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Is termite body size correlated with colony vigor?
1995 - IRG/WP 95-10130
Folk wisdom among termite researchers holds that the average body size (mass) of workers in a subterranean termite colony (Rhinotermitidae) is associated with the age and/or vigor of the colony. In particular, extremely large individuals are frequently thought to indicate a very old, or senescent, termite colony. However, there are very little data to support this assumption. It is also difficult to understand why subterranean termite colonies of advanced age, with a continuing food supply and supplementary reproductives presumably active in egg production, should be prone to senescence. We present data from 16 years of observations on a Coptotermes formosanus Shiraki field colony demonstrating a negative proportional relationship between average individual worker mass and estimated size of the colony foraging population. These results do not explain the phenomenon of senescence, but do suggest that decline in colony population size may be predicted from a measured increase in the average individual mass of workers sampled over a given period of time.
J K Grace, R T Yamamoto, M Tamashiro


Estimating the size of subterranean termite colonies by a release-recapture technique
1980 - IRG/WP 1112
The technique is described and the results of an exploratory field trial are presented. The colony size estimate from weekly termite collections varied considerably, but nevertheless permitted assigning termites at three locations to three categories of greatly different colony size. The sizes of the three estimates were much greater than anticipated and included a multimillion termite complex of interconnected colonies. The results indicate that the technique can be developed for estimating the size of termite colonies involved in evaluations of insecticidal termite bait treatments.
G R Esenther


Survey of termites in forests of Punjab: Pakistan
2010 - IRG/WP 10-10726
Termites were surveyed in seven forests in the Punjab (Bhagat, Kamalia, Chichawatni, Changa Manga, Jallo Forest park, Daphar and Attock) during 2008. Twelve termite species were observed from soil, dead logs, live wood and living trees. Host trees were also identified. The percentage of infested plants in Kamalia, Bhagat, Chichawatni, Changa Manga, Jallo Forest park, Daphar and Attock forests were 22.50%, 20.00%, 19.60%, 15.45%, 10.00%, 20.00% and 12.10% respectively. Examination of dead wood in seven forests showed that an average of three quarters of wood sampled were attacked by termites. The number of termites per unit volume of dead wood were also determined in these forests and it was almost similar (0.4 per cm3). The size of colony was correlated with the volume of dead wood and it ranged from 26-2,784 termites, the soldier caste ranged from 2.1% to 20.00% of the total population of the termite colony. In all these forests, 20% of the dead wooden logs and branches showed signs of subterranean termite (‘termite’).
F Manzoor, B M Ahmed Shiday, S Malik, A Rahim, B Habibpour, J R J French


Leaching of components from water-borne paints and fungitoxic effects
1995 - IRG/WP 95-20062
Water-borne model paints, acrylics and alkyd emulsion paints, of known composition were leached according to a procedure modified in accordance with ASTM 6271.1. The effectiveness of fungicidal compounds in the painted specimens before and after leaching was evaluated with a biotest in which Penicillium brevicompactum was used as a test fungus. The leaching of the fungicide Troysan Polyphase according to the biotest varied to a high extent depending on differences in paint composition. Fungicide efficiency in relation to paint formulation and fungicide mobility in a paint film is briefly discussed.
J Bjurman


Factors affecting leaching of preservatives in practice
1978 - IRG/WP 3113
At the 7th Meeting of the IRG in Poland in May 1975, the findings of collaborative laboratory leaching techniques were discussed, and the dangers inherent in using such results to predict the behaviour of preservative-treated components in service were emphasised. In order to improve our understanding of the factors governing leaching of preservatives in practice, and to identify areas where further research is required, it was agreed that a literature review should be prepared. This is presented below. Some points may be made regarding its format and content. First, the review shows that a large number of factors are of importance, including the properties of the wood, the leach water, the preservative and method of application and the nature of the environment to which the product is exposed. In many situations these factors interact and it is clearly impossible within the scope of this short paper to discuss all aspects of the problem in detail. However, the compilation of references will give ready access to the literature on particular topics. For ease of collation, the findings are discussed under a number of different headings. Secondly, less than one-third of the references cited deal with the results of service or field trials, while the others describe laboratory experiments designed to provide comparative data. The reservations expressed above concerning such small-scale experiments must be borne in mind when considering the validity of these findings. The information available on this topic up till 1964 was comprehensively reviewed by Wallace who identified and commented upon many of the factors discussed below. Her paper contained discussion on the performance of individual preservatives and on the mechanism of their fixation within the wood. These topics will not be considered here in any detail except insofar as they reflect general trends.
R Cockcroft, R A Laidlaw


Spore germination of Gloeophyllum trabeum on wood is related to the mass of the wood sample
1978 - IRG/WP 2118
E L Schmidt, D W French


Differences in feeding activity among colonies of Formosan subterranean termite Coptotermes formosanus Shiraki
1983 - IRG/WP 1202
Feeding activities of 7 colonies of the Formosan subterranean termite, Coptotermes formosanus Shiraki, were examined. Wood-consumption rates among colonies differed significantly, ranging from 23.80-78.48 mg/g/day. This large intraspecific variation raised a question of whether differences in feeding activity reported for other termite species were due to interspecific differences. When rates were expressed as mg wood consumed by one g termite per day (mg/g/day), termites of larger body weight appeared to consume less wood. This negative correlation, however, was not significant when rates were expressed as mg wood consumed by an individual per day (mg/worker/day).
N-Y Su, J P La Fage


Copper naphthenate-treated Southern Pine pole stubs in field exposure. -Part 2: Chemical characterization of full size pole stubs 12 years after treatment
2000 - IRG/WP 00-30246
This study examines the influence of pre-treatment and post-treatment steaming on the character and physio-chemical nature of copper naphthenate in hydrocarbon solvent treated pine in larger, pole diameter, pole stub-length samples. This work is the continuation of two projects that began almost a decade ago. Previous reports indicated that certain morphological changes might occur in small laboratory steamed samples of copper naphthenate treated southern pine. Toluene-methanol extraction, UV-Vis spectroscopy, X-ray diffraction (XRD) and environmental scanning electron microscopy (ESEM) were used to investigate the nature and properties of the copper naphthenate present in the wood after 12 years of exposure. The formation of solid cuprous oxide occurred regardless of pre- or post-steaming conditioning.
H M Barnes, D P Kamdem, M H Freeman


Soil chemistry and wood decay
1978 - IRG/WP 2109
Soil is a most complex biological, chemical and physical material; its study is effectively a separate branch of science but almost entirely in relation to ist ability to grow plants - this paper is intendet just to note some known facets that might have relevance to the decay of wood and the performance of wood preservatives.
E A Hilditch


Immunogold labelling of size marker proteins in brown rot-degraded pine wood
1990 - IRG/WP 1428
Pine wood degraded by Fomitopsis pinicola was infiltrated with a mixture of ovalbumin (45 kDa) and myoglobin (16.7 kDa). After crosslinking of the proteins with glutaraldehyde and preparation for electron microscopy ultrathin sections were labeled with gold-conjugated antibodies. Simultaneous labeling of both proteins on the same section showed that at 50-70% weight loss ovalbumin did not penetrate the brown rot-degraded wood cell walls at all, while partial penetration was observed with myoglobin. Considerable areas of the wood cell walls were not penetrated even by the small myoglobin molecules, although extensive degradation was evident. The results suggest that not only the initial brown rot attack, but all chemical reactions taking place inside the wood cell walls, depolymerization of cellulose to soluble oligosaccharides as well as lignin modification, are caused by a low molecular weight fungal agent.
E Srebotnik, K Messner


Report on questionnaire: Facility for accelerated stake tests in unsterile soil
1983 - IRG/WP 2169
In October 1981 a questionnaire (IRG Doc. No. IRG/WP/2166) on the so-called fungus cellar tests in unsterile soil was prepared and despatched to 56 individuals representing various institutes, organisations, or companies. In addition a further 68 letters describing the purpose of the questionnaire were sent to additional IRG members who could request the full questionnaire if appropriate. This represented a contact with 125 individuals in 48 countries. A verbal report on the results of this survey was presented at IRG 13 in Cesme, Turkey. The present document formalises that report.
J A Butcher


A method to evaluate the effeetiveness of bait application using a transferred nest of Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae)
1999 - IRG/WP 99-20161
Although a survey of monitoring stations can tell us the decline of termite activity after application of baits, it seems questionable to conclude an eradication of a Whole colony of subterranean termites if the termites move out their foraging territory. Only reliable method to ensure the success of bait application is to determine the absence of living termites in their nest in accordance with a survey of monitoring stations. A nest of Coptotermes formosanus was first collected from the field and buried back into the soil with some wooden blocks in a test site. Monitoring stations were installed around the nest to examine termite activity. After termites settled down well, mark-release-recapture was applied to estimate foraging population and then bait application was initiated. When foraging activity ceased, the nest was dug out to find any live termites present. This technique allowed us to draw out a conclusion that baiting eliminated a whole colony of C. formosanus.
K Tsunoda, T Yoshimura, H Matsuoka, Y Hikawa


Preference of the Formosan subterranean termite for wood previously damaged by conspecifics
1988 - IRG/WP 1338
In a laboratory choice test, groups of termites from five colonies of Coptotermes formosanus Shiraki were presented with wood blocks which had sustained previous termite damage: 1) by nestmates, 2) by conspecifics from another colony, 3) by another termite species, Reticulitermes virginicus Banks, and 4) no damage. Coptotermes formosanus preferred wood previously damaged by conspecifics over that damaged by Reticulitermes virginicus. Woodfeeding rate was slightly, though not significantly, higher for conspecific treatments than for controls.
J P La Fage, K S Delaplane


Estimation of the population of a sound colony of Coptotermes lacteus (Froggatt)
1988 - IRG/WP 1353
Selecting an area with a high termite hazard is deemed essential in locating field sites in order to screen potential termiticides and wood preservatives. Yet, quantifying termite populations in such sites remains imprecise. There are major problems associated with estimating populations of termites in mound colonies (either free-standing or in trees), and these are briefly discussed. In this paper we estimate the population of a mound colony of Coptotermes lacteus as 3.06 x 105. The estimate relates to foragers collected at baits that had been inserted into the mound. The technique adopted, "removal sampling", did not destroy the integrity of the mound nor incur unnecessary expense.
D M Ewart, J R J French


Colony elimination of Reticulitermes speratus (Kolbe) (Isoptera:Rhinotermitidae) by bait system
1997 - IRG/WP 97-10189
Following a two-year estimation of the foraging populations and territory of Reticulitermes speratus (Kolbe) by triple mark recapture program at Uji campus of Kyoto University, bait stations (commercialized products containing hexaflumuron) were set up in the foraging territory in October 1995 to eliminate the colony. Inspections demonstrated that the number of test stakes with foraging termites decreased after May 1996. No attack was finally observed in July 1996. As a later inspection in October 1996 reconfirmed no termite hits on any wooden stake in the foraging territory, the colony was considered to be eliminated by baits.
K Tsunoda, H Matsuoka, T Yoshimura, K Yamauchi


Investigation on different variation factors in the results of mycological test and means to reduce and avoid them
1986 - IRG/WP 2264
In order to clarify the causes of the dispersion observed in the results obtained with mycological tests made in accordance with standard EN-113, different factors assumed to be sources of the variations were studied. These included the moisture content of the test samples during the test, the influence of certain technological properties of the wood, the virulence of the fungus strains, the method by which the test pieces were treated and the effect of the solvent, and behaviour of the wood fungus in contact with the wood preservative. It turns out that certain factors which were supposed to be important are actually secondary (humidity). On the other hand, the virulence of the strains is a major problem and requires a serious examination. Treatment by dipping with a ready-to-use product might avoid errors due to obligatory dilutions. In the end, wood species other than beech and Scots pine be used. However, one must not lose sight of the fact that there is a risk that the toxic values may not always be identical.
D Dirol


Size of food resource determines brood placement in Reticulitermes flavipes (Isoptera: Rhinotermitidae)
2000 - IRG/WP 00-10351
Most species of subterranean termite house and care for larvae in specialised chambers or complex nurseries. In addition to these chambers, the genus Reticulitermes also keeps larvae at sites where foragers are feeding, a trait more commonly found in damp wood and dry wood termites. This phenomenon of holding larvae at foraging sites is quite well known among researchers who work with Reticulitermes, yet it has not been investigated to any extent. Consequently, the underlying causes of larvae placement at foraging sites are only poorly understood. During assessments of the resistance of materials to Reticulitermes flavipes attack at the Harrison Experimental Forest, near Saucier, Mississippi, USA, significant numbers of 1 st and 2 nd stage larvae were often found in Pinus spp bait wood stakes. This paper describes the results from the first of a series of ongoing experiments to test whether food resources affected termite presence and larval placement. The experiment used a variable number of pine stakes in eight plots (four in stands of pine, four in grassy forest clearings) where termites were offered a choice of food resources of different size (bundles of 1 to 4 pine stakes of equal size). The number of larvae recorded from feeding sites was a close reflection of the number of workers attracted to a given food source. The more substantial and suitable a food source is, the more foragers will visit it, and in turn the more likely that they will transport larvae and eggs to these feeding sites.
M Lenz, B M Kard, J K Mauldin, T A Evans, J L Etheridge, H M Abbey


Probing red maple pit membrane pore size at FSP and OD using polystyrene macromolecules
2001 - IRG/WP 01-40217
A modified solute exclusion technique was used to pressure impregnate a polystyrene molecular weight (MW) series dissolved in styrene into red maple samples at approximately the fiber saturation point (FSP) and oven dry (OD). Radial penetration was less than tangential and FSP less than OD. There was a marked penetration change with MW in the tangential direction, although there appeared to be a slight decrease in FSP penetration at the higher MW tested.
A Omidvar, M H Schneider, A R P Van Heiningen


Changes in pore structure and cell wall volume in wood decayed by brown- and white-rot fungi
1991 - IRG/WP 1501
Sweetgum (Liquidambar styraciflua L.) wood blocks were decayed by Postia (=Poria) placenta or Phanerochaete chrysosporium in soil-block cultures. Decay was terminated at various weight losses, and the pore volumes available to probes of various molecular weight and diameter were determined by the solute exclusion technique (Stone, J.E. and A.M. Scallan. 1968. Cellulose Chem. Technol. 2, 343-358.). The volume in sound (undecayed) wood that was accessible to the probes varied from 1.0 ml g-1 for the largest to 1.35 ml g-1 for water. Thus, the volume in sound wood attributable to cell wall was 0.35 ml g-1. In brown-rotted samples, the volume of pores in the cell wall increased steadily to 0.7 ml g-1at 35% weight loss. New cell wall volume was accessible to low molecular weight probes but not to molecules of Mr ³ 6,000. Within experimental error, no pores of > 20Å were observed in sound wood or >38Å in brown-rotted wood. Most of the new cell wall volume create by rermoval of components during decay was in the pore size range of 12Å to 38Å. Our results are consistent with the hypothesis that the initial depolymerization of cellulose, characteristic of brown rot, is caused by a diffusible agent. The molecular diameter of the agent is apparently in the range 12Å to 38Å and it causes erosion and thus enlargement of the pores to which it has access. In the white-rotted wood, cell wall volume increased to 0.6 ml g-1 at 40% weight loss and maximum pore diameter increased to 50Å. Most of the cell wall volume increase resulted from the creation of pore of 20-50Å diameter. Analysis of loss of major wood components as a function of weight loss revealed that lignin, cellulose, and hemicellulose were removed at approximately equal rates. Under our experimental conditions, ligninolytic enzymes have access to only a small portion of the new cell wall volume, even after extensive decay.
D S Flournoy


Longterm monitoring of termite activity on multiple feeding sites: a laboratory method intended for the determination of attractant/repellent properties of wood preservatives and baits
2001 - IRG/WP 01-20225
A method is introduced allowing the continuous monitoring of the activity of a small laboratory termite- colony at 8 different feeding sites simultaneously. The test assembly consists of a small central polycarbonate-tube containing a colonie of Reticulitermes santonensis (de Feytaud) beeing connected with 8 external feeding sites by small glass-capillaries. The termites passing through the glass capillaries to and from the feeding sites are interrupting an infrared light-barrier. Each signal from the light-barriers is conditioned and fed to a PC-based signal-recognition-, monitoring- and storage-system. First results show that a colony of 500 individuals of Reticulitermes santonensis (de Feytaud) will need approx. 2 to 3 weeks for establishing a new, full functional hierarchy. A well established Reticulitermes- colony will show 80 to 100 passings per minute to and from the eight feeding sites. The activity of Reticulitermes santonensis (de Feytaud) shows no circadian activity rhythmic.
M Pallaske, E Graf, H Takiuchi


Influence of sampling on the composition of test solutions
1985 - IRG/WP 2235
For four commercial products of CCB-salts the influence of the kind of sampling on the composition of test solutions has been tested. For each product several 5 g samples have been taken at random, after careful mixing the content of each bottle, and after grinding the whole content. With each sample a 5% test solution was made and analyzed on the content of chromium, copper and boron. Altogether 111 solutions were investigated. The results demonstrate, that an at random sampling gives large variations in the composition of the various test solutions and only a grinding of the whole content of a bottle to a fine powdered product ensures a constant composition of test solutions.
H Willeitner, K Brandt


Variance in feeding on equivalent wood blocks by the Formosan subterranean termite (Coptotermes formosanus Shiraki)
1987 - IRG/WP 1325
We tested whether laboratory groups of Coptotermes formosanus Shiraki forage randomly when they are given 4 equivalent wood blocks, and whether group size affects variance of feeding on equivalent blocks. In all cases, foraging was not random, but, rather, the termites concentrated on a few preferred blocks. Group size did not affect this pattern of non-randomness. These data are useful for designing choice tests, and recommended sample sizes for a simulated experiment are given.
J P La Fage, K S Delaplane


Leaching amount of wood preservatives from treated wood in different size during outdoor exposure for 6 months
2000 - IRG/WP 00-50160
Eighteen impregnated specimens with CCA, ACQ, and BAAC preservatives were subjected to a outdoor leaching test. Test specimens, 10 x 10 x 25 cm3, 5 x 10 x 25 cm3, 2 x 10 x 25 cm3 in size, were cut from Japanese cedar (Cryptomeria japonica). Both of end surfaces were sealed with a silicone sealer in the half number of specimens. Total leaching amounts of copper from the open-end ACQ specimens of 10 x 10 x 25 cm3, 5 x 10 x 25 cm3, 2 x 10 x 25 cm3 in size were 76.2 g/m3, 60.6 g/m3, 153.4 g/m3 respectively during 6 months exposure. Those from the end-sealed ACQ specimens were 40.9 g/m3, 50.9 g/m3, 92.7 g/m3 respectively. The ratio of surface area to volume influenced the leaching amount of preservatives. Sealing of end surface of samples reduced the loss of preservatives considerably.
K Yamamoto, S Motegi, A Inai


Mercury porosimetric evaluation of the impregnability of wood
1985 - IRG/WP 2234
Mercury porosimetric measurements for specimens of a given length can not be used to evaluate the treatability of wood. The reason is that the permeability for low permeable woods deviates from Darcy's law with the specimen length. This paper presents a method of evaluation which respects this phenomenon in indicating not only pore size but also a factor describing the pore size as a function of the specimen length. The method has been tested against sapwood and heartwood for white spruce, eastern hemlock and white pine, as well as for reaction wood of white spruce heartwood. A good evaluation of the treatability has been achieved for spruce and hemlock, but not for pine because the intrusion of mercury produces an alteration of its structure.
J P Hösli


Effect of substrate type and moisture requirements in relation to colony initiation in two carpenter ant species
1999 - IRG/WP 99-10320
Conditions necessary for optimal colony initiation or the rate of initial colony expansion by early brood in the carpenter ant species Camponotus modoc and C. vicinus on various substrates conditioned to different moisture contents were studied. Camponotus modoc and Camponotus vicinus queens were placed in Douglas-fir, western red cedar and Styrofoam® blocks conditioned in sealed chambers at 70% or 100% relative humidity. Chambers were periodically monitored for changes in substrate weight, numbers of eggs, larvae, pupae, and worker ants produced. Brood counts produced after thirteen weeks were used to assess the effects of substrate and moisture content on colony initiation. Queens of C. vicinus in Douglas-fir and Styrofoam® produced worker numbers that did not differ significantly with moisture content. However, the number of colonies initiated for C. modoc did significantly differ with moisture content. The results indicate that colony initiation in C. vicinus is less sensitive to moisture content then C. modoc for Douglas-fir and Styrofoam®. No differences were found between moisture contents for ant queens in western red cedar, due to a lack of colony initiation. These results suggest that cedar was detrimental to the development of early brood in both ant species.
M E Mankowski, J J Morrell


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