Skip header and navigation

5 records – page 1 of 1.

Biological method to pre-dry lumber with wetwood

https://library.fpinnovations.ca/en/permalink/fpipub39015
Author
Yang, D.-Q.
Date
March 2007
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Yang, D.-Q.
Date
March 2007
Material Type
Research report
Physical Description
62 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Yeasts
Wetwoods
Seasoning
Bacteria
Series Number
General Revenue Project No. 4030
4030
Location
Québec, Québec
Language
English
Abstract
Wetwood, or water pocket, has higher moisture content (MC) and lower permeability than normal wood, which cause problems for lumber drying. The high moisture content of wetwood usually requires relatively long periods for adequate drying; consequently, it causes a high risk for developing checks, splits, crook, bow and twist of lumber in kiln drying. These problems have not been solved by any physical, chemical or mechanical methods yet. Using biological method to pre-dry lumber containing wetwood is a new concept introduced in this project. Wetwood is formed by bacteria growth inside normal wood. Some fungi are able to kill bacteria and to utilize foetid liquid produced by these micro-organisms. Consequently, the permeability of wetwood can be increased and the lumber drying rate can be improved. The present project intends a research on biological method to pre-dry lumber containing wetwood, and to evaluate efficacy and economic benefit of such a biological treatment. Wetwood of balsam fir, sub-alpine fir and aspen was cultured on nutrient media, and several species of bacteria and yeasts were isolated. The bacteria and yeasts were re-inoculated on normal wood of balsam fir. All inoculated micro organisms caused wetwood formation in 2 weeks. The MC of the inoculated wood blocks increased from 41% to 220-240%, whereas the control samples without inoculation reached only 110%. When control samples were dried to a MC of 13%, the inoculated wood samples still had MCs between 80% and 105%. The selection of biological control agents was conducted on both agar plates and on balsam fir wetwood blocks, and 2 fungal candidates demonstrated promising results. The field test showed that pre-treating balsam fir wetwood lumber with the selected best biocontrol candidates, wood stain was reduced by 94%, warping reduced up to 13%, and checking reduced up to 30% compared with untreated controls. Drying time was reduced by 33% (24 hours) compared with drying fresh lumber. CT scanner was able to detect wetwood locations inside a piece of lumber, and the wetwood was identified in heartwood, sapwood or both wood tissues. After the bio-treatment, the wetwood contents of boards were significantly reduced. Economical analysis showed that the biological treatment would cost $4-7/Mfbm depending on treating method used. Reduction of 33% of drying time by the treatment in this study could save energy cost by $6-13/Mfbm depending on kiln drying energy used. The treatment could reduce lumber degrading loss by $8.5-37.4/Mfbm base on this study. The benefit of the treatment is significant, but will be affected by pre-drying operation, kiln type, energy use and drying schedule. The biological treated lumber is resistant to fungal infection during pre-drying period, and the lumber products are clean and free of moulds and stain infection. Acknowledgements We specifically would like to thank Pierre Lemieux, Scierie Leduc, for providing testing wetwood materials. We also appreciate the support and guidance provided by the project’s industry liaison officers: François Saillant, Natural Resources Canada; Léandre Bélanger, Domtar. Their participation was the key to the success of this project.
Wetwood
Seasoning - Predrying
Yeasts
Bacteria
Biological Control
Fungi
Documents
Less detail

Biological method to pre-dry lumber with wetwood

https://library.fpinnovations.ca/en/permalink/fpipub38957
Author
Yang, D.-Q.
Date
March 2006
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Yang, D.-Q.
Date
March 2006
Material Type
Research report
Physical Description
67 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Yeasts
Wetwoods
Seasoning
Bacteria
Series Number
General Revenue Project No. 4030
4030
Location
Québec, Québec
Language
English
Abstract
Wetwood, or water pocket, has higher moisture content and lower permeability than normal wood, which cause problems for lumber drying. The high moisture content of wetwood usually requires relatively long periods for adequate drying; consequently, it causes a high risk for developing checks, splits, crook, bow and twist of lumber in kiln drying. These problems have not been solved by any physical, chemical or mechanical methods yet. Using biological method to pre-dry lumber containing wetwood is a new concept introduced in this project. Wetwood is formed by bacteria growth inside normal wood. Some fungi are able to kill bacteria and to utilize foetid liquid produced by these micro-organisms. Consequently, the permeability of wetwood can be increased and the lumber drying rate can be improved. The present project intends a research on biological method to pre-dry lumber containing wetwood, and to evaluate efficacy and economic benefit of such a biological treatment. Trees of balsam fir, sub-alpine fir and aspen were felled and cut into lumber. Isolation of causal agents was conducted from wet pockets of these wood species by using peptone agar and malt extract agar media. A total of 319 cultures were obtained from the wetwood of these three wood species. Three bacteria and two yeasts were isolated from balsam fir wetwood, 2 bacteria and 1 yeast were more frequently isolated from aspen wetwood, and 2 bacteria and 5 yeasts were obtained from sub-alpine fir. Two bacteria were isolated from the wetwood of all 3 wood species: Shigella sonnei and Pseudomonas fluorescens. Other bacteria and yeasts isolated were identified as Aerococcus viridans, Chryseomonas luteol, Candida boidinli, C. zeylanoides, Cryptococcus albidus, C. laurentii, C. terreus, and Rhodotorula mucileginosa. In addition to these identified bacteria and yeasts, two other yeasts isolated from balsam fir and sub-alpine fir wetwood were unabile to be identified. Six bacteria and yeast isolates were re-inoculated on normal wood of balsam fir; they were A-a (a bacterium isolated from aspen and identified as Shigella sonnei), A-c (a yeast isolated from aspen and identified as Cryptococcus laurentii), B-a (a bacterium isolated from balsam fir and identified as Shigella sonnei), B-c (a mixture of 2 bacteria isolated from balsam fir and identified as Shigella sonnei and Aerococcus viridans), Y-2 (an unidentified yeast isolated from balsam fir), and SaB-2 (a bacterium isolated from sub-alpine fir and identified as Shigella sonnei). The result showed that all of these micro-organisms caused wetwood formation on inoculated normal wood samples in 2 weeks. This result indicates that wetwood formation in trees is not caused by only 1 micro-organism but is more likely caused by several species (either bacteria or yeasts) that can colonise well in the wood of trees. The moisture contents (MC) of the inoculated wood blocks increased from 41.2% to 220-240 %, whereas the MCs of the control samples submerged in a liquid culture medium without inoculation reached only 110%. When control samples were dried to a MC of 13%, the inoculated wood samples still had MCs between 80% and 105%. This result indicates that drying lumber containing wetwood will take double the time required to dry normal lumber without wetwood. An antagonist test using fungal candidates was conducted on agar plates. In this test, 6 potential fungal antagonists and 6 wetwood causal agents (WCA) were used. The six fungal antagonists were Gliocladium roseum (a bioprotectant developed by Forintek), a white isolate of Ophiostoma piliferum (a fungus used in a commercial bioprotectant, Cartapip), a white isolate of Ceratocystis resinifera (an anti-sapstain biological agent used by Chantal Morin at Laval University), Geotrichum sp.A (a white fungus in Deuteromycetes isolated from Jack pine logs, DP3/5B-3a, 1998), Geotrichum sp. B (a white fungus in Deuteromycetes isolated from balsam fir logs, DF3/1B-1b, 1998), and Phaeotheca dimorphospora (a biological control agent of tree disease from Laval University). The six wetwood causal agents were A-a (a bacterium isolated from wetwood of aspen), A-c (a yeast isolated from wetwood of aspen), B-a (a bacterium isolated from wetwood of balsam fir), Y-2 (a yeast isolated from wetwood of balsam fir), SaB-2 (a bacterium isolated from wetwood of sub-alpine fir), and SaY-4 (a mixture of a yeast and a bacterium isolated from wetwood of sub-alpine fir). The results showed that Geotrichum sp.A and Geotrichum sp.B were the most effective against all 6 WCA inoculated; they reduced growth of the WCA in 7 days and completely absorbed colonies of WCA in 11 days. G. roseum, O. piliferum, and C. resinifera were moderately effective against 5 WCAs, but not effective on bacterium A-a that was isolated from aspen wetwood. P. dimorphospora was the least effective against any of these WCA. The three promising fungal antagonists, Geotrichum sp., G. roseum and the white isolate of O. piliferum, selected from agar plate test were used for an antagonist test on balsam fir wetwood blocks in the laboratory conditions. This test was conducted on small wetwood samples (2 x 4 x 1 inch) in incubators at 25°C and two relative humidity ranges (100% and 75% RH). The results showed that all these three fungi were able to establish on wood surfaces and able to reduce wetwood contents. At 25°C and 75% RH, Geotrichum sp. was the most effective to reduce wetwood content in samples, followed by G. roseum, and then by O. piliferum. G. roseum and Geotrichum sp. not only reduce wetwood content, but also inhibit mold growth and wood stain, compared with untreated control samples. At 25°C and 100% RH, the moisture contents of treated and untreated samples were not changed in any week of the testing period. This result indicates that biological pre-dry wetwood samples should not be conducted at this high relative humidity condition. A test was conducted to investigate the inhibitory ability of Geotrichum sp., the wetwood control candidate, against sapstaining fungi on wood. The results showed that if balsam fir wood wafers were inoculated with Geotrichum sp. 3 days before the staining fungi, no staining fungi grew on these samples. If wood wafers were inoculated with Geotrichum sp. and staining fungi at the same time, samples were covered by both Geotrichum sp. and the staining fungus Ophiostoma piceae in a ratio of 1:1. If wood wafers were inoculated with the staining fungi 3 days before Geotrichum sp., samples were absolutely covered by the staining fungus and fully stained. A study on environmental effects on the growth of Geotrichum sp., the wetwood control agent, showed that this fungus started growth at 5°C, had optimal growth between 20-25°C, stopped growth at 30°C, and died at 40°C. Geotrichum sp. had a wide range of pH requirement and grew well in agar medium at pHs between 3 and 10. Geotrichum sp. started to grow at 29% MC, and the speed of the growth increased along with the increase of MC in wood. The best fungal growth of Geotrichum sp. was observed on wood blocks containing 56% MC. Geotrichum sp. was able to grow on wood of jack pine, black spruce, balsam fir, sub-alpine fir and aspen, but it grew better on wood of jack pine, balsam fir and black spruce than on sub-alpine fir and aspen. Geotrichum sp. was able to grow together with an anti-sapstain fungus, Gliocladium roseum, without any antibiotic or incompatible growth reaction. In the laboratory conditions, the biological treated boards reduced wood MC by 22-37% more than untreated boards. Untreated boards were fully covered by molds and stain after 8 weeks in storage, and 0% of boards was acceptable for use. The biological treated boards were less affected, with 35-75% of pieces acceptable. The time required for drying biological treated boards was estimated reducing by 10.5 hours compared with untreated controls. After drying, the biological treated boards reduced the rate of crook, bow and twist by 5-20%, but increased the rate of split and check by 5-12%, compared with untreated controls. The total deformation rate was reduced up to 5% by the best biological treatment. In the field conditions, untreated boards were 100% affected by molds and stain after 8 weeks in storage, whereas the best biological treated boards were only affected by 6%. Drying biological treated and untreated boards took similar times, but it was estimated reducing drying time by 48 hours compared with fresh boards. Compared with untreated controls, the biological treated boards reduced the rate of crook, bow and twist by 2-13%, and reduced the rate of split and check by 3-30%. The total deformation rate was reduced by 5-22%, depending on the treatments. CT scanner was able to detect wetwood locations inside a piece of lumber, and the wetwood present in either heartwood, sapwood or both wood tissues. After the bio-treatment, the wetwood contents of boards were significantly reduced.
Wetwood
Seasoning - Predrying
Yeasts
Bacteria
Biological Control
Fungi
Documents
Less detail

Biological method to pre-dry lumber with wetwood

https://library.fpinnovations.ca/en/permalink/fpipub42290
Author
Yang, D.-Q.
Date
March 2005
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Yang, D.-Q.
Date
March 2005
Material Type
Research report
Physical Description
44 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Yeasts
Wetwoods
Seasoning
Bacteria
Series Number
General Revenue 4030
Location
Sainte-Foy, Québec
Language
English
Abstract
Wetwood, or water pocket, has higher moisture content and lower permeability than normal wood, which cause serious problems for lumber drying. The high moisture content of wetwood usually requires relatively long periods for adequate drying; consequently, it causes a high risk for developing checks, splits, crook, bow and twist of lumber in kiln drying. These problems have not been solved by any physical, chemical or mechanical methods yet. Using biological method to pre-dry lumber containing wetwood is a new concept introduced in this project. Wetwood is formed by bacteria growth inside normal wood. Some fungi are able to kill bacteria and to utilize foetid liquid produced by these micro-organisms. Consequently, the permeability of wetwood can be increased and the lumber drying rate can be improved. The present project intends a research on biological method to pre-dry lumber containing wetwood, and to evaluate efficacy and economic benefit of such a biological treatment. Trees of balsam fir, sub-alpine fir and aspen were felled and cut into lumber. Isolation of causal agents was conducted from wet pockets of these wood species by using peptone agar and malt extract agar media. A total of 319 cultures were obtained from the wetwood of these three wood species. Three bacteria and two yeasts were isolated from balsam fir wetwood, 2 bacteria and 1 yeast were more frequently isolated from aspen wetwood, and 2 bacteria and 5 yeasts were obtained from sub-alpine fir. Two bacteria were isolated from the wetwood of all 3 wood species: Shigella sonnei and Pseudomonas fluorescens. Other bacteria and yeasts isolated were identified as Aerococcus viridans, Chryseomonas luteol, Candida boidinli, C. zeylanoides, Cryptococcus albidus, C. laurentii, C. terreus, and Rhodotorula mucileginosa. In addition to these identified bacteria and yeasts, two other yeasts isolated from balsam fir and sub-alpine fir wetwood were unabile to be identified. Six bacteria and yeast isolates were re-inoculated on normal wood of balsam fir; they were A-a (a bacterium isolated from aspen and identified as Shigella sonnei), A-c (a yeast isolated from aspen and identified as Cryptococcus laurentii), B-a (a bacterium isolated from balsam fir and identified as Shigella sonnei), B-c (a mixture of 2 bacteria isolated from balsam fir and identified as Shigella sonnei and Aerococcus viridans), Y-2 (an unidentified yeast isolated from balsam fir), and SaB-2 (a bacterium isolated from sub-alpine fir and identified as Shigella sonnei). The result showed that all of these micro-organisms caused wetwood formation on inoculated normal wood samples in 2 weeks. This result indicates that wetwood formation in trees is not caused by only 1 micro-organism but is more likely caused by several species (either bacteria or yeasts) that can colonise well in the wood of trees. The moisture contents (MC) of the inoculated wood blocks increased from 41.2% to 220-240 %, whereas the MCs of the control samples submerged in a liquid culture medium without inoculation reached only 110%. When control samples were dried to a MC of 13%, the inoculated wood samples still had MCs between 80% and 105%. This result indicates that drying lumber containing wetwood will take double the time required to dry normal lumber without wetwood. An antagonist test using fungal candidates was conducted on agar plates. In this test, 6 potential fungal antagonists and 6 wetwood causal agents (WCA) were used. The six fungal antagonists were Gliocladium roseum (Forintek bioprotectant), a white isolate of Ophiostoma piliferum (Cartapip), a white isolate of Ceratocystis resinifera (an anti-sapstain biological agent produced by Chantal Morin at Laval University), Oidium sp.A (a white fungus in Deuteromycetes isolated from Jack pine logs, DP3/5B-3a, 1998), Oidium sp. B (a white fungus in Deuteromycetes isolated from balsam fir logs, DF3/1B-1b, 1998), and Phaeotheca dimorphospora (a biological control agent of tree disease from Laval University). The six wetwood causal agents were A-a (a bacterium isolated from wetwood of aspen), A-c (a yeast isolated from wetwood of aspen), B-a (a bacterium isolated from wetwood of balsam fir), Y-2 (a yeast isolated from wetwood of balsam fir), SaB-2 (a bacterium isolated from wetwood of sub-alpine fir), and SaY-4 (a mixture of a yeast and a bacterium isolated from wetwood of sub-alpine fir). The results showed that Oidium sp.A and Oidium sp.B were the most effective against all 6 WCA inoculated; they reduced growth of the WCA in 7 days and completely absorbed colonies of WCA in 11 days. G. roseum, O. piliferum, and C. resinifera were moderately effective against 5 WCAs, but not effective on bacterium A-a that was isolated from aspen wetwood. P. dimorphospora was the least effective against any of these WCA. The three promising fungal antagonists, Oidium sp., G. roseum and the white isolate of O. piliferum, selected from agar plate test were used for a following antagonist test on balsam fir wetwood blocks in the laboratory conditions. This test was conducted on small wetwood samples (2 x 4 x 1 inch) in incubators at 25°C and two relative humidity ranges (100% and 75% RH). The results showed that all these three fungi were able to establish on wood surfaces and able to reduce wetwood contents. At 25°C and 75% RH, Oidium sp. was the most effective to reduce wetwood content in samples, followed by G. roseum, and then by O. piliferum. G. roseum and Oidium sp. not only reduce wetwood content, but also inhibit mold growth and wood stain, compared with untreated control samples. At 25°C and 100% RH, the moisture contents of treated and untreated samples were not changed in any week of the testing period. This result indicates that biological pre-dry wetwood samples should not be conducted at this high relative humidity condition. A test was conducted to investigate the ability of Oidium sp., the wetwood control candidate, against sapstaining fungi on wood. The results showed that if balsam fir wood wafers were inoculated with Oidium sp. 3 days before the staining fungi, no staining fungi grew on these samples. If wood wafers were inoculated with Oidium sp. and staining fungi at the same time, samples were covered by both Oidium sp. and the staining fungus Ophiostoma piceae in a ratio of 50 to 50%. If wood wafers were inoculated with the staining fungi 3 days before Oidium sp., samples were absolutely covered by the staining fungus and fully stained.
Wetwood
Seasoning - Predrying
Yeasts
Bacteria
Biological Control
Fungi
Documents
Less detail

A computer visualization and analysis of wet-wood distribution and related processing alternatives for subalpine fir trees

https://library.fpinnovations.ca/en/permalink/fpipub37634
Author
Alkan, S.
Date
October 2002
Material Type
Research report
Field
Sustainable Construction
Author
Alkan, S.
Date
October 2002
Material Type
Research report
Physical Description
36 p.
Sector
Wood Products
Field
Sustainable Construction
Research Area
Advanced Wood Materials
Subject
Wetwoods
Simulation
Scanning electron microscopy
Scanners
Grading
Balsam
Automatic control
Fir
Series Number
1020
W-1911
Location
Vancouver, British Columbia
Language
English
Abstract
A software, by which virtual 3-D subalpine fir (Abies lasiocarpa [Hook] Nutt) logs can be re-created, visualized, and theoretically sawn an infinite number of times, was developed. The software also facilitates obtaining data for determining quantitative variation of clear wood, wet-wood, and knot patterns within the tree stems. Results based on the quantitative calculations showed that there are two general patterns of wet-wood within the sub-alpine fir stems. The first pattern is called wet-pocket and the second pattern is called wet-streak. Wet-streak patterns are generally confined to the medullary-inner heartwood regions in the outer heartwood and heartwood-sapwood transition zones of the tree stems, mostly associated with dead knots. Wet-pocket patterns consist of portions occurring in mid regions in close proximity to the base and regions mostly around partially dead knots of the tree stems. Both wet-wood patterns usually converge at the nodes and extend along the branch axes, forming a connection with the exterior boundary only around branches. Numerical analysis of the results showed that the volume of both types is more prevalent in the lower-stem regions, becoming less prevalent towards the living crown. The radial extension of wet-wood types with radial distance from the tree centre was variable, with a maximum diameter of 22 cm. Both wet-wood volumes increased with increasing tree age and diameter class independent of age. However, the percentage of total wet-wood volume decreased with increasing DBH, increased stem height and showed no clear trend with age class. Total amounts of wet-wood ranged up to 27 per cent in individual stems. A weak relationship was found between dead knot-pattern and wet-streak pattern volumes, while a moderate high relationship was found between partially dead knot and wet-pocket volumes. A weak relationship was found between external tree characteristics and both wet-wood distributions. As a result, some promising trends emerged for a better understanding of wet-wood and knot pattern variations as influenced by tree stem locations, DBH, and age. The developed software may offer a compelling technique for assisting subalpine fir log processing decisions. However, the destructive data collection method used in this study is “error-prone”. Therefore, an interesting alternative would be the use of more accurate non-destructive scanning techniques, such as CT-scanning, to verify the trends identified here through more deliberate sampling at other forest sites. A new study is already underway to meet this need.
Moisture content
Computer simulation
Abies lasiocarpa
Scanners, Electronic
Defects - Detection
Grading - Automation
Wetwood
Documents
Less detail

Promoting natural biocontrol of wetwood

https://library.fpinnovations.ca/en/permalink/fpipub42444
Author
Yang, D.-Q.
Date
March 2010
Material Type
Research report
Field
Sustainable Construction
Author
Yang, D.-Q.
Date
March 2010
Material Type
Research report
Physical Description
34 p.
Sector
Wood Products
Field
Sustainable Construction
Research Area
Advanced Wood Materials
Subject
Wetwoods
Series Number
General Revenue Report Project No. 201000571
Location
Québec, Québec
Language
English
Abstract
A series of studies were conducted in this project including 1) Evaluating the effect of the wetwood control agent on wood weight loss; 2) Evaluating the effect of the wetwood control agent on wood strength loss; 3) Evaluating the effectiveness of the wetwood control agent on western wood species; 4) Investigating natural distribution of the wetwood control agent in balsam fir logs and lumber; 5) Stimulating natural colonization and enhancing growth of the wetwood control agent; 6) Optimizing biological formulation and shelf life; 7) Studying the feasibility of biological stimulation for natural colonization; and 8) Identifying potential commercial partners, product registration and new substances notification. The results showed that the two wetwood control isolates were able to cause weight losses of the fresh sapwood of balsam fir, sub-alpine fir and hemlock tested; however, the amount of the weight losses caused by the wetwood control agent was significantly lower than the one caused by the true decay fungi. The wetwood control isolates were unable to cause wood strength loss of treated balsam fir lumber after an outside summer storage of 8 weeks. Both isolates of the wetwood control agent grew well on the western wood species such as sub-alpine fir or hemlock and reduced moisture contents from these wood species. A total of 456 cultures were isolated from bark of balsam fir logs, 295 cultures were isolated from the wood of logs, and 110 cultures were isolated from sawn lumber. Among these cultures, 2% of the wetwood control agent were isolated from bark, 6% of them were from wood and 5% from lumber. Studies also showed that pre-treating wood with 1% bleach solution or steaming at 100°C for 10 minutes could stimulate the growth of the wetwood control agent on balsam fir wood. Considering the high efficacy and the low cost, the best formulation of the wetwood control agent was identified as a concentrated spore suspension. Such a formulation could be stored or transported at ambient temperature, at 4°C or at -20°C; however, the highest survival rate was observed from those cultures stored at 4°C, which survived 100% for 3 months and 68% for 6 months. The moisture content loss from balsam fir logs treated with the culture of the wetwood control agent was 43.6% after a 2-month storage period. The potential commercial partners for commercializing this bio-product have been identified.
Wetwood
Biocontrol
Documents
Less detail