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

1998 ◽  
Vol 22 (1) ◽  
pp. 41-46 ◽  
Author(s):  
James B. Baker ◽  
Michael G. Shelton

Abstract Development of 86 intermediate and suppressed loblolly pine (Pinus taeda L.) trees, that had been recently released from overtopping pines and hardwoods, was monitored over a 15 yr period. The trees were growing in natural stands on good sites (site index = 90 ft at 50 yr) that had been recently cut to stocking levels ranging from 10 to 50%. At time of release, the trees averaged 26 yr in age, 4.8 in. in dbh, and 37 ft in height. The trees had averaged only 0.5 in. in dbh growth the 5 yr prior to release (0.1 in./yr). After 15 yr, the 77 surviving trees averaged 59 ft in height and 12.9 in. in dbh, increasing 21 ft in height and 8.1 in. in dbh. During the 15 yr period, crown dimensions of the trees increased markedly as well. On average, crown lengths increased 11 ft (from 16 to 27 ft); crown widths nearly tripled from 9 to 25 ft; and crown volumes increased 11 fold from 608 to 6,700 ft³. The majority of the trees had good form and would produce high-quality sawtimber. Satisfactory 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 10 to 50 yr. Responding trees rapidly expanded their crowns and accelerated in height and diameter growth. South. J. Appl. For. 22(1):41-46.

1983 ◽  
Vol 7 (1) ◽  
pp. 45-50 ◽  
Author(s):  
Paul A. Murphy ◽  
Robert M. Farrar

Abstract Equations are given to estimate current and projected sawtimber volumes and projected basal area of the sawtimber portion of uneven-aged loblolly-shortleaf (Pinus taeda L.-Pinus echinata Mill.) pine stands managed under the selection system. The independent variables are elapsed time, initial merchantable basal area, and the initial ratio of sawtimber basal area to merchantable basal area. The results should provide guidelines for the board-foot and cubic-foot production of sawtimber-sized trees in uneven-aged stands that occur on average sites (site index 90, loblolly pine) in the Coastal Plain.


1998 ◽  
Vol 22 (1) ◽  
pp. 35-40 ◽  
Author(s):  
James B. Baker ◽  
Michael G. Shelton

Abstract Two loblolly-shortleaf pine (Pinus taeda L.-P. echinata Mill.) stands were cut to stocking levels of 10, 20, 30, 40, and 50% to simulate recently cutover, understocked, uneven-aged stands. Number of trees ranged from 38 per acre for 10% stocking to 213 per acre for 50% stocking; comparable total basal areas were 4 and 16 ft²/ac, respectively. One stand was on a good site (site index = 90 ft at age 50), the other on a medium site (site index = 75 ft at age 50). As a rehabilitation treatment, all hardwoods 1 in. groundline diameter and larger were injected with a herbicide. At 2, 5, 10, and 15 yr after treatment, the stands were inventoried to determine: (1) rate at which the understocked stands recovered, and (2) minimum stocking levels required for successful rehabilitation. During 15 yr of rehabilitation, the understocked stands changed dramatically, and because of rapid growth of residual pines, stocking levels, basal areas, and tree volumes increasedmarkedly. Stands having at least 20% residual stocking and 5 ft²/ac of pine basal area reached an acceptable stocking level of 60% (based on number and size of trees), or 45 ft²/ac of basal area within 15 yr. Stands at this minimum stocking threshold produced 4,600 bd ft(Doyle)/ac of sawtimber volume on the good site and 3,000 bd ft/ac of sawtimber volume on the medium site during the 15 yr period. The study indicates that recently cutover, or damaged, understocked stands with at least 20% to 30% stocking or 5 to 10 ft²/ac of pine basal area can be rehabilitated to produce respectable sawtimber volumes. This management strategy provides a low-cost alternative to establishing a new stand at considerable cost to the landowner. South. J. Appl. For. 22(1):35-40.


1991 ◽  
Vol 15 (1) ◽  
pp. 10-17 ◽  
Author(s):  
James M. Guldin ◽  
Michael W. Fitzpatrick

Abstract Log grade, number of knots, and log volume of the first two logs, as well as form class of the butt log, were compared across three broad sawtimber categories among even-aged plantations, even-aged natural stands, and uneven-aged natural stands of loblolly pine (Pinus taeda L.) in Ashley County, AR. Trees from uneven-aged stands had butt logs of better log grade than even-aged plantations, particularly in the large sawtimber component where the average difference was half a log grade. Compared to even-aged natural stands, trees from uneven-aged stands had logs of comparable grade. Trees from even-aged natural stands produced butt logs of slightly better grade, but with greater taper and less volume per log, than trees from even-aged plantations. To produce high-grade loblolly pine sawtimber in the West Gulf region, natural stand management will suffice; plantation management may require supplemental quality intervention such as artificial pruning. South. J. Appl. For. 15(1):10-17.


1998 ◽  
Vol 22 (1) ◽  
pp. 53-59 ◽  
Author(s):  
James B. Baker ◽  
Michael G. Shelton

Abstract A 3- to 6-yr-old naturally regenerated even-aged loblolly pine (Pinus taeda L.) stand and a 5-yr-old loblolly pine plantation on good sites (SILob = 85 to 90 ft at 50 yr) were cut to density levels of 50, 90, 180, 270, and 360 seedlings and/or saplings/ac. Two pine release treatments (none and individual tree release with a herbicide) were applied to the natural stand, but were not imposed in the plantation because site preparation treatments were applied before planting. At 2, 5, and 10 yr after installation, plots were inventoried to determine: (1) the lowest threshold of seedling/sapling density that was feasible to manage, (2) the time required for poorly stocked seedling/sapling stands to reach an acceptable stocking level, and (3) whether release treatments would improve survival and growth of understocked, natural seedling/sapling stands. Results indicated that loblolly pine plantations on good sites having at least 180 trees/ac (30% stocking) reached an acceptable stocking level of 60% by age 10 and produced up to 1,500 ft³/ac (19 cd/ac) of merchantable volume by age 15. By this age, trees in plantations with 270 and 360 trees/ac displayed good form, but at densities of 180, 90, and 50 trees/ac the trees still retained large branches nearly to the ground. Natural stands having at least 180 trees/ac that were released from overtopping by hardwood at age 5 reached 60% stocking by age 15 but produced only 627 ft³/ac (8 cd/ac) of merchantable volume. When pines in the natural stand were not released, only plots with 360 trees/ac reached an acceptable 60% stocking level by age 15 but only produced 539 ft³/ac (7 cd/ac) of merchantable volume. The observed differences in recovery rates in the understocked pine stands principally reflected the levels of competing hardwoods. Results suggest that understocked, natural stands or plantations of pine seedlings/saplings with fewer than 180 trees/ac (less than 30% stocking), at age 5, should probably be liquidated and a new stand established unless the landowner is willing to sacrifice significant reductions in early volume production. South. J. Appl. For. 22(1)53-59.


1985 ◽  
Vol 9 (4) ◽  
pp. 247-249 ◽  
Author(s):  
H. L. Williston

Abstract Unthinned loblolly pine (Pinus taeda L.) planted near Abbeville, Mississippi in a creek bottom with a site index of 122 had a yield of 6,925 cubic feet per acre at age 26. Shortleaf pine (Pinus echinata Mill.) planted beside the loblolly pine had a site index of 108 and a yield of 4,120 cubic feet per acre.


Forests ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 935
Author(s):  
Mohammad Bataineh ◽  
Ethan Childs

The need for a comprehensive and mechanistic understanding of competition has never been more important as plants adapt to a changing environment and as forest management evolves to focus on maintaining and enhancing complexity. With the recent decline in shortleaf pine (Pinus echinata Mill.) land area, it is critical to determine the effects of competition on shortleaf pine and its performance against loblolly pine (Pinus taeda L.), the preferred planted replacement. We evaluate differences in shortleaf and loblolly pine 10 year mean basal area increment (BAI) and crown dimensions across a gradient of neighborhoods. Linear mixed-effects regression models were developed using BAI and several crown metrics as responses and crowding, competitor species abundance and identity, and initial size and species identity of focal tree as predictors. Crowding of focal trees negatively impacted BAI and crown size (p < 0.001, respectively). Although loblolly pine had three times higher BAI as compared to shortleaf pine within similar neighborhoods, BAI was variable, and the crowding effect did not differ between shortleaf and loblolly pine (p ranged from 0.51–0.99). Competitive impacts on focal trees did not differ by competitor identity (p ranged from 0.07–0.70). Distance-independent competition indices better explained the variation in BAI and horizontal crown metrics, while distance-dependent size ratios were more effective at evaluating vertical crown metrics. These findings highlight shortleaf pine competitive potential in mature, natural-origin stands and provide support for the restoration of pine–hardwood and hardwood–pine stratified mixtures as well as management of shortleaf pine at long rotations.


1987 ◽  
Vol 11 (4) ◽  
pp. 185-189 ◽  
Author(s):  
Ralph L. Amateis ◽  
Harold E. Burkhart

Abstract Stem analysis data were used to examine volume, height-dbh, form and taper relationships for loblolly pine (Pinus taeda L.) trees grown in unthinned old-field plantations, cutover-site plantations, and natural stands. Results showed significant differences in volume, height-dbh, tree form and taper relationships for loblolly pine grown in stands from these three origins. Thus, in order to accurately predict total and merchantable volumes as well as upper stem diameters and heights, forest managers should apply separate volume and taper equations for each stand class. South. J. Appl. For. 11(4):185-189.


1988 ◽  
Vol 12 (4) ◽  
pp. 275-280 ◽  
Author(s):  
Donald H. Marx ◽  
Charles E. Cordell ◽  
Alexander Clark

Abstract Loblolly pine (Pinus taeda L) seedlings with different initial amounts of Pisolithus tinctorius (Pt) ectomycorrhizae (Pt index 0, 27, 46, 68, or 88) were planted on a good-quality site (site index 90 ft at age 50) in southwest Georgia. After 8 years and crown closure, trees with Pt indices of 88 and 68 had significantly better survival and greater heights, diameters, volumes, and green weights per tree and per ac than nursery-run, control seedlings (Pt index 0). Volume and weight yields per ac were over 50% greater and volume and weight yields per tree were over 20% greater for trees in the Pt index 88 treatment than they were for control trees. A special statistical analysis indicated that average per ac volume was positively correlated with initial Pt index values larger than 58. Tree-ring analyses showed that trees with a Pt index of 88 had significantly greater annual basal area growth than controls during growing seasons with water deficits of 8 to 13 in. Annual growth did not differ when water deficits were greater or less than these amounts. After 8 years, Pt basidiocarps were present throughout the study site. Mycorrhizal treatment integrity may have been lost after 3 or 4 years. South. J. Appl. For. 12(4):275-280


1982 ◽  
Vol 6 (4) ◽  
pp. 215-217 ◽  
Author(s):  
G. L. Wheeler ◽  
F. M. Meade ◽  
M. W. Russell

Abstract A thinning and fertilizing study was established in an 11-year-old loblolly pine (Pinus taeda L.) plantation. Half of the plots were row thinned, removing 50 percent of the trees; plots were split and half were fertilized at a per acre rate of 100 pounds nitrogen, 50 pounds phosphorous and 50 pounds potassium. There was no response of height, d.b.h. or volume growth to fertilizer. Thinning increased diameter growth but decreased volume growth. The trees have shown exceptional growth. At age 17 the height was 49 feet, d.b.h. 7.3 inches and stocking 2,490 cubic feet on the thinned plots. The respective values for the unthinned plots were 48 feet, 6.7 inches, and 3,960 cubic feet.


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