Pinus Caribaea Var Research Articles

A new approach for predicting board MOE from increment cores

Key message Increment cores can provide improved predictive capabilities of the modulus of elasticity (MOE) of sawn boards. Multiple increment cores collected at different heights in a tree provide marginally increased accuracy over a single breast-height core, with higher labour costs. Approximately 50% of the variability of the static bending MOE of individual boards is explained by the predicted MOE obtained from a single increment core taken at breast height. Context Prediction of individual board MOE can lead to accurate optimisation of the value extracted from forest resources, and enhanced decision-making on the management and allocation of the resource to different processors, and improve the processors ability to optimise grade allocation. Aims The objective of this study is to predict the MOE of individual sawn boards from the MOE measured from cores collected from standing trees. Methods A five-parameter logistic (5PL) function and radial basis function interpolants are used to obtain a continuous distribution of MOE throughout a log. By developing a “virtual sawing” methodology, we predict the individual board MOE for sixty-eight trees consisting of locally developed F1 and F2 hybrid pines (Pinus caribaea var. hondurensis × Pinuselliottii var. elliottii). Results Moderate correlations for individual board predictions are observed, with R2 values ranging from 0.47 to 0.53. Good correlations between average predicted board MOE and average measured MOE are also observed, with R2 ≈ 0.83. A pseudo-three-dimensional approach, accounting for variation in height in the tree, affords marginally greater accuracy and predictive capability at the cost of increased data collection and processing. By using a single breast-height core, we can obtain a similar level of prediction of individual board MOE. Conclusion We have presented a novel non-destructive evaluation approach to predict the MOE of individual boards sawn from trees. This approach can be adapted to other wood properties, and other wood products obtained from trees.

PHYSICAL PROPERTIES OF WOOD Pinus caribaea var. caribaea, Pinus caribaea var. hondurensis AND Pinus oocarpa FOR PENCIL PRODUCTION

The behavior of the physical properties of wood is important for its use in the industrial sector. Manufacturing for pencil production requires raw material with low specific mass and high dimensional stability. The objective of this study was to evaluate the properties of the physical specific basic mass properties, anhydrous and green, as well as the retractability of the 14 years old Pinus caribaea var. caribaea, 25 years old Pinus caribaea var. hondurensis and 35 years old Pinus oocarpa in the medulla sense of the bark, base and top of the trees. All species come from the Brazilian Cerrado region afforestation. As for dimensional stability, the Pinus caribaea var. caribaea and Pinus oocarpa had similar behaviors to the volumetric contraction, when evaluating the coefficient of anisotropy of wood species of Pinus caribaea var. caribaea had higher values of anisotropy coefficient, however, all tropical pine studied, qualify as a raw material for the pencil industry, being an alternative species traditionally used.

Accounting for competition in multi-environment tree genetic evaluations: a case study with hybrid pines

Key message A novel multi-environment competition individual-tree mixed model resulted in better fit, and greater individual narrow- and broad-sense heritabilities than the model without competition, notably for traits showing competition. In multi-environment tests, the proposed model would allow tree breeders to select genotypes with the best performance in both additive direct and competition breeding values, increasing forest productivity. ContextGenetic merit of trees is known to be affected and interact with local competition effects as well as changes across environmental conditions. Recent studies showed that competition genetic effects can affect the genetic variance and bias the tree breeding values, and its covariance with direct breeding values has been variable across traits.AimsThe present paper extends a mixed-model methodology to the problem of accounting for competition in a multi-environment set of forest genetic trials and exploring its impact on genetic variances as well as the multi-environment genetic correlation.MethodsThe proposed model is illustrated using data from two full-sib trials of Pinus elliottii var. elliottii × Pinus caribaea var. hondurensis F1. Dispersion parameters and (co)variance of total breeding values were estimated for diameter at breast height, total tree height, and stem straightness at age 10.ResultsFor traits showing competition effects (diameter at breast height and total tree height), the proposed multi-environment competition model gave better fit than the simpler model. Accounting for competition increased the direct additive variance, reduced the residual variances, and did not change significantly the across-site additive genetic correlation. However, for diameter at breast height, top 5% best genetic rankings showed differences.ConclusionWhen traits are strongly affected by inter-tree competition, the use of the proposed model in multi-environment analyses can efficiently identify the phenomenon with general benefits in the fitting of genetic components and open the door to select on the basis of competitiveness.

Influence of wood’s anatomical and resin traits on the radial permeability of the hybrid pine (Pinus elliottii × Pinus caribaea) wood in Australia

Wood permeability has a major effect on industrial wood processing and utilization. Wood anatomy and resin influence the permeability of wood. Understanding and manipulating these influences is important to optimize the manufacture and use of forest products. This study investigated the relationships between wood anatomical traits, radial permeability, and resin content of samples collected from 19-year-old hybrid pines (Pinus elliottii var. elliottii × Pinus caribaea var. hondurensis) from Queensland, Australia. The earlywood tracheid tangential lumen diameter and axial resin canal diameter were statistically positively correlated with radial permeability. The heartwood proportion and the frequency of axial resin canals were statistically negatively correlated with radial permeability and positively correlated with resin content. The axial resin canal diameter, sapwood proportion, latewood content, ray frequency, and earlywood tracheid lumen diameter increased from pith to bark, whereas the axial resin canal frequency decreased. Resin was found distributed throughout the wood microstructure, from pith to bark in many samples, and in both heartwood and sapwood. However, there was a much greater quantity of resin in heartwood and wood from the middle (inner radius) of the tree, with widespread occurrence of resin impregnation in the axial tracheids.

Enfoque multivariado en experimentos de extracción de madera en plantaciones forestales

El presente trabajo fue realizado con el objetivo de evaluar, técnica y económicamente la extracción de El presente trabajo se realizó con el objetivo de evaluar, técnica y económicamente la extracción de madera en plantaciones de Pinus caribaea var. caribaea de la empresa forestal Macurije, ubicada en la provincia de Pinar del Río, Cuba. Para ello, se llevaron a cabo estudios de tiempos y movimientos teniendo como criterios de evaluación "productividad" y "costo unitario" de extracción de la madera. La evaluación del desempeño de los tractores articulados (skidders) y de las yuntas de bueyes en diferentes sistemas de aprovechamiento y clases de pendiente se realizó por medio de experimentos factoriales (3 × 3 × 2) univariados y multivariados (costo unitario e/o productividad), siguiendo un diseño al azar en bloques (B1 = 21 años y B2 = 32 años), con los factores "maquinaria" y "pendiente" con tres niveles y "sistema de aprovechamiento" con dos niveles. Se evidenciaron la viabilidad y la utilidad del enfoque multivariado en la evaluación de la extracción de madera; es más viable extraer la madera con el sistema de tronco entero en plantaciones de 32 años. La interacción maquinaria-pendiente tuvo influencia significativa en la variación del conjunto costo-productividad. El skidder John Deere 548E, por presentar menor costo unitario y mayor productividad que el J-80A, es el recomendado para la extracción semimecanizada de la madera. El más viable es la yunta de bueyes por su mayor rentabilidad. Sin embargo, por su baja productividad, solo podrá ser utilizado en combinación con otras máquinas o en periodos de producción desacelerada. Su uso exclusivo no es práctico ya que implicaría aumentar significativamente su cantidad para compensar su baja productividad.

Multiple soil element and pH interactions constrain plant performance on tropical soils with a long history of fire

Agriculture and forestry in savanna soils worldwide are often constrained by multiple soil limitations. We measured the effect of fertilisation on growth of Pinus caribaea var. hondurensis in order to improve savanna soil productivity in the Northern Territory, Australia. Growth responses to nitrogen, potassium, sulfur and a combined trace element treatment (abbreviated to N × K × S × T) with basal phosphorus (P) application on three soils, and N × P × K × S × T on another three soils, were examined in glasshouse factorial experiments. Without P, there was little response to N, S or T. Growth was usually greatest on N + P + S treatments. The P applications increased soil pH and growth, while N and S applications decreased pH. Growth was consistently poor at soil pH < ~5.2; a pH where exchangeable cations can be leached from the soil and aluminium can become more mobile. Responses to P, N, S and K, and likely also to zinc, were consistent with savanna soils with a long history of nutrient losses due to fire and weathering. Establishing productive plantations or agriculture will require detailed knowledge of soil properties, careful attention to soil pH and balanced fertiliser applications so as not to produce perverse outcomes. Long-term protection from fires could improve soil conditions, to be balanced against the risks of crop loss through unplanned fire.

Reforestation in Venezuela – current situation and future perspectives

The location of the Bolivarian Republic of Venezuela in the tropical region of northern South America, in the Northern Hemisphere, with a total area of 91.64 million ha, of which 49.6 million correspond to natural forests (54.12 % of the national territory). Venezuela shows a series of geographic advantages that allow a rapid growth and development of the trees in comparison with the temperate zones where the growth is extremely slow. However, the occurrence of deforestation processes has intensified in a sustained way in the recent history of the country.
 In the period from 1920 to 2008, the loss of 26.43% of the forested area has been recorded. Likewise, in the period 1975-1988, deforestation was estimated at 216,000 ha year-1, equivalent to 2.9 million ha in 13 years (Catalan 1992). Deforestation has now increased to worrying levels and according to FAO estimates (2010), in Venezuela, a forested area of more than 288.000 ha year-1 is deforested.
 In the middle of the 20th century several public and private institutions began an important effort to reforest areas of sandy soils of scarce depth on a bed of highly impermeable clay. With erosion processes generated as a result of strong winds that causes severe damage to the little existing vegetation. It was expected that with the passage of time this region could become a desert in the oriental plains of Venezuela. This is how the Maderas del Orinoco Companies (CVG - PROFORCA), the Venezuelan Corporation of Guayana (CVG), Smurfit Kappa Cartón of Venezuela, San Carlos Forestry Development, Masisa. Propulso, among others, started in different regions of the country the establishment of plantations for various purposes. For this they have used fast growing forest species such as: Pinus caribaea var hondurensis, Eucalyptus Urophylla, Acacia magnium, Caraipa llanorum, Tectonia grandis, Hebea brasiliens, Gmelina arborea, Erisma uncinatum, among others. At present, a reforested area of 650.000 ha has been reached. This has favored the protection of natural habitats by reducing the pressure for exploitation and use of the forests.
 The legal framework established in the new National Constitution, approved in 1998, is based on decrees of 1825-1829 of the Liberator Simón Bolívar and classifies the territory in diverse forest areas establishing a modern environmental conservation policy. A historical summary and the current legislation with the classification that promises a rational management of the national territory is presented.

Optimisation of cross-banded laminated veneer lumbers manufactured from blending hardwood and softwood veneers

This paper presents a methodology to optimise the manufacturing strategy of structural cross-banded laminated veneer lumbers (LVL-C) manufactured by mixing species. The methodology is illustrated by blending native-forest spotted gum (Corymbia citriodora) with plantation southern pine (Caribbean pine (Pinus caribaea var. hondurensis) and slash pine (Pinus elliottii var. elliottii)) veneers. The aim is to minimise the cost of a family of products (i.e. several types of product manufactured from the same veneered stock) using a maximum allowable number of hardwood veneers, and in which each product has different targeted stiffness and embedment strength. Genetic algorithm, which is widely used in the optimisation of structural products, was selected as the optimisation algorithm. The orientation of the veneers and veneer grades are considered as design variables. Results show that the developed algorithm was able to consistently converge to similar solutions for all investigated cases, demonstrating its robustness. For all cases, the “high” modulus of elasticity graded spotted gum and southern pine veneers were found to be predominant in the final products. LVL-C are found in cases with high targeted embedment strength. Finally, the obtained optimum construction strategies are validated against experimental results.

Bioenergia com resíduos do desdobro da madeira de Pinus caribaea var. hondurensis

Forest species of the genus Pinus are the most used in the wood processing industries in Brazil, with the significant generation of residues during the process of wood. The objective of this study was to evaluate the energetic characteristics of the residue of Pinus caribaea var. hondurensis at 40 years and its application in the form of briquette. The proximate analyses, heating value, bulk and energetic density of the wood residue was carried out to subsequent production of briquettes and evaluation of its energetic and physico-mechanical characteristics. The briquetes of wood residues of P. caribaea var. hondurensis exhibit physico-mechanical and energetic characteristics that prove to be a viable source for energetic use, with energy density of19,072 MJ.m-3.

Modelos matemáticos para la determinación del turno óptimo en plantaciones forestales

En el presente trabajo se proponen procedimientos de determinación de los turnos técnicos, económicos y técnico-económicos en plantaciones forestales. Se procedió a la determinación de los criterios clásicos de máxima productividad: incremento medio anual y máximo valor esperado de la tierra. Para la determinación de los turnos, además de utilizar las herramientas analíticas (por ajuste de modelos de crecimiento forestal) y gráficas convencionalmente utilizadas, se propusieron modelos de programación matemática: el modelo R-01 basado en la programación lineal entera, para la determinación de los turnos monocriterios, y los modelos R-02 y R-03 basados en la programación por metas ponderada entera y en la programación por metas lexicográficas entera, respectivamente, para la determinación del turno con múltiples objetivos. La validez de los modelos propuestos fue verificada a través de la consistencia y realismo biológico de las edades de rotación técnicas, económicas y técnico-económicas determinadas por índice de sitio en plantaciones de Pinus caribaea Morelet var. caribaea Barr. & Golf. de la empresa Macurije. Los turnos técnicamente óptimos variaron entre 31 años y 35 años según la calidad del sitio y los turnos económicamente óptimos entre 18 años y 21 años. Se percibió que los turnos técnico-económicos son altamente influenciados por el criterio de mayor importancia, tanto en el enfoque de metas ponderadas como en el de metas lexicográficas. Los resultados encontrados para el Pinus caribaea var. caribaea con esos enfoques indicaron turnos intermedios entre los técnicos y los económicos, variando estos entre 23 años y 25 años.

Radial permeability of the hybrid pine (Pinus elliottii × Pinus caribaea) in Australia

The radial permeability (gas and liquid) of the hybrid pine (Pinus elliottii var. elliottii [PEE] × Pinus caribaea var. hondurensis [PCH]) was investigated for wood samples collected from 30 trees that were 19 years of age and represented various genotypes and stocking rates. The PEE × PCH hybrid is now a very important resource for the Australian forestry industry, producing logs used to manufacture a diverse array of wood products. The permeability of wood influences many important wood properties and industrial processes. For all data combined from all radial sampling positions, there was no significant effect of genotype and stocking rate on radial permeability. Both gas and liquid permeability increased from pith to bark positions within the tree. Conversely, resin content decreased from pith to bark positions. Gas and liquid permeability were significantly positively correlated, and a highly significant negative relationship was also found between permeability (gas and liquid) and resin content.

Produtividade de <i>Pinus caribaea</i> VAR. <i>hondurensis</i> e suas relações com atributos químicos dos solos em região de Cerrado brasileiro

A silvicultura com espécies exóticas desempenha importante papel socioeconômico no Brasil, fornecendo matéria-prima para a produção de madeira, lenha, carvão e celulose, dentre outros. Nesse sentido, torna-se necessária o aprofundamento do conhecimento sobre as variáveis ambientais que controlam a produtividade do Pinus, em especial, as edáficas. O objetivo do presente trabalho foi avaliar a variabilidade espacial dos atributos químicos de solo e planta em um plantio comercial de Pinus caribaea var. hondurensis. O experimento foi instalado no campus da Faculdade de Engenharia de Ilha Solteira (Unesp), localizado em Selvíria, Estado de Mato Grosso do Sul, Brasil, em um LATOSSOLO VERMELHO Distroférrico, textura muito argilosa. Foram analisados os seguintes atributos químicos do solo: fósforo (P), matéria orgânica (MO), potencial hidrogeniônico (pH), potássio (K), cálcio (Ca), magnésio (Mg), acidez potencial (H+Al), alumínio (Al), soma de bases (SB), capacidade de troca catiônica (CTC), saturação por bases (V%) e, cálcio (CaT), magnésio (MgT) e alumínio (m) na CTC. Pode-se estimar os atributos químicos da camada de 0,10-0,20 m através dos atributos da camada superficial (93%), não sendo, portanto, necessária à coleta dos atributos subsuperficias, representando oportunidades de economia em analises e de coleta de solos para futuros trabalhos. Todos os atributos de solo e planta apresentaram dependência espacial simples na área do estudo, exceto, altura, diâmetro a altura do peito e acidez potencial na camada de 0,10-0,20 m, evidenciando que o manejo de Pinus pode ser realizado de acordo com site especifico nas condições do estudo. O potássio foi o atributo de solo que apresentou cokrigagem com a produtividade de Pinus, bem como os melhores indicadores para a estimativa da produtividade.

ARTIFICIAL NEURAL NETWORKS FOR MODELING HYPSOMETRIC RELATIONSHIPS OF Pinus caribaea Morelet var. caribaea Barr. & Golf.

The present study was carried out to compare the performances of regression models and Artificial Neural Networks (ANNs) in hypsometric relationships modeling and to analyze the influence of ANN type and sample size on ANN performance. The database was consisted by 65 circular plots of 500 m² in which Diameter at Breast Height - DBH (cm) and Total Height - Ht (m) of 2538 trees were measured in plantations of Pinus caribaea var. caribaea in Macurije forest company, Cuba. The study was carried out in three stages: i) Fit of traditional hypsometric models and sigmoidal growth models; ii) ANNs training and comparison of the selected ANN with the regression model selected; iii) Analysis of sample size and ANN type influences on the estimates precision by means of a completely random experimental design with 5x2 factorial arrangement, with the factors sample size (N) and ANN type (R). The results indicated that the best equation to estimate trees heights was that of Gompertz. The ANNs MLP 1-4-1 and MLP 8-4-1 were superior to the selected equation (Gompertz). Multi-Layer Perceptron ANNs generated more accurate estimates and their performances were less influenced by the sample size.

PRODUCTIVIDAD DE UN HARVESTER EN RALEOS DE PLANTACIONES DE PINOS EN EL NORESTE ARGENTINO

Se analizó la productividad de segundos y terceros raleos en plantaciones de Pinus taeda y Pinus elliottii var. elliottii x Pinus caribaea var. hondurensis realizados con harvesters de ruedas en el Noreste Argentino. Los árboles cosechados en los segundos raleos presentaron un volumen medio de 0,43 m³ para Pinus taeda de 12 años y 0,36 m³ para pino hibrido de 10 años, mientras que en los terceros raleos este valor fue de 0,71 m³ para Pinus taeda de 13 años y 0,75 m³ para pino hibrido de 15 años respectivamente. Se desarrollaron modelos de tiempos parciales para cada una de las actividades que componen el ciclo operacional y se determinó la influencia del tipo de raleo, especie cosechada, número de productos elaborados, volumen de los árboles y forma de volteo, sobre el tiempo insumido por cada actividad. Los modelos ajustados fueron integrados en un modelo de productividad efectiva consiguiéndose un coeficiente de determinación ajustado R2 Aj de 0,61. El volumen de los árboles resultó significativo para explicar la duración de todas las actividades evaluadas, siendo especialmente determinante en el volteo de los árboles, su desrame y trozado. El tipo de raleo afectó al tiempo de ubicación, mientras que la especie afectó al tiempo de desrame y trozado. La elaboración de hasta tres productos diferentes requirió un mayor tiempo destinado al desrame y trozado. Ocurrió un aumento de la cantidad de productos cuando se realizaron terceros raleos sobre pino hibrido, respecto Pinus taeda.

Elaboración de Briquetas a Partir de Residuos de Aserrín Aglutinados con Almidón de Maíz y su Posible Aplicación como Aislante Térmico

Se desarrolló una metodología para el aprovechamiento sostenible de los residuos de aserrín de Pinus caribaea var. honduresis proponiendo aplicaciones diferentes a bioenergía. Se elaboraron dos formulaciones de briquetas aglutinadas con almidón de maíz: 25/75 almidón/aserrín (lote A) y 36/64 almidón/aserrín (lote B). Los mejores resultados se obtuvieron con las briquetas del lote A: 45,2 ± 0,4 mm diámetro y 101 ± 3 mm longitud; friabilidad < 1 %; humedad 9,4 ± 0,5 %; densidad 0,45 ± 0,01 g/ml; resistencia al aplastamiento 4,5 x 104 ± 0,7 x 104 kg/m2; poder calorífico 20.799 kJ/kg. Se estimó la capacidad de aislamiento térmico a 41,6 ± 0,4 °C y 57,3 ± 0,1 °C; en el primer caso, la superficie de las briquetas se mantuvo en 29,0 ± 0,4 °C y en el segundo, en 34,7 ± 0,8 °C. Los resultados indican que el material obtenido es apto para ser utilizado en revestimiento de interiores, aislante térmico, elemento decorativo o de expresión artística. La implementación de procesos productivos a partir de esta metodología contribuiría a la disminución del deterioro ambiental y mitigación del cambio climático, debido a que retarda la devolución a la atmósfera del CO2 fijado en los procesos de producción forestal.

Climate change impacts on the aptitude area of forest species

Climate change has been most evident since the mid-twentieth century and has caused unprecedented planetary change. Economically, the agricultural sector may be the most affected by climate change, as agricultural and forest species are highly dependent on weather conditions. Given the background, the aim of this study was to assess the potential impact of climate changes on the delimitation of areas suitable for cultivation of the forest species Azadirachta indica (neem), Bactris gasipaes (pupunha), Pinus caribaea var. hondurensis, Pinus elliottii var. elliottii, Pinus oocarpa, Pinus taeda, Tectona grandis (teak) and Toona ciliata (cedar) in the Espírito Santo state, Brazil. For characterization of current climate, we used data from 1982 to 2011. The Global Circulation Model (MCG) and MRI-CGCM2.3.2 were used, respectively, to estimate mean annual precipitation and average air temperature for 2050. The projections generated point to reduction in monthly rainfall and increase in average air temperature by 2.1 °C. The annual water deficit will thus tend to increase in most regions within the state. Current and future agro-climatic zoning were compared using a paired comparison matrix. In future, all eight forest species will experience a reduction in suitable cultivation area, with teak likely to suffer least impact and cedar and pupunha likely to experience most widespread changes. Cedar, neem, pupunha, Pinus caribaea and teak will experience the highest percentages of exchange between classes, indicating the emergence of new areas suitable for cultivation under projected future climate conditions. The methodology can be adjusted to agricultural and forestry crops of other countries.

Physical Quality of an Oxisol in Different Agricultural Systems in Brazilian Cerrado

The soil physical quality is a way of evaluating the current condition of forest plantations that is growing in the southeast region of Mato Grosso do Sul State. In this sense, this work aimed to evaluate the impact of the forest plantations on the physical quality of an Oxisol (Haplic Acrustox) in Cerrado. The experiment was conducted in the Experimental area of the Teaching and Research Farm, of the Engineering college of Ilha Solteira (UNESP), located in the city of Selvíria-MS, situated in the conditions of the Brazilian Cerrado. The soil samples were collected at depths of 0.00-0.10; 0.10-0.20; 0.20-0.30 and 0.30-0.40 m in three areas cultivated for 30 years: area (1) Pine forest (Pinus caribaea var. hondurensis); (2) Eucalyptus forest (Eucalyptus camaldulensis); (3) Reforested ciliary forest, being used a completely randomized design, with 25 replications and 3 treatments. The analyzed attributes of the soil was: macroporosity (Ma), microporosity (Mi), total porosity (TP), bulk density (BD), real particle (RP), soil resistance to penetration (PR), gravimetric moisture (GM), volumetric moisture (VM) and sand, silt and clay contents. The three evaluated areas presented macroporosity below the critical limit (0.100 m³ m-³), thereby impairing the root development. The three evaluated areas affected the physical quality of the soil. Being the physical attributes that most influenced in the reduction of the soil physical quality was the bulk density, total porosity, microporosity, macroporosity and soil resistance to penetration.

Growth ring width of Pinus caribaea var. hondurensis and its relationship with wood proprieties

Growth ring width of Pinus caribaea var. hondurensis and its relationship with wood proprieties

Cytosine Methylation Analysis of Pinus elliottii × Pinus caribaea var. hondurensis and Their Parental Lines

Heterosis is the superiority of hybrids over their parental lines with regard to all kinds of agronomic traits and has been broadly investigated. However, the underlying genetic basis is so far obscure. To figure out the relationship between DNA methylation and heterosis in Pinus, we analyzed the cytosine methylation pattern in Pinus elliottii Englem. × Pinus caribaea var. hondurensis hybrids and their parents using the methylation-sensitive amplified polymorphism (MSAP) method. Our results show that the total DNA methylation levels were not significantly different between hybrids and their parental lines, indicating that heterosis might not be associated with DNA methylation level. Comparison between the elite and poor hybrids shows a different methylation pattern, indicating that readjustment of the DNA methylation pattern might be associated with heterosis. Fragment analysis shows that the RNA methylase (ermBP) gene, which can reactivate gene expression, may play an essential role in hybrid vigor. Our study provides a clue to understand the genetic basis underlying heterosis, which may be important for Pinus breeding in the future.

Comparison of Methods for Estimating Mechanical Properties of Wood by NIR Spectroscopy

Near-infrared (NIR) spectroscopy provides a rapid alternative to traditional methods of wood property assessment. For organizations who assess wood properties on a large scale, multisite, multispecies calibrations are of practical interest. We examined NIR spectroscopy for the estimation of density (at 12% moisture content), modulus of elasticity (MOE), and modulus of rupture (MOR) using clear wood samples obtained from several pine species (Pinus caribaeavar. bahamensis, var.hondurensis, and var. caribaea, P.chiapensis,P.maximinoi,P.oocarpa,P.taeda, andP.tecunumanii). We compared different methodologies for collecting spectra, that is, benchtop instrument versus benchtop fiber-optic probe and field portable fiber-optic probe, and different wood surfaces (radial and transverse). Calibrations based on the benchtop instrument were superior to those obtained using the fiber-optic probe systems. Difficulty with adequately representing the sample when collecting spectra using a fiber-optic probe and lower quality spectra explain the differences among the data sets. Spectra collected from radial and transverse surfaces provided similar calibration statistics. The calibrations obtained for density (R2 = 0.81, SECV = 38.5 kg/m3) and MOE (R2 = 0.81, SECV = 1124 GPa) using benchtop instrument spectra demonstrate that it is possible to obtain general calibrations for estimating the wood properties of a number of tropical, subtropical, and temperate pine species.