Abstract <p>Plantation forests in the southeastern United States are dominated by loblolly pine (<i>Pinus taeda</i> L.) whose wood is used to supply the lumber, composite, pellet, and pulp and paper industries; processing of this timber affords bark as a major byproduct. To date, information is limited regarding the variation of loblolly pine bark properties with relative tree height and how these trends vary with physiographic region. For this study, 139 stands across the natural range of loblolly pine were destructively sampled with three trees felled from each stand. Bark properties, specific gravity (SG), moisture content (MC), green mass (kg m⁻³), and percent (%) bark were determined from cross-sectional disks collected at multiple heights along the stem of each sampled tree. Values for bark MC and green mass increased with increasing height. Bark SG increased from the stump to a maximum at approximately 40% relative height before decreasing, whereas percent bark decreased to 40% relative height before increasing. While the trends in bark properties by relative height were consistent across all regions, significant differences by region were observed at some heights. Improved knowledge of bark properties will assist in efforts to valorize pine bark and refine calculations of carbon sequestered in it.</p> Study Implications <p>Information regarding variation in bark properties (specific gravity (SG), moisture content (MC), green mass (kg m⁻³), and percent (%) with tree relative height and physiographic region is provided for loblolly pine, a species that dominates plantation forests in the southeastern United States. Assessments provided herein are particularly relevant to refining calculations of carbon sequestered in one of the world’s most important carbon sinks, plantation loblolly pine growing across the southeastern US, with the bark being a significant factor both in standing forests and as a residue generated by the forest products industry sector.</p>