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Evaluation of a Localized Treatment Technique Using Three Ready-to-Use Products Against the Drywood Termite Incisitermes snyderi (Kalotermitidae) in Naturally Infested Lumber

Authors:
Robert Hickman at BASF
Robert Hickman
Brian T Forschler at University of Georgia
Brian T Forschler
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Abstract

Twenty-one boards infested with drywood termites were examined for activity using a Termatrac“ motion detector. Termite galleries were identified using a Resistograph drill and treated with one of three ready-to-use (RTU) products. Results indicated that the Termatrac was excellent at locating termite activity but provided 9.5% false negatives. The Resistograph located termite galleries with an average of 4.6 ± 2.7 holes drilled to find at least one gallery in a board. Treatments included three formulations and two active ingredients; a foam (imidacloprid), a dry (fipronil) and an experimental formulation in a pressurized can (fipronil). All treatments provided evidence for a reduction in mean termite populations per board compared to the control. Two treatments provided evidence of elimination of infestation but no formulation eliminated infestations in every board that was treated. The concept of local treatment for drywood termite control is discussed relative to our results.
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Evaluation of a Localized Treatment Technique Using Three Ready-to-Use Products Against the Drywood Termite Incisitermes snyderi (Kalotermitidae) in Naturally Infested Lumb
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... Subsurface injections employing the drilland-treat method -locating galleries by drilling into the lumber and applying a pesticide through the drill-hole into the gallery -using dust formulations of Paris green (sodium fl usilicate) and calcium arsenic (Kali-dust) were the mainstay of drywood termite control efforts in the early 20th century (Light et al., 1930; (Potter, 2011). Over the decades, published effi cacy testing on active ingredients includes dozens of insecticides (Smith, 1930;Mallis, 1945;Snyder, 1950;Ebeling and Wagner, 1959a,b;Ebeling, 1975;Scheffrahn et al., 1979;Rust and Scheffrahn, 1982;Moein and Farrag, 1997;Scheffrahn et al., 1979Scheffrahn et al., , 1997aThoms, 2000;Ferster et al., 2001;Lewis and Power, 2004;Lewis et al., 2005;Woodrow et al., 2006;Woodrow and Grace, 2007;Lewis, 2009b;Lewis and Rust, 2009;Rust and Venturina, 2009;Lewis et al., 2011;Hickman and Forschler, 2012). Remedial interventions that involve insecticidal foam formu lations applied using subsurface injection have been examined in conjunction with detection equipment (Lewis and Rust, 2009;Rust and Venturina, 2009;Lewis et al., 2011;Hickman and Forschler, 2012), although the practice of foaming wall voids as a preventative intervention strategy needs additional research. ...
... Over the decades, published effi cacy testing on active ingredients includes dozens of insecticides (Smith, 1930;Mallis, 1945;Snyder, 1950;Ebeling and Wagner, 1959a,b;Ebeling, 1975;Scheffrahn et al., 1979;Rust and Scheffrahn, 1982;Moein and Farrag, 1997;Scheffrahn et al., 1979Scheffrahn et al., , 1997aThoms, 2000;Ferster et al., 2001;Lewis and Power, 2004;Lewis et al., 2005;Woodrow et al., 2006;Woodrow and Grace, 2007;Lewis, 2009b;Lewis and Rust, 2009;Rust and Venturina, 2009;Lewis et al., 2011;Hickman and Forschler, 2012). Remedial interventions that involve insecticidal foam formu lations applied using subsurface injection have been examined in conjunction with detection equipment (Lewis and Rust, 2009;Rust and Venturina, 2009;Lewis et al., 2011;Hickman and Forschler, 2012), although the practice of foaming wall voids as a preventative intervention strategy needs additional research. At least one essential oil (containing D-limonene) is commercially available for local, remedial treatments (Lewis and Rust, 2009;Rust and Venturina, 2009;. ...
... Arthropod response to essential oils has, however, been highly variable within and between pest species (Cornelius et al., 1997). Collectively, reports on product effi cacy in controlling infestations are highly variable, and depend on active ingredient, formulation (liquid versus dust versus foam), fi nding galleries and feeding chambers (Ebeling, 1975), application technique (topical or injection) and species of drywood termite Su and Scheffrahn, 1990;Scheffrahn et al., 1997a;Su and Scheffrahn, 2000;Lewis, 2003;Woodrow and Grace, 2007;Woodrow et al., 2006;Rust and Venturina, 2009;Potter, 2011, Hickman andForschler, 2012). Describing the mode-ofaction for the products tested and/or used for drywood termite wood injection treatments is beyond the scope of this chapter and the reader is referred to the literature cited in this chapter. ...
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... Moreover, the architecture of a C. brevis gallery system may impede the complete coverage of the gallery system where termites are active when using foam or liquid formulations. This could be due to back pressure while applying liquid insecticides because of dead-end galleries and the narrow interconnecting galleries that pellets or termites can block [8,9]. Overcoming these issues would take considerable time, require numerous drill holes in termite-infested wood, and insecticide applications spread out over several months. ...
... The gallery system of C. brevis is composed of enormous chambers connected by narrow passageways. Loosely packed fecal pellets or termites can easily block these tiny passageways; therefore, the architecture of the drywood termite gallery system creates a blockage that may prevent the complete distribution of insecticides used for spot treatments [8,9]. Two separate experiments were carried out to ascertain the pyrethrin-containing aerosol penetration through C. brevis fecal pellets. ...
Potential of Gas-Propelled Aerosol Containing Synergized Pyrethrins for Localized Treatment of Cryptotermes brevis (Kalotermitidae: Blattodea)
Article
Full-text available
  • Jun 2023
The possibility of synergized pyrethrin-containing aerosol as a choice for spot-treating C. brevis in Australia was investigated in laboratory tests. Topical toxicity tests, where C. brevis pseudergates were subjected to multiple doses of pyrethrin mist insecticide, showed the concentration-dependent death of termites with a median lethal dose (LD50) of 193.16 μg. Residual toxicity tests, where the termites were exposed to wood surfaces treated with pyrethrin-containing aerosol, showed rapid mortality in short and continuous exposures. Less than 20% of the termites survived even when the termites were exposed to a treated wood surface for a minute. All the termites died within 1–5 h in continuous exposure tests, depending on the age of the treated surface. In repellency tests, the termites tended to visit treated surfaces, causing an overall lower survival of the termites. The synergized pyrethrin-containing aerosol remained insufficiently volatile to produce the complete mortality of the termites even after 196 h when there was no contact with a treated surface. The number of termites that survived following the application of the synergized aerosol through a simulated wood gallery or silicon tubing with fecal pellets was also negligible, demonstrating the ability of the aerosol to penetrate through pellets and ultimately resulting in a distribution that is ideal for treatment in the termite galleries.
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... abrupt loss of resistance) are used to infer changes in the material, in our case the presence of voids in the wood. Among other applications, resistance drilling has been used to assess termite damage in wood (Hickman & Forschler, 2012), radial changes in wood density in pedunculate oak stands (Tomczak et al., 2022) and climateassociated variation in wood in Eucalyptus nitens M. plantations (Rocha Sepúlveda, 2023). Trees across all sites were drilled at breast height (at 130 cm above ground) across the longest diameter from end to end (Fig. S1). ...
Shifts in internal stem damage along a tropical precipitation gradient and implications for forest biomass estimation
Article
Full-text available
Woody biomass is a large carbon store in terrestrial ecosystems. In calculating biomass, tree stems are assumed to be solid structures. However, decomposer agents such as microbes and insects target stem heartwood, causing internal wood decay which is poorly quantified. We investigated internal stem damage across five sites in tropical Australia along a precipitation gradient. We estimated the amount of internal aboveground biomass damaged in living trees and measured four potential stem damage predictors: wood density, stem diameter, annual precipitation, and termite pressure (measured as termite damage in downed deadwood). Stem damage increased with increasing diameter, wood density, and termite pressure and decreased with increasing precipitation. High wood density stems sustained less damage in wet sites and more damage in dry sites, likely a result of shifting decomposer communities and their differing responses to changes in tree species and wood traits across sites. Incorporating stem damage reduced aboveground biomass estimates by > 30% in Australian savannas, compared to only 3% in rainforests. Accurate estimates of carbon storage across woody plant communities are critical for understanding the global carbon budget. Future biomass estimates should consider stem damage in concert with the effects of changes in decomposer communities and abiotic conditions.
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... 흰개미의 활동을 탐지하기 위해 마이크로파 측정기, 모니터링 스테이션 등 다양한 비파괴 모니터링 방법이 동 원되고 있다 (Kim et al., 2010;Chung et al., 2015). 이 중 (Hickman and Forschler, 2012;Barway et al., 2015;Taravati, 2018 (Park, 1996;Jeong et al., 2018). ...
Changes in the Detection Performance of Termatrac T3i as a Reticulitermes Speratus Detection Device According to the Wood(Species and Moisture Content) and Detection(Depth and Direction) Condition
Article
  • Oct 2022
This study confirmed the detection performance and applicability of microwave devices used to detect subterranean termites inside the wood. The detection performance of Termatrac T3i decreased as the specific gravity and moisture content increased due to the anisotropy and wave absorption characteristics of wood. Additionally, Termatrac T3i was able to detect termites within a radius of 50 mm and a maximum depth of 50 mm based on the measurement point due to the strong straightness of the 2.4 GHz microwave. These results suggest that the measurement interval and depth o f Termatrac T3i sho uld be set within 100 mm and 50 mm to determine the termite activity inside the pine wood member. Additionally, the applicability according to the detection performance of Termatrac T3i was investigated. The results confirmed the damage pattern in which Reticulitermes speratus preferentially attacked the sapwood of the wood member, and that the average sapwood width of the pine tree used as the wood member of the wooden structure was approximately 60-70 mm. Therefore, Termatrac T3i, which has been confirmed to be able to measure termite activity up to 50 mm deep in a straight line for pine trees, is considered to be applicable to the detection of activity of R. speratus , which prefers sapwood.
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... (3) based on the acoustic signal, Evans [15] tested the performance of microwave acoustic (Termatrac TM , Australia) to detect termite (Coptotermes lacteus and Nasutitermes exitiosus) and obtained an accuracy of 90% in the field. With a similar device, Hickman and Forschler [75] reported that the performance of Termatrac TM achieved an accuracy of 90.5% for detecting a drywood termite Incitermes snyderi. Lewis et al. [18] also conducted testing of a acoustic emission device (insect detector Ò , DowAgrosciences) to detect termites Incisitermes minor, which displayed an accuracy of 89.45%. ...
Development of termite detection system based on acoustic and temperature signals
Article
  • Aug 2019
  • MEASUREMENT
The subterranean termite, belonging to the genus Coptotermes, is the pest that causes maximum destruction in wooden structures, forest trees and crops. Owing to its aggressiveness and hidden existence, it is difficult to visually determine whether a termite infestation is active and damage is occurring. Consequently, the development of a termite detection system as a critical component of termite pest control systems is necessary. A novel termite detection system was developed based on acoustic and temperature signals. The system has two capabilities: it can detect the presence of termites and estimate the population size. In this study, a support vector classification (SVc) and artificial neural network (ANN) algorithm were applied to recognize the termites’ signals. After optimizing various input types, kernel functions and model parameters, a robust model was successfully constructed with a specific capability, i.e., a SVc model for detecting termites and ANN model for estimating the termite population. Based on the performance assessment, the proposed termite detection system can detect the presence of termites with an accuracy of 93.83% and estimate their population with a root mean square error (RMSE) of 123.828. The results of our study indicated that the embedded models in the proposed termite detection system successfully proved the feasibility of detecting the presence of termites and simultaneously estimating the size of their population.
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... In manner similar to dusts, non-repellent termiticides such as fipronil and imidacloprid may be applied as liquid or foam directly into termite workings (178). Another method of control for subterranean termites is with fumigants, more widely used in the USA (179), while in Australia Dazomet® (3,5-dimethyl-1,3,5-thiadiazinane-2-thione) was effective against termites infesting eucalypt poles (180). ...
Termites and Timber
Chapter
  • Jun 2014
The management of termite risk for the protection of timber structures mainly from subterranean termites, are discussed. Inedible wood may be produced from naturally durable timber, impregnation using extractives from naturally durable wood, wood preservatives such as preservative oils, copper-based preservatives, pyrethroids and other organic insecticides, modified wood and preserved wood composites. These measures should be used in conjunction with a whole-of-structure approach that protects buildings using barriers such as graded particles that termites cannot penetrate, resistant sheet materials, or soil treatments. Traditional and electronic detection methods are available for detecting termite activity in a structure, which then allows additional control methods such as baiting and dusting to be introduced. An understanding of the termite hazard and their habits will allow for improved building design and maintenance regimes that will mitigate the risk of termite attack.
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Detection and monitoring techniques of termites in buildings: A review
Article
  • Aug 2024
  • INT BIODETER BIODEGR
Termites are significant pests in many regions of the world, where they attack cellulose-based material in buildings, trees, and crops. The most significant economic losses occur to timber in structures, and a great deal of effort and money is spent to prevent damage to homes and public buildings. Termites may attack wood anywhere in a building, from below soil to the highest point on the roof. Detection of termites is often challenging due to the cryptic nature of termites, the complexity of the structure, the location of damage or termites in the structure, and available techniques. Several methods have been employed to detect and monitor the presence of termites in buildings, from simple visual searches to technology-based or technology-assisted approaches that vary in their invasiveness and destructiveness. This review examines the various techniques used to detect drywood and subterranean termites, explains the underlying termite biology connected with each detection method, and considers the benefits and drawbacks of each technique discussed. This will hopefully help professional pest inspectors and property owners select suitable termite detection methods. This review also highlights the need for continued research to develop and evaluate detection strategies and tools that may be utilized before implementing any termite control measures.
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Evaluation of Low-Energy Microwaves Technology (Termatrac) for Detecting Western Drywood Termite in a Simulated Drywall System
Article
  • Mar 2018
Detecting drywood termites in structures is very challenging. Microwaves technology (Termatrac T3i) is a nondestructive method for detecting drywood termites in structures. Termatrac device and its mobile application provide a bar as well as a line graph when detecting insect movements, but interpreting these graphs is very subjective. In this paper, Termatrac's output signal is quantified using a new method to study the effect of wall layers, wood type, and termite density on signal strength measured as area under curve in a simulated drywall system in laboratory. Two experiments were conducted on Termatrac T3i at its maximum sensitivity (Gain: 10). In experiment I, HEXBUG Nano was used as a source of movement/vibration and two wood types were used in which the wall layers significantly predicted signal strength, but wood type did not. In experiment II, two different densities of live western drywood termites, Incisitermes minor (Hagen) (Isoptera: Kalotermitidae), were used to study the effect of termite density on signal strength. Interestingly, termite density did not significantly predict signal strength. The maximum reliable wood depth for detecting termites was 5 cm. Microwaves produced by Termatrac also showed good penetration into drywall and produced detectable signals even on a single drywood termite which confirms manufacturer's claim. Suggestions on using and improving microwaves technology for detecting termites is provided which can potentially be applied to other types of insects and noninsect animals.
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The Effect of Foraging Tunnel Treatment with Termidor® DRY on Reticulitermes flavipes (Isoptera: Rhinotermitidae)
Article
  • Jan 2013
  • J Agr Urban Entomol
The efficacy of a dry, ready-to-use (RTU) termiticide formulation of fipronil was evaluated against termite foraging activity and survival by injection into foraging tunnels of Reticulitermes flavipes (Kollar) (Isoptera: Rhinotermitidae) in a laboratory study. Groups of workers (older than 3rd instars) were placed in bioassay units consisting of a group site and a feeding site connected by termite tunnel(s) within a soil-filled Tygon tube. Two treatments (0.15 and 0.30 mg a.i. fipronil per treatment) were conducted by injecting the doses into a foraging tunnel near the feeding site. Bioassay units were monitored for termite movement utilizing Termatrac® T3i until no movement was detected. Termite movement ceased at day 5 and 7 for the 0.30 and 0.15 mg dose treatments, respectively. Dissection of the bioassay units confirmed 100% mortality at the days when both visual observations and Termatrac T3i indicated no termite movement. Termites in the treated units constructed significantly fewer tunnels post-treatment compared to control termites. Our results provided strong evidence for the efficacy of the dry RTU fipronil formulation against R. flavipes activity at the group level when a single tunnel was treated.
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Surface and subsurface sensor performance in acoustically detecting the western drywood termite in naturally infested boards
Article
Full-text available
  • Jan 2005
Drywood termites attack wood structures and are serious pests on most continents (Su and Scheffrahn 2000). Around the world, the family Kaloterm-itidae contains 21 genera and several hun-dred species of economic importance (Pearce 1997, Su and Scheffrahn 2000). In North America, there are 14 species of drywood termites of which 5 have eco-nomic importance (Su and Scheffrahn 1990). Each year the damage caused by drywood termites is considerable and rep-resents > 20 percent of the several billion dollars spent on termite detection, con-trol, and repairs of damage in the United States (Lewis and Haverty 1996; Su and Scheffrahn 1990, 2000). Before drywood termites can be con-trolled, they must first be detected. The primary inspection tools are visual FOREST PRODUCTS JOURNAL Vol. 54, No. 6 57 The authors are, respectively, Extension Specialist, and Abstract
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Assessing efficacy of Termatrac™; a new microwave based technology for non-destructive detection of termites
Article
Full-text available
  • Jan 2002
Termites are difficult to detect reliably and many detection methodsare destructive to property or disturbing to the termites (which mayinterfere with remedial treatment). The reliability of Termatrac™ a newdevice designed to detect termites in a nondestructive and non-disturbing manner, based on novel microwave technology, was testedin the field by assessing termite presence as indicated by the device in119 aggregation stations. There were 90% correct assessments: 56.5%of aggregation stations were correctly assessed as having termites and33.5% were correctly assessed as not having termites. The incorrectassessments were: 1.5% assessed as having termites when there werenone (due to the presence of other insects) and 8.5% as not havingtermites when they were present (due to high moisture levels inaggregation stations, i.e. absorption of the microwaves). Ants could bedistinguished from termites as they produced significantly differentsignals (as displayed on the LCD screen) from termites. With appropri-ate training and experience in interpreting termite (vs. other insect)signals, Termatrac™ should increase termite detection with decreasedeffort and disturbance in many situations.
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Expansive Gallery Systems of One-piece Termites (Isoptera: Kalotermitidae)
Article
Full-text available
  • Jan 2009
Drywood termites (Family Kalotermitidae) have been termed "one-piece" termites to reflect the fact that they nest within their food source. We dis-sected a large number of hardwood shipping pallets infested by Cryptotermes brevis (Walker), and mapped the distribution of individual termite colonies (i.e., interconnected gallery systems) within individual boards, and within the pallet as a whole. The number of distinct colonies within a single pallet ranged from one to eight. Although some colonies occupied a single board, we also found multiple colonies within single boards, and single colonies tunneling through the junctions between boards and occupying virtually the entire shipping pallet. Although designation of drywood termites as one-piece type termites is a useful ecological distinction, these cryptic insects may have extensive gallery systems encompassing multiple adjacent food sources.
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Evaluation of Six Techniques for Control of the Western Drywood Termite (Isoptera: Kalotermitidae) in Structures
Article
Full-text available
  • Jul 1996
  • J ECON ENTOMOL
Chemical and nonchemical methods for control of western drywood termites, Incisitermes minor (Hagen), were evaluated under conditions that simulated infestations in structures. The efficacy of excessive heat or cold, electrocution, microwaves, and 2 fumigants was evaluated. Termite mortality in artificially infested boards was 100% at 3 d after treatment for both fumigant gases. Heating the whole-structure or spot-applications using microwaves resulted in 96 and 90% mortality, respectively, 3 d after treatment. Mortality levels 4 wk after treatment increased to 98% for heat and 92% for microwaves. Spot-applications of liquid nitrogen at 381.8 kg/m3 achieved 100% mortality 3 d after treatment. However, for 122.7 and 57.3 kg/m3, mortality levels 4 wk after treatment were 99 and 87%, respectively. Mortality by spot-applications of electricity was 44% 3 d after treatment in the 1st test. Four weeks after treatment drywood termite mortality increased to 81%. In a 2nd electrocution test, using spot application techniques infrequently used in structures, mortality levels increased to 93% at 3 d and 99% at 4 wk after treatment. The distribution of termite survivors within the test building and test boards varied for some treatment techniques. For naturally infested boards, both fumigants exceeded 99% mortality. Use of heat and microwaves resulted in 100 and 99% mortality levels, respectively, 4 wk after treatment. Applications of liquid nitrogen resulted in mortality ≥99.8% at 381.8 and 122.7 kg/m3; however, mortality for 57.3 kg/m3 was significantly lower (74%). Mortality levels from electrocution were 89 and 95% 4 wk after treatment, respectively, in the 2 tests. Damage to test boards and the test building did occur. Six test boards were scorched during microwave treatment, 80% of test boards were damaged during electrocution, and visible signs of damage to the test building were noted for whole-structure heating. This study provides information for evaluation of the relative efficacy of fumigation and nonchernical alternatives for the control of drywood termite infestations in structures.
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Termites: Evolution, Sociality, Symbioses, Ecology
Book
  • Jan 2000
The book is a new compendium in which leading termite scientists review the advances of the last 30 years in our understanding of phylogeny, fossil records, relationships with cockroaches, social evolution, nesting, behaviour, mutualisms with archaea, protists, bacteria and fungi, nutrition, energy metabolism,population and community ecology, soil conditioning, greenhouse gas production and pest status.
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Use of an Acoustic Emissions Detector and Intragallery Injection of Spinosad by Pest Control Operators for Remedial Control of Drywood Termites (Isoptera: Kalotermitidae)
Article
  • Mar 2000
During 1997, four pest control companies in Florida (FL) participated in experimental use permit field trials to evaluate spinosad (NAF-85) for control of drywood termites (DWT). Forty-four DWT infestations of Incisitermes snyderi (Light) and Cryptotermes brevis (Walker) in 37 structures in FL were delineated using an acoustic emissions detector (AED). These infestations were injected with a 0.5% spinosad suspension concentrate formulation using a hand-held injector. The majority of these infestations were interior (68%) and were completely accessible (86%). The visible signs most frequently associated With DWT infestations were pellets (93% of infestations). A mean of 10 holes were drilled and 4.3 holes were injected with a total mean of 60.7 ml spinosad per infestation. At a mean of 44 dans post-treatment, the overall reduction in acoustic emission (AE) counts/30 sec was 94%. AE activity was reduced by ≥90% at 89% (n = 40) of the infestations and was completely eliminated at 61% (n = 27) of the infestations. The mean time to monitor a DWT infestation using the AED was 23.4 min for the 1(st) visit and 6.3 min for the 2(nd) visit. The mean time to drill, inject NAF-85, and plug drill holes was 13.7 min per infestation. The mean total time per trial site was 58.6 min for the 1(st) visit and 13.1 min for the 2(nd) visit. Results demonstrated the combination of the AED, spinosad and injector provided efficient and effective control of localized, accessible DWT infestations.
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Global Patterns of Termite Diversity
Article
  • Jan 2000
What is known of termite global diversity patterns is reviewed at a number of spatial scales (from Neotropics > Oriental tropics. This contradicts the predictions of energy-diversity theory. Both of these gradients can be described as “diversity anomalies”. Multivariate analyses of generic WORLDMAP data are reviewed showing that the latitudinal and longitudinal diversity anomalies are due to the differential distribution of termite clades in different biogeographical regions, rather than a uniform difference across all clades between regions with different diversities. Different clades may, therefore, have evolved in different areas due to particular idiosyncratic events across geological time, and then may not have dispersed significantly from their original biogeographical regions. Indeed, the limited data that are available suggest that termites are generally poor dispersers across geographical barriers. The present, admittedly incomplete data, suggest that the families of termites may have evolved on Pangaea prior to the break-up of that supercontinent, and that the major clades of the Termitidae may have evolved subsequently on the separate pieces. The characteristics of the termite fauna of the different regions are discussed, as well as the distribution of genera within the putative clades. Termites appear to represent a very good example of a group whose biology and ecology are strongly influenced by history. Some possible consequences of these historical constraints on ecological processes are briefly discussed.
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Laboratory and Field Evaluations of Selected Chemical Treatments for Control of Drywood Termites (Isoptera: Kalotermitidae)
Article
  • Apr 1997
  • J ECON ENTOMOL
A 1-m board bioassay was used to assess the efficacy of spinosad, disodium octaborate tetrahydrate (DOT), calcium arsenate, and chlorpyrifos on the mortality and fecal pellet production of 2 drywood termite species, Incisitermes snyderi (Light) and Cryptotermes brevis (Walker), under unforced exposure and simulated field conditions. Spinosad suspension concentrate at 2,300 or 5,000 ppm, 35% calcium arsenate, and chlorpyrifos aerosol at 5,000 ppm were more toxic and reduced pellet production compared with DOT treatments at 4 wk. Of DOT treatments, only 98% dust caused higher mortality than controls at 8 wk. Spinosad suspension concentrate and chlorpyrifos had an effect on termite location in bioassay boards. Acoustic emissions activity of 55 C. brevis infestations in 2 buildings was determined before intragallery injection of liquids and dusts tested above, with the exception of arsenate dust, and surface application of 10% DOT. After treatment, acoustic emission activity was recorded for each infestation at 1, 2, 3, 5, 8, and 12 mo. At 4 mo, one building was fumigated with sulfuryl fluoride. Posttreatment readings taken 3 mo or earlier for infestations treated with spinosad suspension concentrate, chlorpyrifos, and DOT surface showed reductions in acoustic emission activity. Only spinosad SC treatment yielded significant acoustic emission reductions at 5 mo or later. Results suggest that chemical toxicity, formulation, and application method, as well as drywood termite behavior and gallery system architecture, influenced the performance of local chemical treatments. Sulfuryl fluoride fumigation resulted in cessation of acoustic emission activity in all colonies monitored in the fumigated building.
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