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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
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
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
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
Nitrogen content of soils at field sites
1981 - IRG/WP 1133
Nine participants in the Collaborative Field Experiment submitted samples for nitrogen analysis to this laboratory as requested by Leightley (IRG/WP/3162). These arrived in a variety of conditions e.g. wet, dried, sterilised and unsterilised and sometimes spent a considerable time in transit. Soils varied in cellular fraction organic matter content, some were obviously sieved prior to postage while others contained significant quantities of large vegetative detritus. Samples were also taken at different times of the year and seasonal and climatic factors may have influenced the values subsequently obtained by analysis.
B King, G Mowe
Collaborative field experiment. Questionnaire re site/soil
1980 - IRG/WP 3162
L E Leightley
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
Soft-rot problems with treated hardwoods: A paper for discussion and establishment of a programme of work
1974 - IRG/WP 331
At the 5th meeting of IRG in Lahti (June 1973) it was decided that an ad hoc group should be formed to study these problems. It was decided that it's activity could be usefully directed in two main areas; a) in the encouragement and direction of existing research in this field, and b) in the organising of a collaborative field trial involving interested parties using locally important hardwood species and existing preservatives. A third area of work is suggested, namely the compilation of existing hardwood field trial results (with hardwood species other than beech) and the bringing together of service experience with treated hardwoods in ground contact.
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
Termite-tunnels formation on the surface of termite-resistant wood species in field sites
2001 - IRG/WP 01-10400
In this report, termite-tunnels formation by the subterranean termite, Coptotermes formosanus Shiraki on the surface of termite-resistant wood species, namely, Hinoki (Chamaecyparis abtsu), Yoshino Hinoki (Chamaecyparis abtsu), Miyazaki Hinoki (Chamaecyparis abtsu), Hiba (Chamaecyparis abtsu) and Japanese cedar (Cryptomeria japonica) was conducted in field sites. Westernhemlock (Tsuga heterophylla), Douglas- fir (Pseudotsuga taxifolia) and Ryukyu pine (Pinus luchuensis) were used as the control. 62 The termite-resistant woods species were classified either as heartwood timber (H) or sapwood timber with a heartwood center (S) and also classified based on their prefecture of origin. Otherwise, the termite- resistant wood species for the termite test were examined in using the forms on the surface of all the termite-resistant wood species by the subterranean termite, Coptotermes formosanus Shiraki. It was found that even for termite-resistant wood species treatment with preservative chemicals is required.
Y Kadekaru, K Kinjo, S Yaga
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
Comparative performance of copper azole and copper-chrome-arsenate treated rubber wood in Australian, Malaysian and New Zealand tests sites
2000 - IRG/WP 00-30213
Rubberwood (Hevea brasiliensis) has been used for non-structural products where appearance is important. It has rarely been used for structural uses where preservative treatment is required. In order to evaluate the in-ground durability of preservative-treated rubberwood, test stakes (20 x 20 x 500 mm3) were treated to four retentions of CCA and copper azole (Tanalith® E) and installed in test sites in Australia, Malaysia and New Zealand . After 2- 4 years exposure, copper azole is out-performing CCA at equivalent retentions where a fungal hazard dominates. At the Malaysian test site, CCA proved the more effective preservative in a severe termite hazard. Neither preservative is likely to adequately protect rubberwood in critical in-ground situations.
J A Drysdale, M E Hedley, E Loh, L T Hong
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.