Natural Resources Conservation Service Technical Forestry Note TX-FS-12-6 Pre-commercial thinning – Benefits/Costs?

Pre-commercial thinning is a thinning method performed prior to trees reaching merchantable size, typically around 4.5 inches dbh (diameter at breast height measured at 4.5 ft. above the ground). The objective of a pre-commercial thinning is to release some trees in overstocked stands by reducing densities to prevent stagnation and increase the growth of the remaining trees. Many southern pine species regenerate by producing a great deal of seed, resulting in thousands of seedlings per acre. Loblolly pine, for example, can be a prolific seed producer under ideal conditions. Natural regeneration practices in even-aged systems through seed-tree or shelterwood methods often results in extreme overstocked conditions that, left untreated, can stagnate growth and lengthen rotation ages (Mann and Lohrey 1974).