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CSI Trees: Solving Timber Theft Crime with DNA

This is a past event.

Friday, October 29, 2021 at 1:30pm to 2:30pm

Virtual Event

Illegal logging is a worldwide problem that degrades ecosystems, incurs law enforcement costs, and creates market disadvantages for legal forest products. In the Pacific Northwest, bigleaf maple (Acer macrophyllum Pursh) is the primary target for “timber poaching”, or the illegal harvest of high-value trees that are used in musical instruments or fine furniture. In August 2018, a group of people accidentally started a wildfire in the Olympic National Forest (Washington state) while illegally poaching bigleaf maple trees. The resulting “Maple Fire” burned 3,000 acres and cost nearly $4M to contain. In their post-fire investigation, US Forest Service law enforcement hypothesized that the illegally harvested maple wood was sold to a mill in Tumwater, WA, even though defendants claimed the wood derived from legally-harvested trees on private land. Using a 133 single nucleotide polymorphism (SNP) genetic assay, US Forest Service geneticists determined that 225 wood blocks tested derived from 16 source trees; 86 of these blocks derived from three illegally harvested trees on the Olympic National Forest. DNA analysis showed that the probability of a coincidental match was less than one in one undecillion for each of the source trees. At trial, defendants were found guilty of all counts related to illegal logging (although they were acquitted on charges related to setting fire). This trial sets an important precedent, as it represents the first introduction of tree DNA evidence in a federal criminal trial. The abundance of genomic data in trees makes it increasingly possible to track illegally harvested wood, predict the geographic origin of wood, and track individual tree-derived evidence (e.g., leaves, needles, seeds) in human criminal cases.

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