Effects of Alternative Thinning Regimes and Prescribed Burning in Natural, Even-Aged Loblolly-Shortleaf Pine Stands: 25Year Results

In southeastern Arkansas, pine growth was monitored for 19 yr after mechanically strip thinning a dense, naturally regenerated, even-aged stand of Gyr-old loblolly pines (Pinus taeda L.) and shortleafpines (P. echinata Mill.) that averaged 16,600 stems/UC. Prescribed winter burns were conducted biennial ly between ages 9 and 20 yr and at 24 yr . Commercial th innings during the 17th and 23rd growing seasons le f t a res idual s tocking of e i ther SSf$/ac or 200 crop trees/at (7.5ft2/ac) in merchantable-sized (>3.5 in. dbh)pines on plots that wereprecommercial ly thinnedand on plots that were not . Precommercial thinning enhanced pine growth in dbh and sawlog volume through 25 yr. Because of increased sawlog production, present net value averaged highest on plots that were precommercial ly thinned at age 6 then commercial ly thinned during the 17th yr to 200 crop trees/at and during the 23rd yr to 7.5 ft2/ac. In the year following prescribed winter burns, both dbh growth and volume growth were reduced by about one-hal f when crown scorch was 75%. South. J. Appl. For. 27(1):18-29.