Research Report No. 30, A Guide for Timing Initial Tree Harvests in East Texas Loblolly and Slash Pine Plantations

In East Texas, there are approximately 3 million acres of loblolly ( Pinus taeda L. ) and slash ( Pinus elliottii Engelm. ) pine plantations. Most of these plantations, which represent about 25% of the forested area of East Texas, have been planted since 1970. As these planted trees age, East Texas foresters may be considering initial timber harvesting decisions for unthinned plantations. Often the timing of the harvests can be determined by considering combinations of economic and non-economic values, utilization standards and timber growth' factors. However, in some situations, it may be appropriate to ascertain the proper timing by considerihg only timber growth factors. ' Decision-making models that determine the optimum timing of timber operations by maximizing a measure of economic utility, such as present net worth, provide accurate and useful information to the plantation manager. In other models, useful decisions on timing timber operations can also be obtained only by considering the development of stand factors, such as yield per acre, basal area per acre, stand height growth and stand diameter growth. The purpose of this paper is to present observed patterns of unthinned planted loblolly and slash pine diameter development and survival trends in East Texas and, based on the patterns, recommend the timing of: • An initial (or intermediate) harvest to remove only some of the planted pine trees or• An initial (or final) harvest to remove all of the planted pine trees, while realizing that the growth patterns present in some unthinned East Texas pine plantations may suggest that no immediate timber harvests may be appropriate.