scholarly journals Rehabilitation of Understocked Loblolly-Shortleaf Pine Stands—IV. Natural and Planted Seedling/Sapling Stands

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.

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.


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.


1989 ◽  
Vol 13 (3) ◽  
pp. 132-139 ◽  
Author(s):  
James B. Baker

Abstract Plots in two uneven-aged loblolly-shortleaf pine (Pinus taeda L.-P. echinata Mill.) stands were cut back to stocking levels of approximately 10, 20, 30, 40, and 50% to simulate cutover, understocked stands. One stand was on a good site (SI = 90 ft at age 50), the other on a medium site(SI = 75 ft at age 50). As a rehabilitation treatment, all hardwoods 1-in. or larger in groundline diameter were injected with Tordon 101®. Two and 5 years later, the plots were reinventoried to determine stand growth and development. During the 5-year rehabilitation period the understockedstands changed dramatically, and because of the rapid growth of the pines left in the residual stands, stocking levels, basal areas, and tree volumes increased markedly. Average increases in stocking level, basal area, pulpwood, and sawlog volume were 40, 155, 160, and 355%, respectively,for the good site and 35, 110, 125, and 220% for the medium site. Projections of the time required for understocked stands to reach an acceptable stocking level of 60% (based on number and size of trees), or 45 ft² of basal area per acre, indicate that stands having at least 15 to 25%stocking, or 5 ft² of basal area per acre, can reach an acceptable stocking level in 15 years or less at a rehabilitation cost of $45 to $50 per acre. South. J. Appl. For. 13(3):132-139.


1998 ◽  
Vol 22 (1) ◽  
pp. 47-52 ◽  
Author(s):  
James B. Baker ◽  
Michael G. Shelton

Abstract Plots in an unmanaged loblolly-shortleaf pine (Pinus taeda L.-P. echinata Mill.) stand that had been cutover 15 yr previously were established to represent five stocking levels: 10, 20, 30, 40, and 50%. The stand was on a good site (site indexLob = 90 ft at 50 yr) and had uneven-aged character. Two competition control treatments (none and individual tree release using herbicide) were also assigned. Three, five, and nine years later, the plots were reinventoried to determine: (1) the rate at which the understocked stands recovered, (2) the minimum stocking level required for successful rehabilitation, and (3) the effects of release on pine growth. The pine release treatment did not enhance stand development during the 9 yr rehabilitation period, primarily because only 18% of the pines (representing 5% of total pine basal area) were overtopped by hardwoods and were thus in need of release. However, results suggest that stands having an initial stocking of 20 to 30%, or a total basal area of 10 to 15 ft²/ac, can reach an acceptable stocking (levels of 60% for stocking, 45 ft²/ac for basal area, and 2,500 bd ft(Doyle)/ac for sawlog volume) within 15 yr or less. South. J. Appl. For. 22(1):47-52.


2017 ◽  
Vol 47 (10) ◽  
pp. 1364-1371 ◽  
Author(s):  
Joshua C. Bradley ◽  
Rodney E. Will

Hybridization between shortleaf pine (Pinus echinata Mill.) and loblolly pine (Pinus taeda L.) has dramatically increased and may threaten the genetic integrity of shortleaf pine. Shortleaf pine is presumed to be more drought tolerant than loblolly pine, but the drought hardiness of the hybrid pine is not known. We determined biomass partitioning in response to water stress and measured whole-plant transpiration of shortleaf, loblolly, and hybrid pine seedlings. Water stress decreased total seedling biomass, increased biomass partitioning to foliage, and decreased biomass partitioning to coarse roots. Shortleaf pine seedlings partitioned more biomass to coarse roots than loblolly pine, and hybrid pine was intermediate between the parent species. We found no differences in the level of soil moisture at which seedlings of different species began to limit transpiration. Our results suggest that the transpiration response of shortleaf pine and hybrid pine is similar to that of loblolly pine when exposed to water stress. However, greater partitioning to coarse root may allow shortleaf and hybrid pines to better withstand drought due to greater potential belowground carbohydrate supply.


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.


Plant Disease ◽  
2002 ◽  
Vol 86 (7) ◽  
pp. 803-807 ◽  
Author(s):  
Stephen W. Fraedrich ◽  
Michelle M. Cram

A Longidorus species was consistently associated with patches of stunted and chlorotic loblolly pine seedlings at a forest-tree nursery in Georgia. Seedlings from affected areas had poorly developed root systems that lacked lateral and feeder roots. Longidorus population densities in composite soil samples from the margins of patches ranged from 9 to 67 nematodes per 100 cm3 of soil. In a growth chamber experiment, seedling root dry weight decreased with respect to the initial Longidorus dose as well as the final Longidorus populations in containers. The dry root weight of seedlings were 0.117, 0.090, 0.066, and 0.065 g in containers initially infested with 0, 50, 100, and 200 Longidorus, respectively. Lateral and fine roots were lacking on seedlings at the highest doses. Populations of Longidorus increased in all containers during the experiment. Damage to loblolly pine seedlings caused by Longidorus is a previously undescribed problem in southern pine nurseries. Proper diagnosis of the problem by nematode testing laboratories may require the use of extraction techniques specific for larger nematodes such as Longidorus.


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.


2000 ◽  
Vol 24 (2) ◽  
pp. 112-120 ◽  
Author(s):  
Michael M. Huebschmann ◽  
Lawrence R. Gering ◽  
Thomas B. Lynch ◽  
Onesphore Bitoki ◽  
Paul A. Murphy

Abstract A system of equations modeling the growth and development of uneven-aged shortleaf pine (Pinus echinata Mill.) stands is described. The prediction system consists of two main components: (1) a distance-independent, individual-tree simulator containing equations that forecast ingrowth, basal-area growth, probability of survival, total and merchantable heights, and total and merchantable volumes and weights of shortleaf pine trees; and (2) stand-level equations that predict hardwood ingrowth, basal-area growth, and mortality. These equations were combined into a computer simulation program that forecasts future states of uneven-aged shortleaf pine stands. Based on comparisons of observed and predicted stand conditions in shortleaf pine permanent forest inventory plots and examination of the growth patterns of hypothetical stands, the simulator makes acceptable forecasts of stand attributes. South. J. Appl. For. 24(2):112-120.


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