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A comparison of soft rot, white rot and brown rot in CCA, CCP, CCF, CCB, TCMTB and benzalkonium chloride treated Pinus radiata IUFRO stakes, after 9-15 years exposure at five test sites in New Zealand
1991 - IRG/WP 1485
The aim of this study was to determine if decay type varies significantly between five field trial test sites of different soil type, aspect and climate in 9-15 year old, replicate CCA, CCF, CCP. CCB, TCMTB and AAC treated IUFRO stakes. A visual on-site assessment of decay type on every test stake was made and observations confirmed by microscopical examination. Regression analyses were used to determine significant differences of percentage frequency of occurrence of each rot type between sites and preservatives. Large differences in percentage frequency of occurrence of rot type were evident between sites. One site was dominated by brown rot (85%) and two were dominated by soft rot (99 and 91%). The fourth site had intermediate proportions of brown rot (40%) and soft rot (71%) but had the second highest occurrence of white rot (32%) (highest = 37%; lowest = 11%). The fifth site was distinct in that a large proportion of stakes (69%) had both well established brown rot and soft rot. Stakes at the other four sites tended to have only one rot type. Some highly significant preservative effects were also found. Possible causes of these differences are discussed in terms of inter-site soil type, climate and other differences.
R N Wakeling
Field test evaluation of preservatives and treatment methods for fence posts
1985 - IRG/WP 3347
This work presents the field test results after fifteen years exposure of Eucalyptus saligna fence posts treated with six different preservatives and five treatment methods. All the combinations with oil-borne preservatives presented the best results and among the waterborne preservatives, the fence posts treated by immersion method were with the lowest performance in the field test.
G A C Lopez, E S Lepage
Performance of treated fence posts after 6 years in five test plots in the State of Sao Paulo - Brazil
1976 - IRG/WP 376
Fence posts treated with creosote, pentachlorophenol and creosote/ pentachlorophenol mixtures showed good performance after 6 years of exposure in five test plots located in the State of Sao Paulo - Brazil. Good results were also achieved with copper sulphate/sodium arsenate and copper sulphate/potassium dichromate mixtures. Fungi and termites were the main destroying agents found attacking the posts.
M S Cavalcante
Results of stake tests on wood preservatives (Progress report to 1974)
1975 - IRG/WP 361
A number of field stake trials on preservative-treated wood have been carried out at Princes Risborough Laboratory from 1928 to the present day, and many of the tests still continue. This paper presents in detail the results obtained to date, covering about 15 000 individual test stakes exposed over the period.
D F Purslow
In-ground performance of two formulations of chlorothalonil after five years of exposure at three test sites in Australia
1996 - IRG/WP 96-30101
Sapwood specimens of Pinus radiata D. Don and Eucalyptus regnans F. Muell. were each treated to three retentions of each of two preservative formulations (chlorothalonil in oil; chlorothalonil plus chlorpyrifos in oil) and installed in-ground at three field test sites in Australia. Specimens were treated with each formulation to achieve 3.2, 6.4 and 12.8 kg/m³ of chlorothalonil a.i. and 3.2 + 0.2, 6.4 + 0.4 and 12.8 + 0.8 kg/m³ of chlorothalonil plus chlorpyrifos a.i. For comparison, specimens of each timber species, treated to a commercial in-ground retention of a copper-chromium-arsenic (CCA) formulation, were also installed. Treated specimens (including controls) have been rated for their condition annually for attack by subterranean termites and fungal decay using a scale ranging from 4 (sound) down to 0 (failed). After five years of exposure, mean termite and decay scores for replicate test specimens at each site reveal that the performance of all three retentions of each formulation, particularly the two highest retentions, is comparable to CCA.
J W Creffield, T L Woods, N Chew
An in-ground natural durability field test of Australian timbers and exotic reference species. Part 2: Progress report after approximately 13 years' exposure
1983 - IRG/WP 1189
The condition of heartwood specimens of Australian and exotic timber species after approximately 13 years' in-ground exposure is given. Four of the 5 test sites have a termite hazard in addition to the hazard from a range of decay fungi. Values for specimen life are given only where all replicates of a timber species have become unserviceable. Results give evidence leading to doubt about the accuracy of the tentative durability ratings previously ascribed to at least some of the species under test.
J D Thornton, G C Johnson, I W Saunders
IRG WG III - World-wide co-operative field experiment
1977 - IRG/WP 383
Performance of treated spruce in Canadian field test sites
1989 - IRG/WP 3506
Spruce material under test in Canadian field test sites is performing better than anticipated. From the comparison of the performance of spruce treated with various preservatives, it appears that penetration may be far more important on durability performance than the preservative itself or the retention of preservatives in the wood. However, there is still insufficient data on the influence of penetration on the performance of treated spruce. As data for species other than white spruce and data for sawn material is also incomplete, spruce cannot be accepted by the Canadian standards at this time.
J P Hösli, E E Doyle
Results of field tests on the natural durability of timber (1932-1975)
1976 - IRG/WP 3105
This paper describes a continuing field stake trial to determine the natural resistance of different species of timber to decay. Data are presented for about 180 timbers, covering over 6000 stakes, and the results are discussed in terms of a natural durability classification.
D W Purslow
Natural durability of wood in ground contact - A correlation between field and laboratory tests
1985 - IRG/WP 2182
A field test is being carried out to evaluate the natural durability of 20 hardwoods. The resistance to decay and termite attack was evaluated in accelerated laboratory tests. The results of the field test after 6 years and 8 months indicate that there is not necessarily agreement between results from laboratory and field tests. It is pointed out that apart from the artificiality of the laboratory tests, a possible cause of the discrepancies can be the different performance of the same wood species in different test sites.
M S Cavalcante, G A C Lopez, R G Montagna, M E S Fosco Mucci
Co-operative field trial. Background notes and questionnaire for field sites
1992 - IRG/WP 92-3733
The first co-operative field trial was designed to study the occurrence of soft-rot in CCA treated hardwoods. Generally speaking very similar results were obtained from the different field sites. In the early part of the trial considerable variability was evident with regard to the rate and type of attack which occurred in the untreated material. With the CCA treated timber the type of decay was predominantly soft-rot. It cannot be assumed that with alternative preservatives that the same mode of failure will be as dominant. In such cases the treated timber in different sites may well perform differently. On the other hand, the pattern of failure may be very similar between sites with variation in rates of decay being more evident due to differing distribution of the causal organisms. Tolerant soft-rot fungi tend to be ubiquitious but this is not necessarily the case with other groups. After consideration in the sub-group it was decided to study the variability between sites with regard to the performance of a range of preservatives in a limited number of wood species. A standard CCA preservative would also be included as a point of reference. The overall objective of the trial was very simply summarised as follows: "To identify the number and type of sites required to have confidence in approving a wood preservative". This overall objective has the great attraction that it takes into account all the possible objectives raised in the discussion. It offers the scope to provide data and material to study a whole range of problems and factors of interest to the members, and of international importance when assessing and predicting the performance of wood preservatives.
D J Dickinson
Final proposals for a field experiment to determine the performance of preservative treated hardwoods with particular reference to soft rot
1976 - IRG/WP 367
A series of hardwood stakes have been prepared and treated in the UK from samples (mainly sapwood) supplied from participants around the world. The stakes include 4 reference species common to each site and, in most cases, at least 2 local species of importance. The treated stakes will be despatched to the co-operating scientists and installed under local conditions. It is hoped that with periodic assessment it will be possible to build up a picture of the performance of a range of economically important species throughout the world.
D J Dickinson
The mathematical study of test plot data
1987 - IRG/WP 2282
It has long been desirable to have a mathematical expression, which, by the insertion of statistically derived constants, would describe the behavior of test specimens in service. The philosophy of such expressions is briefly discussed, and the history of the concept is outlined. The modern approach to the problem dates from the graphical presentation of dosage-response and deterioration curves by Colley (1970). In 1972 Hartford devised the "Performance Index" giving a numerical parameter which could give statistically valid comparisons between preservatives in a given installation. A more potent tool is the "log-probability" method, which is now under consideration by AWPA P-6 as a standard. If "log score" is converted to probits x the relationship: x = a + b ln t + c ln R holds well for penta and creosote test specimens at log scores above 30, and tends to give conservative estimates of performance when early results are evaluated. With CCA, this is not true. Recent availability of 19-20 year test results on CCA stake and panel tests (Leach 1986) has permitted the evaluation of "modified probits" as the x in the above equation. Preliminary work shows promise: the CCA results are improved and low log scores can be used. Preliminary data are available on various CCA formulations and stake vs. panel tests.
W H Hartford
An Australian test of wood preservatives. Part 1: Preservatives, principles and practices
1978 - IRG/WP 2123
Between November, 1963, and July, 1964, a graveyard test of some 6000 preservative-treated stakes was installed at 8 sites equally distributed between Papua New Guinea in the tropics, through Queensland and New South Wales to Victoria. More than 40 different preservatives and preservative mixtures, mostly at several different levels of retention, were used to impregnate sawn specimens of Pinus radiata and of Eucalyptus regnans sapwood. Many of the treatments were also duplicated in natural rounds of Eucalyptus regnans of small diameter consisting almost entirely of sapwood. The preservatives included in the test are listed together with sufficient details of preservative retention, treatment procedures and specimen preparation for a full understanding of the comprehensive nature of the test. In addition, a description of the test sites, of the method of inspection and of the manner in which the inspection results are handled has been set down so that the store of data available from this test might be more widely known.
Subterranean termite attack potential in field test sites: assessment methods and field characterization
2003 - IRG/WP 03-10472
To assess subterranean termite attack potential in the field and seasonal variations, trials were set up in each of two managed silvicultural plantations, of Eucalyptus globulus and Pinus pinaster, respectively. Termite occupancy in lying dead wood was evaluated by an adaptation of the line-intersection method, and attack potential in soil was assessed by a system of stakes inserted into the ground, combined with baits. Occupancy in fallen dead wood was assessed over one year, demonstrating that there were seasonal changes in foraging activity. Baits and stakes were assessed at three month intervals, providing a corresponding measure of the intensity of the foraging activity under ground. The usefulness of this dual characterization of field sites is discussed.
T Nobre, L Nunes, L Brinca, D E Bignell
Effectiveness of wood preservatives by IUFRO's method
1984 - IRG/WP 3305
Pinus elliottii and Eucalyptus saligna stakes treated with 4.9; 6.9; 9.6 and 13.5 kg/m³ of CCA-A, CCA-C and CCB and with 30-50; 60-80; 90-110 and 120-140 kg/m³ of Benzotar and CNSL (cashew-nut shell liquid) were exposed in seven test sites in Sao Paulo State, Brazil. After 4 years it was concluded that the mean useful life of untreated Pinus elliottii stakes was 8 months and of untreated Eucalyptus saligna was estimated in 42 months; CCA-A, CCA-C and CCB showed better performance than Benzotar and CNSL, which, in turn, showed similar performance to fuel oil treated series; Eucalyptus saligna 4.9; 6.9 and 9.6 kg/m³ CCA-A and CCA-C treated showed better performance than Eucalyptus saligna treated with the same retentions of CCB; CCA-A and CCA-C showed similar performance for both wood species in all retentions
G A C Lopez, E S Lepage, O B Neto
Performance of copper-chrome formulations in ground contact in five test sites in New Zealand
1996 - IRG/WP 96-30113
Copper-chrome-arsenate (CCA), copper-chrome-boron (CCB), copper-chrome-fluoride (CCF) and copper-chrome-phosphate (CCP) have been tested at four retentions each in ground contact (25 x 50 x 500 mm³ radiata pine sapwood stakes) for 16 years in five test sites in New Zealand. Results to date show that test site characteristics have a marked effect on relative performance. In a warm and wet site (annual rainfall 2000 mm) where soft rot and brown rot predominate, there is very little difference in performance between formulations at equivalent total active element retentions. In drier sites (annual rainfall 1250-1500 mm), where brown rot is more active, CCA is significantly more effective than the other formulations and in a very wet site (annual rainfall >3500 mm) CCB and CCP are most effective formulations. Results are discussed in relation to how climate and soil characteristics influence composition of the fungal flora and their combined effects on preservative efficacy.
M E Hedley, R N Wakeling, J Foster, B E Patterson
Hardwood Field Experiment: Progress Report 1977-1986
1986 - IRG/WP 3391
The international hardwood field experiment was planned in l976 and set up in same 30 different sites around the world. The test stakes include 4 reference species common to each site and in most cases at least 2 species of local importance. It was hoped that a picture of performance of a range of economically important species would be built up and at the same time provide vital background information for people currently engaged in hardwood and soft-rot research. It is felt that these aspirations are more than being achieved and that as time proceeds this trial will prove invaluable in developing our knowledge of wood preservation on a world wide basis. Obviously it proved impossible to set up such a large trial simultaneously. Different sites also inspect their trials at different times and so the data presented is for different periods dependent on the site. The original intention was to fully present the data at year 10 when it is considered the test should be terminated. Two progress reports have been prepared giving details of the reference species (WP3164) and of the mixed species at the master site (WP3200). The sending of results from the various sites has been rather erratic and despite precise instructions, sometimes in a form making it difficult to interpret the results. However, it is felt that this is not a major problem as all the sites will have their own records and the gaps currently in the records should be easily filled in. In view of this we have decided to compile the available results as raw data together with the omissions. This will enable cooperators to check their data and fill in the gaps in their copy of the report and communicate this to the chairman who will pass it on to the other participants. When the final data is added to the records a final report will be written giving a detailed analysis of the data and drawing any necessary conclusions. The full details of the experimental plan are given in IRG document WP/367. However as many people may have misplaced this document the details are summarised here. Each sample was given a code number consisting of 6 digits. The first two digits indicate the participating country and person; the second two digits indicate the species of timber; and the last two digits indicate the treating concentration of preservative and the sample number. With reference to the list in 2.2 the code number 162305 indicates that 16 = Japan, 23 = Crytomeria japonica, 05 = Untreated controls, sample number 5, 2.2 Species list and participants. Due to late inclusion of some species it was not possible to maintain strict numerical order in the allocation of numbers to the species. Were sufficient material was supplied a replicate set of stakes was installed at Silwood Park, Imperial College, Surrey, UK.
D J Dickinson, S M Gray
The movement of iron into field test stakes
1987 - IRG/WP 2284
Failed and sacrificial stakes recovered from the Westham Island field test site were examined for their iron content. Varying amounts were recorded, which were greatest in the failed stakes. The possible role of the iron taken up by the below ground portion of the stakes, in accelerating the decay process and/or the preservative leaching is under investigation. The reaction of the iron with the chrome azurol S reagent normally used to assess copper penetration, has important implications when measuring the penetration of chromated-copper and ammoniacal copper preservatives in field test material.
J N R Ruddick, P I Morris
Above and Below-Ground Depletion of Copper, Chromium and Arsenic from Pinus radiata and Fagus sylvatica at Thirteen Test Sites in New Zealand and Australia
2006 - IRG/WP 06-30402
The objective was to determine the significance of site and wood species on preservative depletion for a copper chrome arsenate preservative (CCA) from 20 x 20 x 500 mm field test stakes after 5.5 and 4.5 years for pine and beech respectively. At least 5 sacrificial stakes were used to produce site means. Site and wood species had a major effect on copper, chromium and arsenic loss from CCA treated pine and beech. At the most severe site above and below ground percentage losses for pine were, 36 and 73 for copper, 22 and 22 for chromium and 31 and 49 for arsenic. At the least severe site losses were close to zero for both above and below ground. Based on mean loss across all sites, the above ground portion of CCA treated pine lost less than 1% copper compared to 8% for chromium and 15% for arsenic. Increased copper (30%) loss for the below ground portion compared to the above ground portion (<1%), was much greater than for chromium (8 versus 9%) and arsenic (15 versus 22%). Whereas copper loss was most affected by below ground exposure for pine, for beech arsenic was most affected. All three elements were more susceptible to loss from beech than pine for both above and below ground exposure, except below ground copper (30% loss for pine and 28% for beech). Arsenic in particular was more susceptible to loss from beech for both above ground (32% for beech versus 15% for pine) and below ground (53% for beech versus 22% for pine). The finding that waterlogged sites, and/or sites with low pH caused greatest loss to all treatments irrespective of wood species, in the light of low loss at horticultural sites suggested that the influence of extremes of water availability and of low pH was more important than other mechanisms such as cationic exchange reactions with soil. Particularly high loss occurred at sites where soil was likely to have contained a high organic acid concentration.
Above Ground Field Testing – Influence of test method and location on the relative performance of various preservative systems
2008 - IRG/WP 08-20393
Standardized above ground tests such as the lap-joint or test deck methods can be very slow in producing useful information on the relative performance of wood preservative systems. It often requires many years for decay to develop in wood treated to sub-optimal concentrations of standardized preservatives, making relative comparisons of performance between new systems and established preservatives difficult. In certain wet locations, the ground proximity method provides much more rapid decay, but its relevance to the majority of above ground environments can be debated. This paper presents work on modifications of a “sandwich” exposure as a possible alternative test method, and provides preliminary data on the performance of known preservative systems in several exposure locations with these and more traditional above ground test methods.
Above ground testing at tropical test sites, what have we learned?
2011 - IRG/WP 11-20473
Three different above ground test methods have been utilized at a selection of five tropical and sub-tropical test sites with a variety of treated and untreated material. The results show that a multi-site approach to above ground field tests presents the opportunity for exposure to un-predicted biodeterioration hazards, which may be important for developmental products of poorly characterized fungicidal performance. The results also show that for tests exposed above ground on racks or fences, high climate index sites may benefit from canopy exposures of the samples rather than open field exposures. The Lap-joint test data from this study suggests that this method is a poor choice for providing rapid results even at test sites with high decay hazards
A Preston, A Zahora, Y Cabrera, L Jin, C Schauwecker, P Walcheski
Performance of Wood Protection Systems at Multiple Field Test Sites Using the Ground Proximity Test Method
2012 - IRG/WP 12-20499
A series of preservative systems were used to treat southern pine ground proximity test samples which were then exposed at a range of test sites located throughout the world. The sites were chosen on the basis of having vastly different Scheffer Climate decay indices. After almost 14 years exposure, distinct differences are apparent in how different preservative systems perform at the different sites, as well as how their relative performance is impacted at different retentions.
A Zahora, A Preston, L Jin
Knowledge exchange and transfer from academia to industry in the field of wood protection research – Activities of the IRG-WP Communications Committee
2019 - IRG/WP 19-50354
The International Research Group on Wood Protection (IRG) was founded in 1969 as a structured group of like-minded scientists and technologists focused on generating knowledge of the science of wood deterioration, and novel solutions to provide sustainably and environmentally responsible products for the protection of wood-based materials. The primary function of the IRG is to provide opportunities for the exchange of ideas and information in an informal atmosphere, unencumbered by refereeing of papers or other pre-conditions. While the primary vehicle is the annual meeting usually held in the second quarter of each year with global locations chosen as providing optimal opportunities for interactions between attendees and in settings that are both interesting and economically viable for our diverse attendance from around the world, the changing nature of the inputs into wood protection research over the past five decades, as well as the ever shifting environmental, global and economic influences have led to a desire to provide additional communications vehicles for the IRG members and sponsors, as well as to provide relevant information to the global audience with an interest in wood products protection and the associated research and technologies. This paper addresses the various ways that the IRG Communications Committee has been developing to provide diverse and on-going communications throughout each year.
F Latorre, B Abbott, C Brischke, M Humar, D Jones, E Larnoy, L Nunes, A Preston, T Singh
Evaluation of Decay Resistance of Copper-based Preservatives Treated-Wood exposed to different field test sites in Korea
2022 - IRG/WP 22-20679
In Korea, preservative treated wood is required to have a stamp on the surface which contains information such as wood species, use categories, and the company that treated the wood. Such stamping is necessary to safely and appropriately use the treated wood. Since majority of treated wood is being used outdoor environment, the treated wood must have efficacy against wood decay fungi or termite. In order to obtain information regarding the life span of the treated wood (ie, how long does the treated wood can be used safely), resistance on decay and termite attack was evaluated by the indoor and outdoor field tests. In this paper, the outdoor field test results of ACQ-2, CuAZ-2, MCQ, and CuHDO-3 treated woods were reported, which were installed in 2012 and have been monitored for decay resistance. The tests were conducted at 6 different field test sites in Korea, Wood samples treated with various retention levels have been evaluated annually according to the AWPA standards. It was found that the wood treated with lower retentions than the Korean standard were decomposed. However, the wood with higher retentions were still sound to this day. Therefore, it was concluded that the preservative treated wood manufactured following the standard retentions can be used safely for a certain period of time. It is also expected that continuous evaluation and monitoring of the wood in the test sites would enable us to estimate the longevity of treated wood with various retentions.
W-J Hwang, S-M Yoon, Y Park, Y-S Choi, H-M Lee, J-W Kim