Research Brief #14

A Comparison of Juvenile Wood and Mature Wood Properties in the Four Major Southern Pines
(La Tech FPL-1.1)
Louisiana Forest Products Development Center
Louisiana State University
Baton Rouge, LA

Research Objectives

Juvenile wood (JW) properties are generally inferior to mature wood (MW) properties from the same tree. The purpose of this project is to provide a better understanding of the relationships between age and physical, anatomical, and mechanical properties of JW and MW in plantation-grown loblolly, longleaf, shortleaf, and slash pines on the same site at the same age

Synopsis of Results

An evaluation of JW versus MW mechanical properties, modulus of elasticity (MOE) and modulus of rupture (MOR), has been completed. Neither MOE nor MOR differed significantly among the four species when grown to the same age on a wet, dry, and intermediate soil. MW MOE and MOR were higher than JW for all species. MW MOE averaged two times greater than that of JW and MW MOR averaged 1.5 tunes greater. Specific gravity of MW did not differ significantly among species

Progress

The results of the comparison of JW and MW MOE and MOR were presented at the Annual Meeting of the Forest Products Society in Portland, ME, June 1994. Work is continuing on growth rate and fiber length measurement. Changes in fiber length and specific gravity with age will be used to determine the juvenility period of the four species. Summarization of this data for loblolly pine is nearing completion.

Researchers

Mark D. Gibson, Associate Professor, Wood Utilization
George A. Grozditis, Research Associate
Louisiana Forest Products Laboratory
Louisiana Tech University
Ruston, Louisiana

Target Group

Wood products manufacturers interested in wood quality and its effect on their processes and forest resource managers.