Tracking Responsible Wood Sourcing Through Forensic Fiber Analysis

In a past post, we discussed forensic fiber analysis, a process by which investigators collect fibers as evidence to determine an individual’s involvement at a particular location. However, forensic fiber analysis can be used for applications beyond this, as it has recently become important for tracking down fraudulent logging practices.

ASTM D7612-10(2015) - Standard Practice for Categorizing Wood and Wood-Based Products According to Their Fiber Sources provides wood product manufacturers, distributors, and retailers with a system to convey the origin of wood fibers in their products to the consumer, demonstrating operation under a forest management system. The criteria differentiates wood products into categories based on the wood fiber tracing systems, forest certification, and other standards that apply to their production to demonstrate that the material comes from responsible sources.

However, the initial aspects of responsible sourcing are the duty of the local legislation where the forest clearing occurs. While professional foresters have been the leaders in developing and improving forest management processes in North America, the best practices are not followed in all parts of the world. Because of this, there is a possibility that some wood products have been falsely identified, and they might even come from endangered plant species.

Interest in testing wood has grown due to a revision made to the U.S. Lacey Act in 2008. The Lacey Act is a century old-law that bans the trafficking of illegal wildlife. The latest amendment to the federal law has widened its scope to include plants and plant products. This makes the trade of timber, paper, or any other plant-based product that was illegally harvested in another country a violation of federal law in the United States. Punishment depends on the violator’s knowledge of the product, but those unaware of the irresponsible source can still be prosecuted.

This has spawned different genetic testing processes, all of which make use of gene sequencing to uncover unique patterns in tree DNA that indicate the presence of a particular species. While DNA testing is by no means a new practice, having long played a role human criminal trials and the pursuit of wildlife traffickers, it is still new for forest conservation. Today, with the improved technology being readily available at lower costs, large-scale screening of wood, from forest to sawmill, can be done cheaply and with the statistical certainty that will hold up in a court of law.

However, fiber testing of wood has demonstrated that non-DNA approaches can also play an important role in the reliable sourcing of wood products. Fibers, the same long narrow objects that comprise hair and clothing, are found in hardwoods. In trees, the walls of fibers can be thick or thin, depending on the specific species from which they derive. In addition, fibers produced near the end of the growing period are thick-walled and tangentially flattened, so classifying the fiber’s features can provide a great deal of information on the wood’s origin.

Wood fiber testing involves a microscopic examination of the anatomy of a fiber sample to characterize and compare it with a known reference material to establish its species and point of origin. This can be especially challenging, as the wood can contain many different additives, binders, resins, or matrix materials, but these can also be detected through some forensics operations.

These forensic analyses also make use of the reaction that wood fibers have to particular chemicals to classify the species. This is very useful for determining the origin of paper, as it is also covered under the Lacey Act. In 2010, the World Resources Institute (WRI), used this method to help fiber test 32 imported paper products. Three of the products contained pulp from endangered ramin (Gonstylus) and mangrove trees.

Being able to track down the source of wood products and put any illegal logging operations to a halt is imperative. The laws and standard practices certifying the trade and use of wood materials exist for a reason. For example, many species of mangrove trees, such as those that were found in the WRI test, are endangered due to long-term overharvesting. This is a problem for more than just the mangroves, because the trees are the fundamental component of many vibrant ecosystems in different continents, not only serving as important nursery habitats for a variety of fish species, but also housing insects and even endangered mammals like the Bengal tiger. Any harm brought to the trees can severely affect the local animals and their environment.

Other Forensic Fiber Analysis Standards, covering the microscopic identification of cloth fibers, hairs, and other fibers, are available on the ANSI Webstore.