The objective of this work was to evaluate the influence of different useful areas provided by the planting spacings (3 × 1, 3 × 2, 3 × 3, 3 × 4 m) on the production and permeability of heartwood and sapwood of Eucalyptus grandis and Eucalyptus grandis × Eucalyptus urophylla clones at 4 years old. Regardless of the clone, there was no effect of planting spacing on the heartwood/sapwood relation and wood permeability. All clones showed a heartwood decrease with increased height, regardless of planting spacing, and E. grandis (B) was the only one that had its heartwood percentage positively and significantly correlated with the dendrometric variables (DBH and commercial height). The use of the dymethil yellow compound was indispensable in defining the heartwood and sapwood regions in the samples from 50% of the stem height. The heartwood permeability was low in all evaluated clones, suggesting vessel obstruction by tyloses or other deposits, while sapwood permeability reached 405.4 cm3/cm.atm.s.

ResumoO objetivo deste trabalho foi avaliar a deformação residual longitudinal, o índice de rachaduras (de topo de toras e tábuas), o deslocamento da medula e os defeitos de secagem nas tábuas das espécies de Khaya ivorensis e Khaya senegalensis para a produção de madeira serrada. O material foi proveniente de um plantio experimental em Linhares, ES, Brasil, sendo utilizadas cinco árvores por espécie, com 19 anos de idade. Com as árvores em pé foi realizada a leitura da deformação residual longitudinal, utilizando o méto-do CIRAD -Forêt. Após o corte das árvores, os topos inferiores das toras da base foram fotografados para a mensuração das rachaduras e do deslocamento da medula. As rachaduras de topo e os empenamentos das tábuas também foram mensurados, após a secagem. No geral, não houve diferenças significativas nas médias de deformação residual longitudinal, índice de rachaduras de toras e tábuas e deslocamento da medula entre as espécies. Todavia, a espécie Khaya ivorensis apresentou as maiores dimensões de rachaduras de topo de toras e de tábuas, enquanto, as tábuas de Khaya senegalensis apresentaram os maiores empenamentos. Os índices das variáveis avaliadas não são elevados ao ponto de inviabilizar o uso e a qualidade das duas espécies de mogno africano para a produção de madeira serrada, sendo importante ponderar, principalmente, a forma e dimensões das árvores e os defeitos da madeira serrada em regiões mais próximas da medula e em idades mais jovens. Palavras-chave:Khaya, Deformação residual longitudinal, Rachaduras, Defeitos da madeira serrada. AbstractThe aim of this work was to evaluate the longitudinal residual strain, the index of splits (end of logs and boards), the displacement of the pith and the drying defects on the boards of the species of Khaya ivorensis and Khaya senegalensis for lumber production. The material comes from an experimental plantation in Linhares, ES, Brazil, with five trees per species being utilized, at age 19 years. The reading of the longitudinal residual strain using the method CIRAD -Forêt on standing trees was taken. After cutting of the trees, the end of logs was photographed for measurement of splits and displacement of the pith. The end splits and warping of the boards were also measured, after drying. Overall, there were not statistical differences in longitudinal residual strain, index split of logs and boards and displacement of the pith between species. However, Khaya ivorensis showed the larger dimensions of end split logs and boards, while, the boards of Khaya senegalensis had higher warping. The indexes of the variables are not high to the point of rendering unfeasible the use and the wood quality of the two species of African mahogany for the lumber production. It is important to consider, however, the shape and dimensions of trees and lumber defects in regions closest of the pith and at younger ages.Keywords: Khaya, Longitudinal residual strain, Splits, Lumber defects. INTRODUÇÃOOs plantios de mogno africano têm aumentado no Brasil nos últimos anos, com o...

RESUMOO objetivo deste trabalho foi avaliar o desempenho de uma serraria de pequeno porte, localizada na região sul do Espírito Santo, processadora de madeira de eucalipto. O desempenho da serraria foi avaliado pela eficiência e pela amostragem do trabalho, por um período de quatro dias, cada um destes correspondente a nove horas de trabalho. A eficiência média foi de 5,06 m 3 /operário/dia, ao passo que o trabalho produtivo médio foi de 77,1%, superior ao valor mínimo de 75% sugerido pela literatura. A serraria apresentou um bom desempenho, conforme os parâmetros avaliados e a discussão de dados presentes na literatura específica, resguardadas as características intrínsecas da mesma, tais como porte, nível de automação, maquinário e matéria-prima.Palavras-chave: serraria de pequeno porte, Eucalyptus spp., estudo do trabalho produtivo. ABSTRACTThe aim of this work was to evaluate the performance of a small eucalypt sawmill from the southern region of the State of Espirito Santo. The performance was evaluated based on efficiency and work delay ratio techniques for four days (nine hours a day). The average efficiency was 5.06 m 3 /operator/day, while the average productive work was of 77.1%, greater than the minimum suggested in the literature (75%). According to the characteristics evaluated and the literature data, the sawmill presented good performance considering its inherent particularities, such as automation level, machinery and raw material.

Growth in world demand for wood implies a search for new fast growing species with silvicultural potential, and in this scenario for native species such as Paricá . Thus, the objective of this study was determining the physical and mechanical wood properties of the Schizolobium amazonicum species (known as Paricá in Brazil). Trees were collected from commercial plantations located in the north of Brazil with ages of 5, 7, 9 and 11 years. Four logs from trees of each age in the longitudinal direction of the trees were obtained, and later a diametrical plank of each log was taken to manufacture the specimens which were used to evaluate some physical and mechanical properties of the wood. The basic density of Paricá was reduced in the basetop direction and no difference between the radial positions was observed, while the average basic density of this wood was characterized as low. The region close to the bark showed less longitudinal contraction and also greater homogeneity of this property along the trunk, while for tangential contraction the smallest variation was found in the region near the pith. Paricá wood contraction was characterized as low. Age influenced most of the mechanical properties, where logs from the base had the highest values of mechanical strength.

The variable environmental conditions of the Amazon forest can affect the wood properties of the tree species distributed across its diverse phytophysiognomies. Carapa guianensis (Andiroba) occurs in upland and floodplain forests, and the wood and oil of its seeds have multiple uses. The aim of this study was to evaluate the wood properties of C. guianensis trees in upland and estuarine floodplain forests of the Amazon River. Eight trees were selected, with four being from the upland and four from the floodplain forests. The fiber length, fiber wall thickness, vessel diameter and frequency, microfibril angle, specific gravity and wood shrinkage were evaluated. The juvenile and mature wood zones were determined according to these variables. The fiber length, fiber wall thickness and specific gravity increased, and microfibril angle decreased, in the pith to bark direction. Only the fiber length variable was efficient for delimiting juvenile, transition and mature wood. The fiber length, wall thickness and specific gravity of wood were higher in upland forest trees. However, the environment did not alter the beginning of the formation and proportion of C. guianensis mature wood. This information is important for the log fit in cutting diagrams, aiming toward improving the production, classification and processing of pieces with specific quality indexes in order to direct them to appropriate wood uses.

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There are reports relating color to extractives, however there is a lack of information about the effect of other characteristics on the colorimetry of wood. Thus, this study aimed to evaluate the longitudinal and radial variability of color and its relationship with the basic density and extractive contents of Calycophyllum spruceanum wood from a six-year-old plantation located in Rio Branco, Acre, Brazil. The determination and assessment of the wood color were carried out by the Commission Internationale de L’Éclairage - CIE-L*a*b* system. The basic density and extractive contents were determined according to current technical standards. The species wood color was classified as yellowish olive. The highest and lowest lightness (L*) were longitudinally observed in the base (cutting height) and diameter at breast height (DBH), taken at 1.30 m from the ground. In relation to radial position, the lightness (L*) was lower in peripheral regions of the trunk. Higher concentrations of redness (a*) and yellowness (b*) and saturation (C) occurred along the DBH and the external radial position. In evaluating age, the extractive contents were not correlated to the wood color, while the basic density was correlated with a*, b*, C and h* colorimetric parameters. The colorimetric characterization of this specie contributes to its proper identification and a more homogeneous classification of lumber, and can be used from the log break-down (sawing) to its end use, adding commercial value to the wood.

Variabilidade física e anatômica da madeira Avaliou-se a influência do espaçamento de plantio na variação radial da densidade aparente da madeira, através da densitometria de raios X, e das dimensões das fibras a partir de amostras do cerne periférico das baguetas da direção norte. Os dados foram submetidos à análise de variância, pelo teste F e as médias comparadas pelo teste de Tukey, quando a hipótese da anuidade era rejeitada. Houve maior crescimento em diâmetro e incremento médio anual em diâmetro (IMAD) para as árvores plantadas nos maiores espaçamentos (7x6 e 10x10 m). A densidade aparente média e dimensões das fibras da madeira de K. ivorensis não diferiram entre si em função do espaçamento de plantio aos cinco anos de idade. A densidade aparente da madeira teve correlação significativa com o DAP das árvores plantadas, no maior espaçamento (10x10 m), tendendo esta a diminuir conforme aumento do diâmetro a altura do peito (DAP) das árvores. Em todos os espaçamentos houve tendência comum de variação radial da densidade aparente da madeira, sendo menor próximo à medula e conforme o distanciamento da mesma tendeu ao aumento próximo a casca.Palavras-chave: mogno africano, crescimento em diâmetro, densidade da madeira. AbstractThe objective of this study was to evaluate the influence of spacing between trees in radial growth and quality of Khaya ivorensis wood, at 5 years of age. The plantations are located in the city of Pirapora, MG, Brazil. We assessed three planting densities: 5x5, 7x6 and 10x10 meters. We selected 10 trees in each spacing considering the north and south cardinal directions to remove the radial wood samples using nondestructive method, at 40 cm above the ground. We evaluated the influence of planting spacing in the radial variation of the apparent density of the wood through X-ray densitometry, and the size of the fibers from the peripheral heartwood of the north radial samples. Data were subjected to analysis of variance by F test and the means were compared by Tukey's test, when the null hypothesis was rejected. There was a higher diameter growth and mean annual increment (MAI) in diameter for the trees planted in greater spacings (7x6 and 10x10 m). The apparent average density and dimensions of K. ivorensis wood fibers did not differ with planting spacings at five years of age. The bulk density of the wood had significant correlation with DBH of trees planted in the greatest spacing (10x10 m), tending to decrease as the DBH of trees increase. In all spacings, there was a common trend of radial variation of the apparent density of the wood, being lower near the core and increasing as the distance from the same tended to increase, next to the bark.