Abstract

Log yards play an important role in the forest supply chain by connecting raw material supply to manufacturing processes. Log yard design and operations have not been thoroughly represented in the scientific literature, though research in other industrial sectors has demonstrated the strategic operational importance of warehouses. This article investigates the log yard design and operations in current industrial practices.

An analysis of existing log yards was conducted in Quebec. Detailed information about throughput, equipment, personnel, inventory management, and design considerations was gathered by means of questionnaires, on-site visits, and meetings with yard managers.

The survey of current practices (design, management, and operations) confirms that most existing yards have been designed without a systematic method. Crucial performance inhibitors included log yard shape, in-flow management, and poor surface material. Results point toward a potential gain in competitiveness by improving log yard practices, optimizing log yard shape and layout, better coordinating the forest–mill operations, and enhancing surface material.

Abstract

Sawmilling activities in softwood mills (i.e., wood-sawing, drying, and finishing) cannot be efficiently planned at the operational level in a centralized manner because of the complexity of the production process. Sawmills plan their activities in a decentralized manner (although they try to coordinate them). Thus, specific mathematical models have been developed over the years to support planning for each activity. In the literature, these planning models are usually evaluated and tested independently, or connected using heuristics and evaluated for a fixed demand–planning horizon, assuming a known demand for the entire planning period. In this study, we simulate the use of planning models for decentralized sawmill production, but in a context where new orders arrive randomly and replanning is carried out periodically using a rolling horizon. We also simulated and evaluated different coordination mechanisms at the operational level, highlighting that previously published coordination mechanisms for decentralized planning of sawmilling operations may lead to a low order-fill rate when used in such a dynamic environment. We then propose a more advanced push–pull coordination mechanism based on the concept of decoupling point, revealing that this new mechanism may be more appropriate regarding the market characteristics considered in the study, while leading to a sales increase and reduced inventory. Actual numbers vary depending on specific market conditions.

Abstract

This article provides an assessment of fire effects on timber burned in the West Fork Complex fire area, located in the San Juan Mountains of Colorado. The West Fork Complex fire burned 109,615 acres in 2013, and suppression costs alone totaled $33.2 million. Much of the fire occurred in spruce–fir forests that were previously affected by spruce beetle (Dendroctonus rufipennis). Several timber sales were actively occurring within the fire footprint, and more were anticipated to begin in subsequent years. To provide a more accurate valuation estimate, base log stumpage data from 2003 through 2017 were included in this study to show high degrees of variation over time. With base log stumpage values determined, estimates of total hundred cubic feet of each significant species were calculated using geospatial and forest inventory analysis data. This study determined the timber value loss resulting from the coupled disturbance events of the spruce beetle epidemic and a wildland fire to be $19,083,102. This estimate will allow for a more accurate valuation of the actual damage resulting from the West Fork Complex fire. This study may also be useful in supporting the literary basis for salvage and fuels management after a beetle outbreak to prevent such timber value losses from occurring.

Abstract

Lumber grade rules address well-spaced single-knot and combination-knot sizes. Information is lacking, however, with respect to multiple knots in close proximity. The term “well-spaced” appears to lack quantitation. This research investigates the effect that knots in close proximity (not necessarily combination knots) have on the strength properties of southern yellow pine (SYP; Pinus spp.) lumber. This study attempts to use a statistical model to determine the modulus of rupture (MOR) for SYP having multiple knots in close proximity using variables including the knot diameter (KD), amount of clear wood (CW) present, knot area (KA), and modulus of elasticity (MOE) of the lumber. This study investigated specimens of 2 by 4-inch SYP dimensional lumber exhibiting multiple knots in close proximity. The basic density (D) was determined by dividing the entire specimen weight by its volume. Third-point bending tests were used in flatwise orientation to quantify the MOR and MOE. There were significant correlations among all parameters analyzed. Multiple regression analysis with one dependent variable, MOR, and three independent variables, KD, MOE, and D, resulted in a coefficient of determination value (r²) of 0.702. When using only the MOE to predict MOR, an r² value of 0.564 was found.

Abstract

Given the demand for environmentally friendly wood stains, dyeing by fungi has come to light as a suitable process for staining wood, textiles, and other materials. The identification of fungi capable of producing spalted wood merits considerable effort by researchers, and some spalted color or styles found on wood in the wild cannot be cultivated in the laboratory. To find additional fungal candidates and styles for spalting in China, we here collected and identified wood fungi in Yunnan and Guangxi in China. Fungi were purchased or isolated and then inoculated to alder wood blocks (Alnus nepalensis D. Don). Out of seven purchased strains, three formed zone lines, but it was unclear whether Chlorociboria aeruginascens cfcc 87397 could do so. Out of 20 strains, 15 species were isolated from wood forming zone lines with surface black pigments, and only Diaporthe sp. ZXH63-4 formed additional yellow pigments accompanied by zone lines throughout the wood, which is a new means of forming yellow pigments and black zone lines at the same time. Some fungi collected from stained wood samples showed reddish-brown zone lines, but they showed black zone lines when isolated and inoculated on alder.

Abstract

Internal decay is a common problem in poles or timbers of thin sapwood species. Several internal treatments have been developed to arrest this attack, and these systems are widely used in North America. Although these treatments have been evaluated in numerous independent field trials, there is no single test of all treatments. The objective of this study was to assess the chemical distribution and fungal colonization in Douglas-fir poles treated with each of 13 different internal remedial treatments over a 10-year period. Metam sodium treatments provided the shortest protective period, with little evidence of residual chemical 3 years after treatment. Methylisothiocyanate (MITC) in pure form provided a very high initial flush of active ingredient and a longer protective period extending from 5 to 8 years after treatment. Dazomet, which must decompose to produce MITC, took slightly longer to reach effective levels, but was still present at effective levels 10 years after treatment. Chloropicrin, which has strong interactions with wood, was associated with the highest chemical levels after 10 years. Borates took longer to reach effective levels in the poles and their protective zone was narrower than the fumigants, but boron was still present at effective levels 10 years after application. The results illustrate the different properties provided by each treatment, but also show that all tested remedial treatments were effective within certain limitations.

Abstract

The properties of several modified wood products were evaluated using North American standards to provide comparative data for architects seeking to use these materials. In general, modified wood products had lower moisture uptakes and less shrinkage than unmodified products. Acetylated materials were highly resistant to fungal decay, whereas thermally modified and furfurylated materials were classified as decay resistant. All materials were susceptible to mold, although the nonacetylated moisture-resistant medium-density fiberboard was most susceptible. Thermally modified and furfurylated materials were similar in mold susceptibility to untreated radiata pine sapwood, whereas acetylated materials appeared to be more mold resistant.

Abstract

The focus of this study was to observe the properties of bamboo plastic composites modified with a self-made modifier, 18 acyl-dopamine (0, 0.25, 0.50, 0.75, 1.00, and 1.25 weight percent [wt%] based on the dry weight of bamboo powder). The effects of the modifier were demonstrated by measures of mechanical properties, water absorption, thermal stability, and scanning electron microscopy (SEM). The results revealed that 18 acyl-dopamine could be used as an effective modifier of bamboo powder/high-density polyethylene composites. When the modifier was increased, the toughness of the composite deteriorated, and the strength and rigidity improved. This indicated that when the dosage became higher, the compatibilization became stronger, and the toughening effect became worse. Based on the experimental data, a small dosage modifier acted as a toughening agent; as the dosage increased to 1.0 wt%, the compatibility began to appear. The modifier reacted with the hydroxyl groups on the surface of the bamboo powder, which caused the bamboo powder to absorb less water, so the thickness expansion rate was lowest at 1.25 wt%. The pyrolysis peak of bamboo powder and plastic showed a tendency to be close to each other, indicating that the interface was improving. Based on the equation of Flynn-Wall-Ozawa, as the dosage of the modifier increased from 0.50 to 1.25 wt%, the apparent activation energy also increased. The SEM analysis showed the binding between bamboo powder and the plastic matrix was strongest when the modifier dosage was 1.25 wt%.

Abstract

In order to effectively use the waste produced during lumber sawing, the thermal conductivities of wood composite mats shaped by thermoforming and composed of wood shavings, kenaf fibers, and binders were examined by assuming a one-dimensional heat transfer process that could be described by the sum of its heat conduction and radiation components. To improve the heat-insulating properties of the mats, various types of auxiliary raw materials were examined. Mat density depended on the volumetric ratio of the air layer inside the mat to the fiber layer. In the low-density region, increasing the mat density decreased the magnitude of the radiation component and thus the thermal conductivity of the mat, whereas in the high-density region, increasing the mat density increased the value of the conduction component, which in turn enhanced the thermal conductivity of the mat. The minimum value of the thermal conductivity obtained under all experimental conditions is 0.062 W/m·K. Thus, it is difficult to decrease the thermal conductivity of the mat below 0.060 W/m·K by varying its density and mixing ratio. The utilized model predicted that mat thermal conductivity would be less than 0.060 W/m·K if the fibers with a density similar to that of Japanese cedar wood (0.40 g/cm³) were used.

Abstract

Expanding the use of eco-labeled wood flooring in China is an important step in achieving the country's sustainable development goals. For a deep understanding of the relationship between the knowledge of the eco-label and consumer preferences for certified wood flooring in China, this study assessed consumers' purchase intention (PI) and price premium (PP) for Forest Stewardship Council (FSC)- and China Environmental Labeling (CEL)-labeled wood flooring versus nonlabeled wood flooring. A total of 367 face-to-face interviews were conducted at building material markets in Chongqing City with visitors planning to purchase wood flooring in March 2018. The results showed, first, that 21 percent of respondents knew the FSC label, and 65 percent of respondents intended to buy FSC-labeled wood flooring with a PP of 41 CNY/m². Second, 46 percent of respondents knew the CEL label, and 81 percent of respondents intended to buy CEL-labeled wood flooring with a PP of 48 CNY/m². Third, the knowledge of the FSC label positively affected consumers' PI and PP, but the knowledge of the CEL label only influenced PI for certified wood flooring. This study showed that the eco-label knowledge played a main role in consumer preferences for certified wood products and suggested that different strategies should be considered in promoting FSC- and CEL-labeled wood products in the Chongqing market.

Abstract

Using export panel data for China and 24 bamboo and rattan trading partners from 2007 to 2017, this study simulates the export trade of Chinese bamboo and rattan products using a gravity model. Our results showed that economic size has a significant positive impact on the bilateral trade of bamboo and rattan products, while absolute distance between two major economic centers and population size have a significant negative impact. Furthermore, relevant Asia-Pacific Economic Cooperation (APEC) trade arrangements have an impact on bamboo and rattan product trade flows from China. Meanwhile, trade of bamboo and rattan between China and APEC countries such as South Korea, Canada, Russia, and Thailand shows much room for growth.