Determining the Extent of damage in Snapped Southern Yellow Pine Trees with Acoustic Testing

Abstract

Abstract Salvage of downed timber following a windstorm allows recovery of management options for landowners and wood products for industry. Because wood volumes are large and logging, transportation, mill storage, and processing capacities are limited, avoiding the selection of logs with damage can conserve those resources. Visual damage indicators are typically used to select and differentiate products, but damaged logs are still delivered to mills. Following experimental tree winching in 2021 and a tornado in 2023, we assessed lengths of broken trees with a Fakopp microsecond timer. Using a recognized defect limit (10% deviation from the maximum acoustic velocity) about 80 percent of volume in broken tops could be recovered. Standard rules of thumb applied from the end of visible damage resulted in the recovery of about 50 percent of the volume with a relatively low defect rate (<10%). Applying bucking rules developed from acoustic measurements based on distance from snap might be easier to apply and increase recovery rates to over 70 percent of broken top volume.