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Hevea brasiliensis (rubber tree), a major source of natural rubber, could also be an important source of lumber as senescence occurs. However, latex collection is known to affect Hevea brasiliensis (rubber tree) wood formation and consequently, wood properties. The impact tapping (cutting made in the bark of the tree for latex harvest) has on the tree and the way the tree responds after tapping is often overlooked. Knowledge on wood properties of tapped rubber trees in Nigeria would enhance its sustainable utilization which is especially important in developing countries where lumber is limited. Variation in specific gravity and shrinkage of rubberwood wood due to tapping duration was examined. Tapping duration had significant effect in specific gravity and longitudinal shrinkage of rubberwood but had no effect on tangential and radial shrinkage. The specific gravity (SG) of rubberwood ranged from 0,55 - 0,59. Longitudinal shrinkage (average 1,42 %) was higher than typically observed for mature wood. Average tangential shrinkage for rubberwood of all the ages was 5,37 % while radial shrinkage ranged from 2,87 % to 3,84 %. decrease in SG observed in trees tapped for 20 years may indicate the initiation of senescence. Tapped rubberwood could be used in areas not exposed to high moisture as well as in other wood composites. [ABSTRACT FROM AUTHOR]

Rubberwood (Hevea brasiliensis Muell. Arg) is underutilized in most developing countries but has potential to be a solution to the shortage of wood for pulp, paper and wood composite products at the end of its production cycle. Determining and understanding its fibre properties (fibre dimensions and morphology) is key in its utilization for pulp and paper as well as composites. This study assessed the effect of age on the fibre properties of rubberwood. Samples of wood at four ages (10, 15, 20 and 25 years) were obtained at both the axial (base and top of merchantable length) and radial direction (innerwood, middlewood and outerwood). Slivers were obtained from the samples and macerated to provide individual fibres for optical measurement. Fibre dimensions at the four ages were measured, and their morphology was determined. Fibre properties and morphology were significantly affected by age at p = 0.05. Average fibre length was 1.47 ± 0.12 mm, with non-constant variation observed across the different ages, and from pith to bark. Average lumen width was 16.87 µm, and fibre diameter ranged from 25.02 µm to 27.23 µm. The fibre properties of rubberwood potentially make it suitable for pulp and paper production as well as wood composite boards. [ABSTRACT FROM AUTHOR]

The physical properties of thermal treated wild-grown Bambusa vulgaris were investigated, the test samples were treated with five different treatment regimes; 100, 110,120, 130 and 140°C and with treatment duration 10, 20 and 30 minutes respectively, and sampling heights of Base, middle and top. The colour of the treated samples was observed to change; it changed with increase in temperature and duration, the colour turned to brown at the temperature 120°C/30minutes and turned darker brown at temperature 140°C, the Specific Gravity (SG) and Equilibrium Moisture Content (EMC) of thermal treated Bambusa vulgaris were also examined. The result of analysis of Variance on the S.G as a result of the treatment effect, the sampling height temperature variation (°C) and treatment time (minutes) had significant effect on the specific gravity at 5% level of probability. The highest mean value of S.G (0.61) was found at the base sampling height while the least mean value (0.46). The results of the EMC of thermal-treated bamboo clearly revealed the ability of bamboo to absorb and loss water to atmosphere. The treated bamboo at temperature and time variations; 140°C/30minutes had a lowest (6.06%) EMC value while the control samples and samples at 100°C had the relative highest (10.84%) values. Thermal treatment, changes the bamboo colour, decreases the Specific gravity and Equilibrium moisture content improved dimensional stability and durability of Bambusa vulgaris. [ABSTRACT FROM AUTHOR]

The need for environmental sustainability calls for a radical change from the use of synthetic wood preservatives which persist in the environment even after wood has been taken out of service. There has therefore been a growing interest in the development of efficacious biocides from plants, prompting the exploration of castor seed oil as a potential wood antifungal in this study due to its reported antimicrobial properties. Thus, this study aimed at evaluating the resistance of castor oil treated P. caribaea wood against two strains of wood basidiomycetes. Five trees of Pinus caribaea were harvested at Shasha Forest Reserve, Osun State. Wood samples were obtained from the top, middle and base of the trees. The samples were conditioned and treated with four formulated fungicides prepared from mechanically extracted oil of castor seeds. The treated and control samples were inoculated with Sclerotium rolfsii (Brown rot) and Ganoderma lucidum (White rot) for 24 weeks. Parameters such as oil yield, preservative absorption, weight loss and compressive strength of the treated wood samples were determined. ANOVA was used in analyzing the data generated. Results show that the oil yield of the seed of the plant is 41.75%. The preservative absorption of the wood ranged between 114.85 - 277.12 (Kgm-3), weight loss (1.36 - 15.85%) and MCS// (33.05 - 48.35N/mm²). Sampling height and preservative concentration significantly influenced weight loss of the wood (p<0.05). The 30% preservative concentration performed best, having the least weight loss (1.71% and 1.61%) and highest MCS// (47.06N/mm² and 44.65N/mm²) after exposure to S. rolfsii and G. lucidum, respectively. The brown rot (4.12%) was more virulent than the white rot (3.66%) on the basis of wood weight loss, however, the MCS// results indicated otherwise. It is concluded that castor seed oil is effective in protecting wood against white and brown rot fungi. [ABSTRACT FROM AUTHOR]

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Bamboo culm is a hygroscopic lignocellulosic material. Hygroscopic properties may be disadvantageous in bamboo material if applied in certain applications and modes where and when extreme moisture variations are likely to occur. This study was aimed at evaluating the moisture absorption and resistance including dimensional stability properties of neem seed oil-treated split bamboo samples using two methods of treatment. Split bamboo samples from the same source were oven-dried at 103±2°C, conditioned to 11.76% mean moisture content, and treated by completely soaking them in oil at room temperature for 24 hours and by soaking in hot oil at 60°C for 4 hours, with untreated samples as control. Results showed that samples soaked in hot oil at 60°C for 4 hours had both the least percentage water absorption and higher anti-swell efficiency, followed by samples soaked in oil at room temperature for 24 hours. Shrinkage in the longitudinal, radial, and tangential directions also followed the same trend. Conclusions and recommendations were made in line with the outcome of the study. [ABSTRACT FROM AUTHOR]