Whole-Stand Models: Loblolly and Slash Pine Plantations

A new compatible whole-stand growth and yield model to predict total tree cubic-foot volume per acre yield (outside and inside-bark) was developed for unmanaged loblolly pine (Pinus taeda) and slash pine (Pinus elliottii) plantations in east Texas. This model was compared to the non- compatible whole-stand model of Lenhart (1996) and the Lenhart (1996) model refit to current data. For the two species, all three models were evaluated with independent observed data. The model developed in this study out-performed both Lenhart models in prediction of future yield and basal area per acre for all age classes combined and by five-year age classes. The Lenhart models consistently over-estimated yield and basal area per acre. All three models predicted surviving trees per acre similarly. An example is also provided to show users how to use the new whole-stand model. An ETTPRP report was published in 2010 which provides updates to the coefficient values in the 2009 SJAF paper, a new survival equation (which includes site index) as well as new arithmetic mean diameter equation

Modeling Thinning in East Texas Loblolly and Slash Pine Plantations

A new thinning model was proposed for loblolly pine (Pinus taeda L.) and slash pine (P. elliottii Engelm.) plantations in east Texas. The new model follows the index of suppression methodology introduced by Pienaar (1979). It was implemented in a new whole stand growth model for loblolly and slash pine plantations in east Texas (Coble 2009). The new thinning model performed similarly to existing Pienaar-type models for east Texas and the Southeastern United States across a range of site quality. The predicted basal area development consistently approached the unthinned counterpart, which is consistent with results from other studies. The new thinning model should be fully tested when empirical data become available. In the meantime, it can be used to model thinned loblolly and slash pine plantations in east Texas ranging in age from 5 to 40 years

Modified Stand Table Projection Models

Four methodologies to project future trees per acre by diameter class were compared to develop a new modified stand table projection growth model for unmanaged loblolly (Pinus taeda L.) and slash pine (Pinus elliottii Engelm.) plantations in east Texas. The new models were fit to 92,882 observations from 153 permanent plots located in loblolly pine plantations and 33,792 observations from 71 permanent plots located in slash pine plantations throughout east Texas. The new models were validated with 12,750 observations from 22 permanent plots and 3,724 observations from nine permanent plots located in loblolly and slash pine plantations, respectively. The validation data were used to select between the four methodologies. The results indicated that the new model based on the methodology of Cao and Baldwin (1999) produced the best results, based on error indexes calculated for trees per acre and basal area per acre at the stand table and diameter class levels across a range of projection lengths. We recommend that this new model be used by forest managers for projecting stand tables in east Texas loblolly and slash pine plantations. An example is also provided to show users how to use the new modified stand table projection model

A new whole-stand model for unmanaged loblolly and slash pine plantations in east Texas

A new compatible whole-stand growth-and-yield model to predict total tree cubic-foot volume per acre yield (outside and inside bark) was developed for unmanaged loblolly pine (Pinus taeda) and slash pine (Pinus elliottii) plantations in East Texas. This model was compared with the noncompatible whole-stand model of Lenhart (Lenhart, 1996, Total and partial stand-level yield prediction for loblolly and slash pine plantations in east Texas, South. J. Appl. For. 20(1):36–41) and the Lenhart (1996) model refit to current data. For the two species, all three models were evaluated with independent observed data. The model developed in this study outperformed both Lenhart models in prediction of future yield and basal area per acre for all age classes combined and by 5-year age classes. The Lenhart models consistently overestimated yield and basal area per acre. All three models predicted surviving trees per acre similarly. An example is also provided to show users how to use the new whole-stand model

Project Report No. 68, Observed Growth and Yield of Loblolly Pine Plantations in East Texas

Forestland in east Texas occupies about 12.1 million acres with 2.9 million acres (24%) classified as pine plantations on private land. Pine plantations are typically managed to produce timber, so information is needed to make informed management decisions. Growth is one piece of information that managers often rely upon in their decision making process

Project Report No. 69, Observed Growth and Yield of Loblolly and Slash Pine Plantations in East Texas

Forestland in East Texas is an estimated 12.1 million acres, with approximately 2.9 million acres (24%) classified as pine plantations on private land. Because pine plantations are typically managed for timber production, information regarding tree growth is needed to make informed management decisions. An understanding of how growth factors such as tree volume, diameter, height and basal area are affected by site index, trees per acre and age in East Texas enables plantation managers to make the management decisions necessary to maximize timber production

Effects of First Thinning on Growth of Loblolly Pine Plantations in the West Coastal Plain

The purpose of this research is to analyze thinning response in basal area and height growth of residual loblolly pine trees growing in plantations located in the West Gulf Coastal Plain. Thinning is a well-known silvicultural practice that increases the growing space available to desirable trees by removing competing trees

Compatible Cubic-Foot Stem Volume and Upper-Stem Diameter Equations for Semi-intensive Plantation Grown Loblolly Pine Trees in East Texas

The Max-Burkhart taper equation was used to develop compatible taper and volume equations for semi-intensive plantation grown loblolly pine (Pinus taeda L.) trees in East Texas. Semi-intensive plantations in East Texas are characterized by some form of mechanical site preparation, a burn, possibly chemical weed control, improved seedlings if planted after 1985, and, possibly, a midrotation thinning and/or fertilization. The equations in this study were compared with those of Lenhart et al. [Lenhart, J.D., T.L. Hackett, C.J. Laman, T.J. Wiswell, and J.A. Blackard. 1987. Tree content and taper functions for loblolly and slash pine trees planted on non-old field in east Texas. South J. Appl. For. 10(2)109 –112.] and Baldwin and Feduccia [Baldwin, V.C. Jr., and D.P. Feduccia. 1991. Compatible tree-volume and upper-stem diameter equations for loblolly and slash pines in the West Gulf Region. South. J. Appl. For. 10(2)109 –112.] using independent data. The new equations ranked first (sum of ranks 9) in terms of percent bias and percent SEE for inside-bark predictions of upper-stem diameters and cubic-foot volumes, while the Lenhart et al. [Lenhart, J.D., T.L. Hackett, C.J. Laman, T.J. Wiswell, and J.A. Blackard. 1987. Tree content and taper functions for loblolly and slash pine trees planted on non-old field in east Texas. South J. Appl. For. 10(2)109 –112.] ranked second (sum of ranks 17) and Baldwin and Feduccia [Baldwin, V.C. Jr., and D.P. Feduccia. 1991. Compatible tree-volume and upper-stem diameter equations for loblolly and slash pines in the West Gulf Region. South. J. Appl. For. 10(2)109 –112.] ranked third (sum of ranks 22). For outside-bark predictions of volumes and diameters, Baldwin and Feduccia [Baldwin, V.C. Jr., and D.P. Feduccia. 1991. Compatible tree-volume and upper-stem diameter equations for loblolly and slash pines in the West Gulf Region. South. J. Appl. For. 10(2)109 –112.] ranked first (sum of ranks 12), while the new equations ranked a close second (sum of ranks 13) and Lenhart et al. [Lenhart, J.D., T.L. Hackett, C.J. Laman, T.J. Wiswell, and J.A. Blackard. 1987. Tree content and taper functions for loblolly and slash pine trees planted on non-old field in east Texas. South J. Appl. For. 10(2)109 –112.] ranked third (sum of ranks 20). We recommend using the new equations for loblolly pine trees up to a 16-in. dbh and provide examples to illustrate their use

Relationships Between Habitat and Snag Characteristics and the Reproductive Success of the Brown-headed Nuthatch (Sitta pusilla) in Eastern Texas.

Habitat use and reproductive success of the Brown-headed Nuthatch (Sitta pusilla Latham) were studied in East Texas during the 2001-2002 breeding seasons. We compared nest cavity selection at used and randomly selected non-used areas. Height of nest trees, midstory density, and percent leaf litter were negatively correlated with nest site selection. Brown-headed Nuthatches showed a strong preference for short snags; yet placed their nest cavity entrances near the top ofthe snags. While nuthatches may be selecting for habitats with little or no midstory density, percent of leaf litter in the nest sites is most likely the consequence of frequent burning. No significant differences among habitat variables and snag characteristics were found between successful and failed nest cavities. Additionally, no habitat variables were correlated with the number of chicks fledged per nest. Predation was the major cause of nest failure in this study