International Wood Products Journal

Decay problems are responsible for undesirable discolouration of chestnut timber, which lead to a decrease in the value of the wood. As the use of coloured chestnut wood is mainly concentrated on energy fuel, the potential for the use of this coloured wood should be demonstrated. Reference without discolouration and coloured samples from various boards of chestnut wood from Catalonia in north–east Spain were used for the thermal modification at 200°C. The surface colour was determined according to the CIEL*a*b* system before and after the heat treatment as well as after exposure to UV-light. Furthermore, the mass loss, differential swelling and Brinell hardness of untreated and heat treated chestnut samples were also measured. Heat treating homogenises the colour of the reference and coloured chestnut samples and modifies the physical properties. The results of this study demonstrate the possibilities of coloured chestnut wood to develop new applications for it.

The moisture protection of wood coating systems is influenced by the total solid content applied as well as by the hydrophobic properties of the coating film. Water permeability, water vapour permeability and contact angle of water on wood surfaces treated with 21 different coating systems were measured. Water permeability tests were also carried out with artificial mechanical defects of the surfaces. The results showed that the influence of the total solid content applied was predominant, whereas the surface hydrophobicity was less efficient. Systems with a higher total solid content and in particular with continuous coating films showed a higher sensitivity to mechanical defects.

The impact of soil transfer on fungal degradation of Scots pine was investigated using visual inspection, microscopy and DNA profiling. Two test fields in Simlångsdalen with similar soil characteristics were used. Soil has previous been used with the purpose to retain the beneficial original micro-organisms present to imitate field-trials during laboratory condition. We found that fungal degradation in mini-stakes exposed in transferred soil did not correspond to mini-stakes exposed in original soil. Moreover, the type of degradation in the mini-stakes exposed in transferred soil did not match mini-stakes exposed in the original soil. However, established degradation in areas neighbouring the transferred soil was comparable. The fungal community in mini-stakes also varied more between different years than within the field. This suggests that relocation of soil disrupts the original fungal community due to unavoidable mixing of the soil. Therefore, the beneficial micro-organism characteristics of soils is very difficult to transfer elsewhere.

The resistance of thermally modified Canadian Pinus banksiana against four wood decaying fungi was evaluated. Wood samples were treated at different temperatures (190, 200 and 210°C) and exposed to three brown rot fungi as well as to a white rot fungus. Results showed that the untreated wood samples lost more weight when exposed to P. placenta, T. versicolor and G. trabeum compared to the weight loss observed in case of C. puteana. Thermal modification at 210°C improved the resistance of Pinus banksiana against G. trabeum and T. versicolor fungi as evident from the fact that reduction in weight loss of wood was found to be 98·3 and 96·3% respectively.

Chemical modification of fast growing poplar was carried out by impregnating wood with styrene (ST) as an impregnating monomer and in combination with a cross-linking monomer glycidyl methacrylate (GMA). In situ polymerisation was performed by a catalyst thermal procedure. Monomer retention by volume (MR_v) and monomer retention by weight (MR_w) were investigated and the results showed that MR_v of ST-GMA is somewhat more than that of ST, which indicated that the permeability into fast growing poplar of GMA is a little better than that of ST under vacuum pressure process. However, the MR_w of ST was significantly less than that of ST-GMA, which can be ascribed to different monomer density. Then, FTIR spectroscopy analysis showed that cross-linking reaction had happened between wood, ST and GMA due to the presence of both terminal double bond and the epoxy group of GMA. Thermogravimetric and differential thermal analysis (TG-DTA) indicated that the thermal stability of fast growing poplar has been significantly improved after modification by polymer. Scanning electronic microscopy (SEM) observation showed that the vessels and lumens of wood samples were not only uniformly filled by polymers, but also the interface was difficult to distinguish (between cell wall and polymer) after modification by the ST and ST-GMA.

Inonotus hispidus, Scytalidium ganodermophthorum and two strains of Scytalidium lignicola were tested for their ability to produce yellow extracellular pigment on media plates, sterile wood blocks and non-sterile logs to determine their suitability for use as spalting fungi. All three fungi produced a penetrating yellow pigment in the non-sterile logs after 12 weeks of incubation; however, results from the sterile block tests indicated that the incubation time necessary for I. hispidus to produce sufficient yellow pigment may be as low as 4 weeks of incubation. An incubation period of 4 weeks is the shortest recorded for controlled spalting and will allow for the currently utilised production time for yellow spalted wood of 12 weeks to be substantially decreased using an isolate of I. hispidus as the inoculum.

Increasing environmental pressures against deforestation in Central America has increased harvesting restrictions and subsequently caused disruption in the supply of raw materials to primary and secondary industries. A conceptual model was developed based on literature review to describe perceptions of wood products distributors, retailers, and manufacturers regarding supplier and product attributes, retailer/manufacturer and supplier promotion strategies, potential importing barriers and company performance. After verifying internal reliability with Cronbach's alpha, confirmatory factor analysis was conducted to confirm the structure of proposed marketing constructs. Results supported only one of the proposed factors in the model, (i.e. supplier attribute). Exploratory factor analysis was conducted to determine the structure of the remaining factors. The strongest correlations were between product attributes and retailer/manufacturing marketing factors, and the second strongest correlation found was between product and supplier attributes factors. These correlations are critical to developing innovative marketing strategies to increase access to markets in Central America.

Steam distilled essential oil extracts from Port Orford cedar (Chamaecyparis lawsoniana) cones were evaluated for their ability to inhibit the growth of Aspergillus niger and a Trichoderma spp. as well as for their ability to inhibit fungal degradation of wood by Gloeophyllum trabeum, Postia placenta or Trametes versicolor. The extract limited growth by A. niger at the highest dilution level tested (5%) but failed to limit fungal degradation. The results suggest that cone extracts from this species have limited potential for producing bioactive compounds.

Antifungal activity of coconut shell pyrolytic oil against wood decay fungi was explored. Poisoned food technique was employed to indicate the antifungal effect of coconut shell pyrolytic oil against wood decay fungi. The results indicate that there was 81·5% inhibition on the growth of Polyporus sanguineus (L.)G. Mey, (white rot) and 90% inhibition on the growth of Tyromyces palustris (Berk M & A Curtis) (brown rot) at a concentration of 0·25%. This can be attributed to high phenolic content of coconut shell pyrolytic oil.