Rehabilitation of Understocked Loblolly-Shortleaf Pine Stands—II. Development of Intermediate and Suppressed Trees Following Release in Natural Stands

Development of86 intermediate and suppressed lohlolly pine (Pinus taeda L.) trees, that had been recent!\. releusedfrorn overtopping pines and hurd~~ood.~, was monitored over a 15 yr period. The trees were growing in nutural stands on good sites (sire index = 9Oft at 50 yr) thut had been recently cud to stocking levels ranging,frorn 10 to 50%. At time of release, the trees averaged 26 yr in age, 4.8 in. in dhh, and 37ft in height. The trees had averaged only 0.5 in. in dhh growth the 5 yr prior to release (0. I in.lyr). After 15yr. rhe 77surviving trees averaged 59ft in height und 12.9 in. in dbh, increasing 21,ft in height and 8. I in. in dbh. During the 15 yrperiod, crown dimensions of rhe trees increased markedly as well. On average, crown lengths increased I I ft (fram 16 to 27,fi); crown widths nearly tripled,from 9 to 2.5,ft; and crown volumes increased I1 foldfrorn 608 to 6,700,p'. The majority qfrhe trees hadgooctforrn and wouldproduce high-quality sawfirnher. Sutisfactov response to release was best predicted by initial dbh and live-crown ratio. Results of the study suggest that trees with at least a 20% live-crown ratio should satisfactorily respond to release even though they had developed in lower crown positions of,fully stocked uneven-aged stands for IO toS0yr. Responding trees rupidlyexpanded theircrownsandaccelerured in heighranddiumetergrowth. South. J. Appl. For. 22(1):41-46.