Near infrared spectra obtained from leaf surfaces of Eucalyptus grandis seedlings were calibrated against physiological measurements of plant water stress, namely: relative water content, leaf water potential and stomatal conductance. In a controlled environment facility, spectral data were obtained from both abaxial and adaxial leaf surfaces as well as upper and lower leaves in the stem. The strongest coefficients of determination using cross-validation were r²_CV = 0.85 for relative water content, r²_CV = 0.74 for leaf water potential and r²_CV = 0.80 for stomatal conductance. The use of a portable NIR instrument enabled the rapid assessment of physiological status of seedlings and would enable in situ, non-destructive, high-throughput monitoring of drought and recovery in the field. This would be particularly useful for non-destructive measurement in longitudinal studies.

Eucalyptus pellita has traditionally been grown in South-East Asia as a fibre source, particularly for pulp production. It has also been identified as a potential species to complement native hardwoods for solid wood and veneer production. However very little information is available in the literature on the mechanical and processing properties of E. pellita, particularly for plantation-grown trees in the tropics. Individual trees from two sites (7-year-old and 9-year-old) in the Malaysian state of Sarawak were selected for recovery trials of solid wood and veneer. The major impediment to utilisation of both solid wood and veneer is the high incidence of end-splitting, particularly for solid wood where the mean green board to air-dry board recovery was only 31%. In addition, the presence of knots in the veneer was undesirable but neither site was maintained for veneer production or had been pruned. The mechanical properties (strength, stiffness, hardness and density) were all sufficient to suggest E. pellita, when properly managed is ideal for solid wood production (flooring, furniture) and appearance-grade veneer.

Eucalyptus is a diverse genus from which several species are often deployed for commercial industrial tree plantation due to their desirable wood properties for utilization in both solid wood and fiber products, as well as their growth and productivity in many environments. In this study, a method for monitoring the health status of a 22.78 ha Eucalyptus pellita plantation stand was developed using the red-green-blue channels captured using an unmanned aerial vehicle. The ortho-image was generated, and visual atmospheric resistance index (VARI) indices were developed. Herein, four classification levels of pest and disease were generated using the VARI-green algorithm. The range of normalized VARI-green indices was between −2.0 and 2.0. The results identified seven dead trees (VARI-green index −2 to 0), five trees that were severely infected (VARI-green index 0 to 0.05), 967 trees that were mildly infected (VARI-green index 0.06 to 0.16), and 10,090 trees that were considered healthy (VARI-green index 0.17 to 2.00). The VARI-green indices were verified by manual ground-truthing and by comparison with normalized difference vegetation index which showed a mean correlation of 0.73. This study has shown practical application of aerial survey of a large-scale operational area of industrial tree plantation via low-cost UAV and RGB camera, to analyze VARI-green images in the detection of pest and disease.

The establishment of commercial tree plantations in Malaysian Borneo began with a progression of various species, including Pinus caribea, Acacia mangium, Gmelina arborea, Falcataria moluccana (formerly Albizia falcataria) and Eucalyptus deglupta. Ultimately, A. mangium, intended for the production of pulplogs, dominated the plantation landscape. However, recent widespread devastation of A. mangium by the Ceratocystis pathogen in Sabah has led to a shift in plantation species, which has also necessitated a review of downstream end products. This paper analyses growth data and estimates productivity for species in a taxa trial as well as a F. moluccana progeny trial in a single trial area in Sabah. A eucalyptus hybrid (Eucalyptus urophylla x Eucalyptus grandis (UG)), Eucalyptus pellita, F. moluccana, Acacia crassicarpa and A. mangium exhibited high productivity after three years, with an average mean annual increment of approximately 35 m³ ha⁻¹ y⁻¹ or better. Mean annual increment curves show that productivity declined slightly for the eucalypts and F. moluccana after three years. Acacia species experienced a sharper decline associated with disease-caused mortality, with A. mangium the most seriously affected. The mean basic density of the UG hybrid and F. moluccana was 560 kg m⁻³ and 252 kg m⁻³ at six and five years of age, respectively, and E. pellita had a mean basic density of 629 kg m⁻³ at six years of age. The importance of growth and wood properties in the selection of species suitable for planted forest development in the wet tropics is discussed.

A comparison of moisture loss fromPinus radiatasapwood by conventional forced air-drying and a novel supercritical carbon dioxide (scCO₂) dewatering process has been examinedin situusing magnetic resonance microimaging. Air-drying results in the nonuniform removal of moisture within the wood volume, leading to a dry core and wet perimeter where water evaporated, whereas the scCO₂dewatering process resulted in moisture expulsion more uniformly throughout the volume of the specimen, especially so within the earlywood.