Relating Quantity, Quality, and Value of Lumber to Planting Density for Loblolly Pine Plantations

This report presents results of a lumber recovery study from a set of loblolly pine spacing trial plots established at 1210 trees ac(-1), 681 trees ac(-1) and 302 trees ac(-1) densities on two coastal plain sites, one in Virginia and the other in North Carolina. The impact of initial planting density on quantity, quality, and value of lumber recovered at age 27 was determined. There was a significant, negative relationship between planting density and total mill run bd ft production by green chain tally with the 302 trees ac(-1) density producing on average 161% more bd ft of lumber than the 1210 trees ac(-1) density and 40% more than the 681 trees ac(-1) density. For the butt log, no significant difference due to initial spacing was found in the proportion of bd ft with a visual grade of 2 or better and the proportion receiving a grade of 3 or less by green chain. When the value of the lumber was determined by applying assumed prices to the bd ft ac(-1) amounts by dimension and grade, including value attributed to lumber obtained from upper logs, the values ranged from $1194 ac(-1) for the 1210 trees ac(-1) planting density to $2934 ac(-1) for the 302 trees ac(-1) density. These differences were significant across the planting densities studied here. Managers can use the information when assessing the impact of initial planting density on quantity, quality and, hence, value of lumber from plantation-grown loblolly pine trees.