scholarly journals A New Site Index Model for Intensively Managed Loblolly Pine (Pinus taeda) Plantations in the West Gulf Coastal Plain

2019 ◽  
Author(s):  
Kynda R Trim ◽  
Dean W Coble ◽  
Yuhui Weng ◽  
Jeremy P Stovall ◽  
I-Kuai Hung
Keyword(s):  
Pinus Taeda ◽  
Loblolly Pine ◽  
Coastal Plain ◽  
Site Index ◽  
The United States ◽  
Pine Plantations ◽  
Permanent Plots ◽  
Gulf Coastal Plain ◽  
The West ◽  
Intensively Managed

Abstract Site index (SI) estimation for loblolly pine (Pinus taeda L.) plantations is important for the successful management of this important commercial tree species in the West Gulf Coastal Plain of the United States. This study evaluated various SI models for intensively managed loblolly plantations in the West Gulf Coastal Plain using data collected from permanent plots installed in intensively managed loblolly pine plantations across east Texas and western Louisiana. Six commonly used SI models (Cieszewski GADA model, both Chapman-Richards ADA and GADA models, both Schumacher ADA and GADA models, and McDill-Amateis GADA model) were fit to the data and compared. The Chapman-Richards GADA model and the McDill-Amateis GADA model were similar and best in their fit statistics. These two models were further compared to the existing models (Diéguez-Aranda et al. 2006 (DA2006), Coble and Lee 2010 (CL2010)) commonly used in the region. Both the Chapman-Richards GADA and the McDill-Amateis GADA models consistently predicted greater heights up to age 25 than the models of DA2006 and CL2010, with larger height differences for the higher quality sites, but predicted shorter heights thereafter. Ultimately, the McDill-Amateis GADA model was chosen as the best model for its consistency in predicting reasonable heights extrapolated beyond the range of the data. Foresters can use this model to make more informed silvicultural prescriptions for intensively managed loblolly pine plantations in the West Gulf Coastal Plain.

Predicting Stand Attributes of Loblolly Pine in West Gulf Coastal Plain Using Gradient Boosting and Random Forests

2020 ◽  
Author(s):  
Xiongwei Lou ◽  
Yuhui Weng ◽  
Luming Fang ◽  
HL Gao ◽  
Jason Grogan ◽  
...  
Keyword(s):  
Loblolly Pine ◽  
Random Forests ◽  
Coastal Plain ◽  
Mean Squared Error ◽  
Pine Plantations ◽  
Machine Learning Techniques ◽  
Coefficient Of Determination ◽  
Gradient Boosting ◽  
Gulf Coastal Plain ◽  
Intensively Managed

Two machine-learning techniques, gradient boosting (GB) and random forests (RF), were used to predict stand mean height (HT), trees per hectare (Tree ha-1) and basal area per hectare (BA ha-1) based on datasets collected from extensively- and intensively-managed loblolly pine plantations in the West Gulf Coastal Plain region. Models were evaluated using coefficient of determination (R2), bias and root mean squared error (RMSE) by applying models to independent dataset and then compared to the model (Coble et al. 2017) currently being used in the region. For extensively-managed plantations, the GB models had less bias, larger R2 and smaller RMSE than RF and HT model was the best, followed by those of Tree ha-1 and BA ha-1. Even for BA ha-1, the GB model had R2 over 0.83. GB and RF models outperformed the Coble et al. (2017); differences were notable for HT and Tree ha-1, but significant for BA ha-1. For intensively-managed plantations, GB and RF were similarly great in predicting HT and Tree ha-1, but GB outperformed RF in predicting BA ha-1. We recommend the use of GB models to predict quantitative information required for managing loblolly pine plantations in the region.

Modeling the longitudinal variation in wood specific gravity of planted loblolly pine (Pinus taeda) in the United States

2010 ◽  
Vol 40 (12) ◽  
pp. 2439-2451 ◽  
Author(s):  
F. Antony ◽  
L. R. Schimleck ◽  
R. F. Daniels ◽  
A. Clark ◽  
D. B. Hall
Keyword(s):  
United States ◽  
Specific Gravity ◽  
Pinus Taeda ◽  
Loblolly Pine ◽  
Coastal Plain ◽  
The United States ◽  
Atlantic Coastal Plain ◽  
Quadratic Model ◽  
Gulf Coastal Plain ◽  
Atlantic Coastal

Loblolly pine (Pinus taeda L.) is a major plantation species grown in the southern United States, producing wood having a multitude of uses including pulp and lumber production. Specific gravity (SG) is an important property used to measure the quality of wood produced, and it varies regionally and within the tree with height and radius. SG at different height levels was measured from 407 trees representing 135 plantations across the natural range of loblolly pine. A three-segment quadratic model and a semiparametric model were proposed to explain the vertical and regional variations in SG. Both models were in agreement that a stem can be divided into three segments based on the vertical variation in SG. Based on the fitted models, the mean trend in SG of trees from the southern Atlantic Coastal Plain and Gulf Coastal Plain was observed to be higher than in other physiographical regions (Upper Coastal Plain, Hilly Coastal Plain, northern Atlantic Coastal Plain, and Piedmont). Maps showing the regional variation in disk SG at a specified height were also developed. Maps indicated that the stands in the southern Atlantic Coastal Plain and Gulf Coastal Plain have the highest SG at a given height level.

Site Index Curves for Loblolly Pine Plantations on Cutover Site-Prepared Lands

1985 ◽  
Vol 9 (3) ◽  
pp. 166-169 ◽  
Author(s):  
Ralph L. Amateis ◽  
Harold E. Burkhart
Keyword(s):  
Differential Equation ◽  
Pinus Taeda ◽  
Loblolly Pine ◽  
Analysis Data ◽  
Site Index ◽  
Height Growth ◽  
Pine Plantations ◽  
The South ◽  
Stem Analysis ◽  
Natural Range

Abstract Stem analysis data collected from dominant and codominant loblolly pine (Pinus taeda) trees in cutover, site-prepared plantations were used to develop site index curves. The data were collected over much of the natural range of loblolly pine. A separable differential equation which expresses height growth as a function of both height and age was used to develop the site index curves. These site index curves should be applicable to loblolly pine plantations on cutover, site-prepared lands through much of the South.1

Color Aerial Photography for Assessing the Need for Fertilizers in Loblolly Pine Plantations

1988 ◽  
Vol 12 (4) ◽  
pp. 270-273 ◽  
Author(s):  
Charles R. Blinn ◽  
Al Lyons ◽  
Edward R. Buckner
Keyword(s):  
Pinus Taeda ◽  
Loblolly Pine ◽  
Aerial Photography ◽  
Basal Area ◽  
Site Index ◽  
Pine Plantations ◽  
Color Coding ◽  
Foliar N ◽  
Significant Relationships ◽  
Pinus Taeda L

Abstract Color aerial photography was used to assess crown color classes in loblolly pine (Pinus taeda L.) plantations. Three distinct Munsell color classes were delineated on the resulting photographs. Foliar N levels and, to a lesser degree, foliar K levels were directly related to color. Significant relationships between color and site index and color and basal area were shown. Application of color aerial photography, combined with Munsell color coding, could expedite land classification and also make possible more efficient use of fertilizers. South J. Appl. For. 12(4):270-273.

Stand-Level Cubic-Foot Volume Ratio Equations for Planted Loblolly Pine on Site-Prepared Land in the Mid-South Gulf Coastal Plain

1988 ◽  
Vol 12 (1) ◽  
pp. 7-11
Author(s):  
Thomas G. Matney ◽  
Alfred D. Sullivan ◽  
Julia R. Ledbetter ◽  
Robert M. Farrar
Keyword(s):  
Loblolly Pine ◽  
Coastal Plain ◽  
Volume Ratio ◽  
Pine Plantations ◽  
Gulf Coastal Plain ◽  
Predictor Equations

Abstract Volume ratio predictor equations are presented for calculating cubic foot volumes per acre to any top diameter limit in loblolly pine plantations on cutover site-prepared land. An illustrative example of the application of the equations is presented. South. J. Appl. For. 12(1):7-11.

Predicting Mortality After Thinning in Old-field Loblolly Pine Plantations

1983 ◽  
Vol 7 (1) ◽  
pp. 20-23 ◽  
Author(s):  
Ronald C. Lemin ◽  
Harold E. Burkhart
Keyword(s):  
Pinus Taeda ◽  
Loblolly Pine ◽  
Coastal Plain ◽  
Pine Plantations ◽  
Old Field ◽  
Survival Curves ◽  
Pinus Taeda L

Abstract Four equations were compared for predicting mortality after thinning in old-field loblolly pine (Pinus taeda L.) plantations. The model selected is of the form: N2 = [N1a1 + a2(A2a3 - A1a3)] 1/a1 where N1 and N2 denote trees per acre at ages A1 and A2. Survival curves for thinned, old-field loblolly pine plantations in Coastal Plain and Piedmont Virginia are given.

Loblolly Pine Plantation Development is Influenced by Site Preparation and Soils in the West Gulf Coastal Plain

1989 ◽  
Vol 13 (1) ◽  
pp. 17-21 ◽  
Author(s):  
James D. Haywood ◽  
James D. Burton
Keyword(s):  
Loblolly Pine ◽  
Coastal Plain ◽  
Basal Area ◽  
Site Preparation ◽  
Additional Treatment ◽  
Phosphorus Fertilization ◽  
Gulf Coastal Plain ◽  
The West ◽  
Burn Treatment ◽  
Growing Seasons

Abstract Productivity of upland loblolly pine (Pinus taeda L.) plantations was studied under seven site preparation treatments and five soil classes, with and without fertilizer, in the West Gulf Coastal Plain. Generally, the chop-burn-harrow and shear-windrow-harrow treatments resulted in themost basal area (ave. 112 ft²/ac), but the chop-burn-harrow treatment produced the most fiber (2,109 ft³/ac) after 12 growing seasons. Harrowing as an additional treatment after chopping-and-burning increased productivity by 394 ft³/ac over the chop-burn treatment. The leastproductive treatments were underplant-inject and shear-windrow. Generally, basal area per acre was comparatively high on the silty, slowly permeable clay, and very slowly permeable clay soils (ave. 105 ft ²/ac). Two of the soils, silty and slowly permeable clay, had comparatively highvolume production (ave. 1,878 ft³/ac). The least productive sites had gravelly subsoils. Generally, phosphorus fertilization did not influence pine productivity. South. J. Appl. For. 13(1):17-21.

Fusiform Rust Prediction Models for Site-Prepared Slash and Loblolly Pine Plantations in the Southeast

1986 ◽  
Vol 10 (3) ◽  
pp. 145-151 ◽  
Author(s):  
B. E. Borders ◽  
R. L. Bailey
Keyword(s):  
Loblolly Pine ◽  
Regression Models ◽  
Prediction Models ◽  
Geographic Location ◽  
Stand Density ◽  
Site Index ◽  
Cultural Factors ◽  
Pine Plantations ◽  
Permanent Plots ◽  
Fusiform Rust

Abstract Several workers have reported relationships between the incidence of fusiform rust in pine plantations and climatic, edaphic, biotic, and cultural factors. These relationships were investigated quantitatively with a regionwide databank compiled from several replicated unthinned stand density studies. Data from over 2,000 remeasured permanent plots were used to develop regression models that predict the proportion of trees per acre with one or more fusiform rust stem galls. Predictor variables are geographic location, age of the plantation, and site index. Use of the models is illustrated with an example. South. J. Appl. For. 10:145-51, Aug. 1986.

Yield Relationships in Unthinned Loblolly Pine Plantations on Cutover, Site-Prepared Lands

1985 ◽  
Vol 9 (2) ◽  
pp. 84-91 ◽  
Author(s):  
Harold E. Burkhart ◽  
Deborah C. Cloeren ◽  
Ralph L. Amateis
Keyword(s):  
Loblolly Pine ◽  
Coastal Plain ◽  
Measurement Data ◽  
Site Index ◽  
Site Preparation ◽  
Analysis Of Covariance ◽  
Permanent Plots ◽  
Average Height ◽  
Competing Vegetation ◽  
Physiographic Regions

Abstract Data were collected in unthinned loblolly pine (Pinus taeda) plantations on cutover, site-prepared lands across much of the southern United States. Initial measurement data from these permanent plots were used to (1) develop regression relationships between yield of the planted loblolly pine and measurements of the planted pine and competing vegetation, and (2) assess relationships between yield and site preparation methods and physiographic regions (Coastal Plain and Piedmont). These analyses showed that yield of the planted pine component could be predicted adequately from age, average height of dominant and codominant trees, and number of surviving planted trees per unit area. Measurements on the competing vegetation did not significantly reduce the error sum of squares after accounting for the planted-pine variables. An analysis of covariance showed that mean yields (after adjusting for the effects of plantation age, site index, and number of surviving trees) were not significantly different for site preparation classes or physiographic regions. Further analyses showed that survival relationships were similar for the physiographic regions and site preparation classes included. Although the height-age relationships for anamorphic site index curve construction were significantly different for the Coastal Plain and Piedmont, there were no significant differences between site preparation classes within the regions.1

scholarly journals Physalis macrophysa (Solanaceae: Physalinae: subgenus Rydbergis), its taxonomic disposition and relation to other material with large inflated fruiting calyces

2019 ◽  
Vol 13 (1) ◽  
pp. 51-61
Author(s):  
Milo Pyne ◽  
Steve L. Orzell ◽  
Edwin L. Bridges
Keyword(s):  
United States ◽  
Coastal Plain ◽  
Taxonomic Status ◽  
The United States ◽  
Glandular Hair ◽  
Gulf Coastal Plain ◽  
The West

Examination of the lectotype and isotype material of Physalis macrophysa Rydb. show its compatibility with P. longifolia, having nearly glabrous, ovate-lanceolate to broadly lanceolate leaves, and the presence of short, simple antrorse hairs on the petioles and pedicels. Other than its large inflated fruiting calyces (3.0–4.0 cm × 2.5–3.0 cm), it has little in common morphologically with another large inflated calyced Physalis macrosperma which is endemic to deep sands from a portion of the West Gulf Coastal Plain of the United States. Instead, P. longifolia has stems and pedicles that are either nearly glabrous or with antrorse, appressed, non-glandular hair and ovate-lanceolate leaves versus short glandular and non-glandular, spreading, upright hair and cordate to truncate leaves in the aforementioned Physalis macrosperma. We agree with previous authors that P. macrophysa Rydb., if meriting taxonomic status, should be treated as P. longifolia var. subglabrata (Mack. & Bush) Cronquist forma macrophysa (Rydb.) Steyermark or, alternatively, it may simply represent variation within P. longifolia not deserving of any taxonomic status.

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