et al 1993). However, terraites continue to be Arizona's number one urban pest (Potter, M.F. 1997).
Factors that inlluence the persistenceof termiticides have been the subject of rnany studies by both
researchersand registrants. A potentially important factor is the influence of high pH water on the
degradationof termiticides. The pH of water in contact with cementmay vary from 9 to 12 (F.M. Lea, 197 I )
depending on the cemen! lime and calcium carbonateproportions. I snrdied the inJluence of pH 11 water on
five termiticides applied to cornmercialABC fill for l0 months post-treatrnent.The results of the study are
reported here.
Using a randomized corrplete block desigr, I testedthe following termiticides: permethrin @ragnet @0.5%
A.I.), fenvalerate(Tribute @0.5% A.I.), chlorpyrifos (Dursban TC @ L.0% A.I.), bifentbrin (Biflex @
0.06% A.L), cyperrrethrin (Prevail @0.25% A.I.) and a contol. We constnrcted 36 wood frames, each
5.08cm x 5.08cm x 15.24 hig\ using 5.08cm x l5.24cmlumber. The frames were placed on the ground and
cornrnercialABC fiU (pH 8.3, EC>15, sand17%o,silt 72To,clay ll%) was placed in all 36 frames. All
termiticides were mixed as per manufactuter's recornmendationsand applied to six plots each. Spray
mixtures were applied at I gallou/l0 square feet. All teatrnents were covered with 5.08cm x 5.08cm x l.3cm
plywood covers.A concrete block was placed on top to hold the cover in place. Four hours later we applied
pH l1 water to three of the six replications of each termiticide teatnent and contol plots. Sodiumhydroxide
was added to water in 0.1 gram iacrementsr:ntil the water reachedpH 1 I using Litnus paper as an indicator.
Covers were removea and t.g liters of pH 11 water was appiied to all plots, then plywood covers were
replaced. After 20 minutes, using a stainlesssteel sampler with a clear plastic sleeve, I took saryles to a
depth of approxirnately7.6cm" Sanples were taken at 0, l, 2,4, 16,32 and 302 days post-teabent. Soil
sampleswere frozen and shippedto FMC's Agricultural Products Group in Princeton, NJ for analysis.
Saryles were processsdssselrling to APG Test Methods 256,257 and 376. All sarnples v/ere removed from
their plastic holders, air dried on aluminum foil at room terrperature for 24 hor:rs, then gently crushed to pass
through a 2 mmsieve, extractedin triplicate with 50/50 (v/v) hexane/acetone,and anallzed by gas
cbromatographywith electron caPturedetection.
br general, the addition of pH 1l water had little inJlueqce on termiticide degradation (Figures l-5). Analysis
of variance and Drmcan's Multiple Range test revealed no differences benveen pH 1 I teated soil and
controls (P>.05) except in the caseof Dragnet (Fig 3) which did show significant statistical differences
(P<.05) berweentreated soil and confrols lnitially plots teated with pH I I water had slightly higher
concentations than those that did not receive the teated water. Over time these differences diminished. The
similar to those found in a 5-year termiticide
residues detectedat 0 to32 days post-teaunent were
I study (Baker, unpublished data)' Biflex (Fig' I ) and
degradation study that *as locatid adjacent to the pH I
the duration of the 1O-monthstudy' Prevail (Fig'
Dragnet (Fig. 3) sbowed rhe greatestiersistence throughout
302-day sampling date'
5) exhibited lossesof over 78% io 94o/orespectivelyby the
il;an(Fig.
ttil
initial concentation by the
its
maintained
but
sody
the
Fenvalerate(Fig. a) displayed variability tbroughout
last sanpling date.
within l0 months under Arizona conditions'
The data implies that some termrticides degrade rapidly
had little or no inJluenceon that degradation'
*uttt
pif
i
t
However, ow results suggestthat the addition of
ReferencesCited
G o l d , R . E . , H . N . H o w e l l , J r . , B . M . P a w s o n , M . S . W r i g h t a n d J . c . L u t z . 1 9 9 6 ' P e r s i s t e n c e a n d b irn
oavailabilitt
from five soii types and locations
of termiticides to subterraneantermites (Isoptera: Rhrnotermrtidae)
-363'
Texas. Sociobiology28(3): 337
of soil termiticidesfor control of subterrrttt'rrrr
Kard, B.M., J.K. Mauldin and S.C.Jones. 1989. Evaluation
-297'
(3)
28
5
:
termites(Isoptera).Sociobiology | 5
(66 edition) 1986-1987.ChemicalPublislringt "
Lea, F.M. 1971. CRC Handbookof Chemistry and Physics
Inc. New Yorh 177-185.
Cbapter6' Tennites' Mallis Handbook and
Potrer,M.F. 197?.Handbook of PestControl (86 edition)
Technical lpining Co.
Study - Tucson,AZ 1997
800
E
CL
;
g
=
6
400
ItrlControl
l
l r P h1 1
200
andP.M.Ban. 1993.Barrierefficacyof pyrethroidandorganophosphate
Sq N.-Y.,R.H. Schefaahn,
terrrites (Isoptera:Rhinotermitidae).J- Econ.Entomol' 86(3) 772-776'
i#froUtio* againstsubterranean
Fig.2. Prevail,pH 11 Study- Tucson,AZ 1997
1000
E
I
800
--.---l
locontrotll
600
G
o
r
l-i
r p h1 1 j i
400
200
0
2
4
1
6
3
1
3
0
2
Days
Fig.3. Dragnet,pH 11 Study-Tucson, AZ1997
1000
?
800
g
600
trControl
rph 11
o
3 4oo
o zoo
G
0
2
4
1
Days
6
3
1
3
0
2
Fig.4.Fenvalerate
, ph 11 Study'Tucson,lZ1997
1000
800
o
600
(E
q)
IE
o
lt
400
200
n
o
1
2
4
16
31
Days
F
Fig.5. Dursban,ph 11 Study'Tucson,A21997
1000
F
g
e
G
800
600
o
400
o
200
L
0
p-Controt
[rpn rr