Hardwood Logs Research Articles

Validating LORCAT, the Log Recovery Analysis Tool

Abstract The Log Recovery Analysis Tool (LORCAT) is a simulation tool that allows users to examine the impact of changes in the hardwood log-sawing process on sawn volume, grade recovery, and profit. LORCAT was designed to be simple to use and requires a minimum of user data entry. While the results of LORCAT have been informally compared to sawmill results by users, no formal validation of results has yet been performed. This study compared LORCAT’s simulated recovery results to that of an actual sawmill. For the 42 hardwood log samples we examined, we found no significant statistical difference in the total sawn volume produced. However, significant differences were found with the number of boards produced, which resulted from differences in the accuracy of targeting the opening-face board size.

Application of Miscanthus substrates in the cultivation of Ganoderma lingzhi.

Ganoderma lingzhi is a traditional Chinese medicine that has been used to improve health and longevity for thousands of years. It is usually cultivated on hardwood log- or sawdust-based formulations. Conversely, in this study, we used Miscanthus sacchariflorus (MSF), M. floridulus, and M. sinensis (MSS), fast-growing perennial grasses widely distributed in China, for G. lingzhi cultivation. Mycelial growth rate, activities of lignin-degrading enzymes on colonized mushroom substrates, and expression levels of CAZymes and laccase genes based on different substrates were analyzed. Total triterpenoids, sterols, and polysaccharides content of fruiting bodies obtained from different substrates were investigated. The activities of laccase and manganese peroxidase in mycelia increased in the MSF- and MSS-based formulations compared with that in the sawdust-based formulation. The results of mycelial growth- and cultivation-related experiments showed that the Miscanthus substrates could be used as the substrates for cultivating G. lingzhi. The content of activeingredients, namely triterpenoids, sterols, and polysaccharides, in fruiting bodies cultivated on the Miscanthus substrates did not decrease compared with those in substrate obtained from the sawdust-based formulation. Therefore, the present study provides alternative substrates for the cultivation of G. lingzhi, and a reference for better utilization of inexpensive substrate in future.

Timber Production Opportunities from Private Native Forests in Southern Queensland

Historically, Queensland’s private native forests have supplied between 40 and 70% of the hardwood resource to the state’s primary processors. Hardwood timber production from state-owned native forests and plantations in Queensland has decreased substantially in recent decades, increasing the hardwood timber industry’s reliance on private native forests. However, timber production opportunities from these forests are poorly understood. This study assessed the future wood supply capacity from private native forests in southern Queensland assuming alternative levels of landowner interest in management for timber production and willingness to invest in silvicultural treatment. Commercial and harvestable private native forests in southern Queensland were classified into six forest types and their spatial distributions were assessed. Potential growth rates for each forest type were estimated based on available literature and expert opinion, and their ability to supply logs to industry with and without silvicultural treatments was projected. Commercial and harvestable private native forests were found to cover an area of approximately 1.9 M ha in southern Queensland, of which spotted gum (693,000 ha) and ironbark (641,500 ha) forest types are most common. The private native forest estate is distributed over 17,665 landholdings (LotPlans), with 17% of these accounting for 66% of the commercial and harvestable resource. Most private native forests have not been actively managed for timber production and are in poor condition. Nevertheless, they presently have the potential to supply between about 150,000 and 250,000 m3 of logs to industry per annum. Silvicultural treatments were found to have the potential to increase the mean annual increment of these forests by a factor of between two and four, indicating substantial opportunities to increase harvestable log volumes in the medium and long-term. Private native forests in southern Queensland could potentially more than compensate for the supply gap left by the declining area of state-owned native forests that are available for timber harvesting. Actual forest management performed and log volumes supplied to market will depend on the forest management decisions of thousands of individual landholders, which are influenced by their heterogeneous management objectives, the policy environment, perceptions of sovereign risk, timber markets and the long payback periods in forestry. An accommodating forest policy environment and landholder willingness to invest in forest management could maintain and potentially increase private hardwood log supply to industry, which would support farm income diversification and regional employment opportunities.

Impact Analysis of Solar Heater Box with Linear Actuator on Characteristics of Chickpea Seeds

Food security is one of the major concerns of humankind in the present era and a lot of work has been done to ensure the availability of food to the growing population. Post-harvest technology is one of the key components to store the seeds for long duration for consumption as food or grow as seed. The disinfection of seeds during storage from insect pests is one of the major problems that need to be addressed. In this study, an efficient solar box is designed which is operated through renewable solar energy. For this purpose, the solar heater box was prepared of an acrylic sheet (2mm thickness), Lasani sheet (2mm thickness) and hardboard sheet (12mm thickness) which were an octagon in shape with 135oC at the base. A 12v linear actuator was installed in the solar box along with hardwood log (saw tooth-like comb) to equally distribute the heat in the seed place for experiment. The highest thermal performance was generated by an acrylic solar heater box 87.40 ℃ compared to hardboard and Lasani box. However, the material used for assembling acrylic boxes was too costly. A hardboard box was too heavy and the temperature was generated 69.69℃ which was relatively significant to the temperature recorded in Lasani solar heater box (70.19℃) at after 6 hour of an observation. Concerning the financial aspect, the price of each of the three solar heater boxes was estimated based on the cost of the materials used to construct the boxes and the additional labour costs, with the assistance of carpenters during assembly. These costs show how much cheaper the Lasani box is compared to the other prototypes. The temperature at a depth of 6 cm was noted 67.42℃ among Chickpea seeds, whereas the temperature recorded within seeds was 69.61℃. Furthermore, the experiment conducted in RCBD revealed that germination percentage of seeds at a depth of 6cm was observed to be 97% after treatment. The overall conclusion of the study is that the solar box with linear actuator is more efficient as compared to traditional drying method.

IPSO-VMD based signal feature extraction and internal defect detection of hardwood logs through acoustic impact test

Accurate quality detection of hardwood logs can realize efficient utilization of wood and provide significant benefits to wood enterprises. However, due to the differences in the extraction principle of acoustic parameters and the interaction mechanism between the parameters and wood properties, the quality assessment results of hardwood logs are different to some extent. For this, a method for feature extraction of the acoustic signal and defect detection was proposed based on the improved particle swarm optimization-variational modal decomposition (IPSO-VMD). By analyzing the sparse features of defect signals, the minimum mean envelope entropy was set as the fitness function of IPSO optimized VMD to search for the optimal number pair (L, α). And the search for IPSO was accelerated to acquire the global optimal solution by improving the inertia weight and learning factor of PSO. Then, the effective sub-modes decomposed from the IPSO-VMD were selected based on Hilbert marginal spectrum and energy ratio of sub-band components, and the frequency sub-band distribution and energy rates of the effective modes sifted were used as the characteristic parameters characterized the defect signal to realize the accurate quality detection of hardwood logs. The sawing results of the sample logs showed that the major defect types and priorities in logs were detected with an accuracy of 88.4% and 74.4% respectively based on the IPSO-VMD method, even for which not identifiable by global parameters could be also examined effectively. The effectiveness of the new feature parameters can provide a reliable basis for the accurate quality detection of hardwood logs through fusing the multi-parameter features and constructing the artificial intelligence recognition system in the future.

Cover Image

EcologyVolume 104, Issue 6 e4102 COVER IMAGEFree Access Cover Image First published: 01 June 2023 https://doi.org/10.1002/ecy.4102AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Graphical Abstract COVER PHOTO: Oyster mushrooms (Pleurotus ostreatus) fruit from a hardwood log in New Hampshire, USA. In their study in this issue, Borgmann-Winter et al. (Article e4039; doi:10.1002/ecy.4039) compared fungal spores in rodent scat to windborne spores and found that these two dispersal pathways support complementary fungal communities. Wood saprotrophs (such as the oyster mushroom) were among those fungal functional types most common in windborne spore samples, whereas mycorrhizal fungi and soil saprotrophs were among those common in rodent scat. These findings demonstrate the importance of vertebrates in supporting fungal communities, which in turn facilitate nutrient cycling, decomposition, and plant community composition through mycorrhizal symbiosis. Photo credit: Benjamin Borgmann-Winter. Volume104, Issue6June 2023e4102 RelatedInformation

Gradeability of a Forwarder Based on Traction Performance

Based on the knowledge of the dimensional and mass features of a forwarder, a model was developed to assess its mobility during timber forwarding uphill in a safe and eco-efficient way. The model is based on knowledge of the position of the forwarder’s centre of gravity, its declared payload and the length of the loaded timber, as well as the gradeability for uphill timber forwarding based on the traction characteristics of the vehicle. The model connects two research approaches, (1) vehicle–terrain approach (distribution of axle loads depending on the longitudinal terrain slope) and (2) wheel–soil approach (estimation of the traction characteristics of the forwarder based on the wheel numeric), concerning previous research: (i) underload on the front axle of the vehicle, (ii) overload on the rear axle of the vehicle, (iii) permissible tire load, (iv) minimal soil bearing capacity, (v) wheel slip. Simulation modelling for the assessment of the forwarders’ mobility range during timber forwarding uphill was conducted on an example of an eight-wheel Komatsu 875 forwarder, with a declared payload of 16,000 kg, equipped with 710/45-26.5 tires, for which the position of the centre of gravity was determined by the method of lifting the axle. The results of the distribution of the adhesion load on the front and rear axles of the forwarder indicated that, during timber forwarding of 16,000 kg and 4.82 m long hardwood logs on a terrain slope below 68%, there is no critical unloading on the front bogie axle, nor overloading on the rear bogie axle, i.e., wheel tire overload that could limit forwarder mobility. For the specified range of longitudinal terrain slope, a minimal cone index of 950 kPa for an exemplary forwarder is an environmental factor and was calculated based on the nominal ground pressure of the reference (heavier loaded) rear wheels of the vehicle. The forwarders’ mobility range was determined by the intersection curves of the gradeability (based on forwarders’ traction characteristics at wheel slip of 25% vs. cone index) and the curve of the minimal soil cone index.

Effect of Sawing Variation on Hardwood Lumber Recovery—Part I: Volume

Abstract Sawing variation (SV), the degree of deviation from a specified target lumber size, is an unavoidable component of the sawing process. SV is influenced by several factors such as machine, material, set works, feed works, and cutting parameters. To account for these factors resulting in deviations from the desired target size, the target thickness of the lumber cut must be increased such that only a minimal number of boards is less than target thickness. Thus, the greater the amount of SV, the larger the target thickness must be such that a minimal quantity of undersized lumber is produced. Hence, with larger amounts of SV come greater waste and decreased opportunities for optimizing lumber recovery. However, the decrease in material loss due to a reduction in SV may not necessarily translate into a statistically significant increase in lumber product recovery by volume. This study explored the effect of varying degrees of SV on lumber recovery by volume for a range of hardwood log diameters using the US Forest Service's LOg ReCovery Analysis Tool sawmill simulation software. A minimal average recovery improvement of 3 percent due to reduced SV was observed across all kerf thicknesses, equating to a production value improvement of $336,000 for an 8 million board feet mill. Results indicate that the recovery gains realized by volume depend upon the log diameters sawn, the lumber target thickness, and the change (reduction) in SV.

Effect of Sawing Variation on Hardwood Lumber Recovery—Part II: Board Count

Abstract Sawing variation (SV) describes all variations that exist in the production of lumber due to machine, material, set works, feed works, and cutting parameters. The necessary oversizing of board thickness due to SV diminishes sawmill profits and hence efforts must be made to reduce the variation. However, such efforts are costly and sawmill personnel generally do not know at which point efforts to reduce (SV) become more costly than oversizing the boards. In an accompanying paper we examined the impact of SV on lumber volume recovery and found that volume recovery increased comparatively more for thinner than for thicker kerfs and that the effect of reduced SV became more pronounced as diameter increased. In this second manuscript, the effect of SV on the quantity of boards sawn for a range of hardwood log diameters using the US Forest Service's LOg ReCovery Analysis Tool sawmill simulation software was researched and compared with the volume improvement from an earlier paper. Results showed that significant differences in the number of boards obtained was dependent on the log diameters sawn, the lumber target thickness, and the change (reduction) in SV. A minimal average recovery improvement of 3 percent due to reduced SV was observed across all kerf thicknesses, equating to a potential production value improvement of $336,000 for an 8 million board feet mill. All sawmills can benefit from reducing SV, but mills that saw large-diameter logs might consider pursuing SV reduction more aggressively than a sawmill sawing mostly small-diameter logs.

Proteomic characterization of Shiitake (Lentinula edodes) post-harvest fruit bodies grown on hardwood logs and isolation of an antibacterial serine protease inhibitor

Lentinula edodes (Shiitake) is one of the most heavily cultivated mushrooms in the world with proven antioxidant and antibacterial properties, among others. Evidence indicates that the choice of mushroom cultivation technique strongly influences the production of bioactive compounds, but to date the nature of many of these compounds has not been fully established. This work focuses on the proteomic characterization of L. edodes to highlight the main active processes two days after harvest and elucidates the proteins involved in the known antioxidant and antibacterial proprieties of Shiitake fruit bodies cultivated on oak logs. A label-free approach allowed us to identify a total of 2702 proteins which were mainly involved in carbohydrate and protein metabolism, cell growth and replication, indicating that several developmental processes remain active in fruit bodies post-harvest. Proteins with antioxidant activities were identified, indicating the contribution of proteins to the antioxidant properties of L. edodes extracts. Antibacterial assays also reveal the activity of a serine protease inhibitor that strongly accumulates in the post-harvest fruit body grown on oak logs. Overall, this study contributes to the understanding of the impact of the log cultivation method on the production of Shiitake mushrooms richest in high-value bioactive compounds.

Design and construction of a wood-based modified yam pounder machine

This study focused on the design and construction of a wood-based modified yam pounder machine. The high cost of producing yam pounder machine using stainless steel and other metals poses great challenges in terms of efficiency and affordability. In this study, a yam pounder was produced from hardwood obtained from Oak tree which is a locally sourced material with a view to eliminating the tedious and laborious process of preparing pounded yam. The hardwood log of 220 mm long was turned to a diameter of 240 mm using wood lathe machine. Other components were machined to their appropriate sizes based on designed specification before assembling. The designed yam pounder was used to pound 1.034 kg of cooked white yam for three minutes; the same were carried out with the existing yam pounder for three minutes under the same condition. The results obtained from performance tests showed that there was no yam seed from the designed yam pounder but there were few yam seeds in the existing yam pounder. This showed that the designed yam pounder pounds better than the existing one.

The Effect of Kerf Thickness on Hardwood Log Recovery

Abstract When sawing a log into lumber or other products, the saw blade removes material to separate the wood fibers between the resulting two parts, a loss of material that is commonly referred to as saw kerf. Thicker kerfs result in greater waste and less material available to produce lumber. Over the past decades, with the advancement of materials and technology, saw blade thickness has decreased. However, the reduction in material loss owing to a reduction in saw kerf may not always translate into a statistically significant increase in lumber product recovery. In this study, we explored the effect of saw kerf thickness on lumber recovery for a range of hardwood log diameters using the US Forest Service's Log Recovery Analysis Tool (LORCAT) sawmill simulation tool. Results indicate that the recovery gains realized depend upon the log diameters sawn, the lumber target thickness, and the change (reduction) in the thickness of the saw kerf.

An Analysis of U.S. Hardwood Log Exports from 1990 to 2021

Abstract In 1990, the major destinations for hardwood logs exported by the United Sates were Europe, Canada, and three East Asian markets: Japan, Taiwan, and Korea. From 1990 to 2005, the volume of hardwood logs exported to Canada increased by 402 percent. During this period, another East Asian log market developed, consisting of China, Hong Kong, and Vietnam (CHV). While increased Canadian exports were an apparent result of increased U.S. bilateral trade with Canada, the development of the CHV market was associated with increased U.S. furniture imports from that region. The volume of U.S. log exports worldwide peaked in 2005, and the value of log exports peaked in 2007. Exports to all regions declined in 2009. After 2009, exports to CHV increased and surpassed shipments to Canada in 2014. In the past decade, much of the increase in exports to CHV appears to be the result of demand within China. Recently, these exports have been affected by trade disputes and the COVID-19 pandemic. For most of the study period, the dominant log export species were white oak, red oak, maple, or cherry in terms of value. Since 2018, walnut has become the most important log export species (value basis) as a result of increased shipments to China.

A decision-support system to assist forest industry planning and investment when data are scarce: the case of hardwood veneering in subtropical eastern Australia

ABSTRACT An aspatial mathematical model has been developed to simultaneously support log processing investment decisions with respect to processing scale, facility location and log procurement when data are scarce. A key design principle was to make the model suitable for use by industry. The objective function maximises gross margins per hour of log processing time, and the model accounts for potential processing efficiencies with larger-diameter logs. To support log procurement decisions, the model estimates mill-delivered log costs at which a log procurement officer should be indifferent between purchasing alternative log types. The utility of the model is demonstrated with an application to rotary veneer processing of hardwood logs in subtropical eastern Australia. Complex interactions between processing scale, facility location and log procurement strategies were revealed by substantial differences in gross margins between modelled scenarios. Log procurement decisions were found to have the greatest potential impact on gross margins, followed by facility location and processing scale. The model highlighted that substantially higher returns can be earned from optimal log procurement strategies relative to approaches that either minimise log costs, maximise product recovery or do not differentiate between log types and simply utilise all available log volume.

Hardwood Log Grading in the United States—Part III: An Assessment of the Current Status of Log Grading in the Hardwood Industry

Abstract This article documents how the hardwood industry, in the absence of a standardized, industry-wide log grading system, has gone about grading and scaling hardwood logs by surveying mills, primarily in the Appalachian region. In total, 135 surveys were completed by respondents and returned via mail, with only 110 of those surveys considered usable for further analysis, after a thorough review of the individual surveys. Survey responses were grouped around annual production level, with three defined levels; ≤2.5 million board feet (MMBF), >2.5 and ≤8.0 MMBF, and >8.0 MMBF. Responding mills used some variation of a log grading system based on the number of clear faces on the log and the small end diameter of the log. The most common log rule used by mills in this study was the Doyle log rule, with over 75 percent using Doyle for scaling logs. Nearly 90 percent of all mills sampled graded logs without rolling the log to examine all four sides/faces. Half of all the sawmills surveyed pay the same price per thousand board feet (MBF) for butt logs and uppers. When asked if they would support the development of a standard log grading system, about two-thirds of the respondents (66%) indicated they would indeed support a standardized system for Appalachian hardwoods. These findings can help guide the development of a set of log grading standards for buyers and sellers in the Appalachian region and other parts of the world where hardwood lumber is produced.

Reliability of photo-optical measurements of log stack gross volume

In terms of assessing economic impact, one of the most important elements in the wood supply chain is the measurement of round wood. Besides the one-by-one measurement of logs, logs are often measured when stacked at the forest road. The gross stacked volume includes the volume of the wood, bark and airspace and is widely used for industrial wood assortments. The increasing international attention given to photo-optical measurement systems for portable devices is due to their simplicity of use and efficiency. The aim of this study was to compare the gross volumes of hardwood log stacks measured using one widespread photo-optical app with two manual section-wise volume estimations of log stacks based on the German framework agreement for timber trade (RVR). The manual volume estimations were done starting from the left (RVR) and right (RVR) sides of the log stacks. The results showed an average deviation of the photo-optical gross volume estimation in comparison to the manual estimation of –2.09% (RVR) and –3.66% (RVR) while the deviation between RVR and RVR was +2.54%. However, the log stack gross volume had a highly significant effect on the deviation and better accuracy with smaller deviation were reached for larger log stacks. Moreover, results indicated that the gross volume estimations of higher quality log stacks were closer for the three analyzed methods compared to estimations of poor-quality log stacks.leftrightleftrightleftright

Design of a Total Revenue Forecasting Tool to Estimate the Economic Output of Hardwood Logs

Abstract This article introduces a total revenue forecasting tool designed for calculating the economic output of visually graded hardwood lumber. The tool integrates Monte Carlo simulation from previous studies' data, providing a pseudoestimation of total board-feet based on log grades. The lumber output from different log groups is modeled using probability distributions for each lumber grade. The estimated volume output is multiplied by the respective price for each grade, leading to an expected amount of economic output for given log-grades. The tool was implemented using Microsoft Excel 2016 and Visual Basic. This work provides hardwood lumber producers with a valuable and simple tool to determine different scenarios of total income from each log, as established by the user with a statistical perspective. This total revenue forecasting tool provides the industry with a way to reduce waste and estimate their potential revenue by maximizing the interaction between the log yield's variables and providing the economic output of log, leading to an improvement of the economy of the hardwood market.

Evaluating internal condition of hardwood logs based on AR-minimum entropy deconvolution combined with wavelet based spectral kurtosis approach

Abstract The aim of this research was to explore the potential of acoustic impact test to evaluate the condition of hardwood logs in regard to internal decay, void, crack and defect ratio using an acoustic signal separation and enhancement algorithm. Longitudinal acoustic signals were obtained from 15 logs of four hardwood species through acoustic impact testing. The defect components were separated from the acoustic response signals and enhanced based on the autoregressive minimum entropy deconvolution (AR-MED) method, and from which the kurtosis was derived and used as the global feature parameter for evaluating the internal condition of logs. Compared with the acoustic velocity obtained directly from the original signal, the kurtosis was deemed to be a more powerful predictor of log defect ratio with higher coefficient of determination (R 2 = 0.89) and was not affected by log species. To identify the type of defects, a complex Morlet wavelet-based spectral kurtosis (SK) method was proposed. The research results indicated that the SK can not only determine the type and primary and secondary major defects, but also be able to identify those that were not detectable by global acoustic parameters.

Experiments with the Purpose of Expanding the Loading Capacity of Standard Construction Grapples

A grapple is a device that includes at least one gripping arrangement. The gripping arrangement is configured to grip and traverse objects so as to reach a desired location on site and to anchor it, therefore allowing the work to be carried out. [1] A method for controlling the fill volume of a grapple, such as a bulk-material crane grapple which includes at least one hoist-and-closure unit, may include adjusting the fill volume of the grapple is during the grapple closure process by adjusting/controlling the grapple hoist height. The grapple hoist speed and/or grapple hoist height may be the controlling parameter for the adjustment of the fill volume of the grapple. [2]Grapples geometric configuration is established by calculating the useful load mass. In the experiments performed in the present paper the load mass was 3000 kg. In exploitation, in cases where relatively low density materials, if compared to standard materials, are being moved/processed, changes to the volume capacity must be done; [3] changes that need to be correlated with the new materials and the exploitation conditions.The tractor attachment is a grapple assembly, and the grapple assembly kit includes a mounting assembly, a plurality of clamping units, and a plurality of support units. [4] A connection system for coupling an claw to a work vehicle includes a receiver assembly that needs to be implement and configured to a connector assembly of an arm of the work vehicle. [5]The solution developed by the authors consists in prolonging and consolidating the active elements of the grapple, by equipping it with additional elements that take and process load tensions, in the present case hard wood logs; and a consolidation and protection system that protects it from wear, that mostly appears when the hook crane repeatedly hits the ground in order to collect the deposited logs.The additional elements for handling and processing logs are made out of low alloyed steel, thus by configuring the tips we assure the good gliding of processed materials on the active/used surfaces. The self-protection system to wear is made out of boron micro-alloyed steel sheets that have hardness values up to 500 HB. Joining the grapple ensemble with specialized elements was performed through welding.

Sustainable Timber Trade: A Study on Discrepancies in Chinese Logs and Lumber Trade Statistics

Discrepancies in trade statistics can be normal or benign and attributed to a wide variety of unintentional factors, or in some instances within the timber products sector, such discrepancies can be associated with “systemic” factors that distort trade statistics, including (i) measurement and shipment issues, (ii) misreporting of product volumes, (iii) misclassification of timber product types, and (iv) government regulations concerned about trade. This study measured trade discrepancies in logs and lumber trade statistics for China and its trading partner countries from 2002 to 2018 using a time-lagged function, based on the customs data available from Global Trade Information Services (GTIS), with the aim of exploring a more nuanced understanding of trade discrepancies and their “systemic” factors. The results showed that the range of overall discrepancies in logs and lumber trade statistics shrunk over time, from [−0.069, 1.207] in 2002–2007 to [−0.120, 0.408] in 2013–2018. The larger trade flows of logs and lumber from Russia, New Zealand, and the U.S. (each above 10% of total China’s import) showed small trade statistics discrepancy ratios, which were less than ± 0.06. However, trade discrepancies still remained large at the disaggregated level, and significant differences of trade discrepancies between tropical and non-tropical countries. The range of trade discrepancies in hardwood logs increased from 2002 to 2018 and appeared to be attributed to misclassification and misreporting in tropical countries such as Indonesia, the Philippines, Thailand, and Ghana. However, these countries’ trade flows are becoming relatively minor over time. Government policies are suggested to play an important role in influencing both the occurrence and resolution of trade discrepancies.