As a result of the imbalances in the forestry market and the increased demand for wood products worldwide, the resource of branches resulting from the exploitation of a forest has attracted special attention from researchers, in order to use these secondary resources judiciously and obtain an added value superior to classic uses. In this context, the current research took into consideration the use of spruce branches to obtain panels with a transverse structure. The work methodology has focused on the process of obtaining panels with a transverse texture and on determining the physical–mechanical properties of the created panels. The results regarding the panel density (determined as a ratio between mass and volume of specimens) showed about 693 kg/m3, static bending resistance parallel to the face of 5.5 N/mm2, resistance of adhesion of 5.6 N/mm2, shear strength parallel to face of 4.1 N/mm2, and screw pull-out resistance perpendicular to the face of 31.3 N/mm2, highlighting that the properties were in accordance with the European standards and that the panels obtained were suitable for obtaining furniture products with a special aesthetic aspect. As a general conclusion of the research, it can be stated that spruce branches are a sustainable wood resource with great possibilities to add more value in the form of panels with a traverse texture.

The increasing demand on the wood market makes it necessary to use all secondary resources, including the wood branches and spindles. The properties of deciduous branches and softwood spindles were evaluated in order to create wood panels, highlighting the transverse texture with high value added. The research analyzed the properties of the wood from deciduous (beech, maple) branches and from conifer (spruce, fir) spindles. The methodology of obtaining panels with transversal structure was also presented. The production of minor wood (branches or spindles) was 254 m3/ha/year in the case of beech (branches) and 109 m3/ha/year in the case of spruce (spindles). The proportion of compression wood for spruce had an average value of 40.6%. A similar value of tension wood for beech was obtained. The modulus of elasticity for pine spindle wood was 71.7% lower than the modulus of elasticity for bending strength in the trunk. The quality index was 36.7% lower in the case of spindles than in the case of pine trunk, and the value of the quality ratio in branch maple wood was 2.61% lower than in trunk wood. Thus, even if it is not the only efficient solution, wood in the minor portions can be used to make high value-added panels such as those that highlight the transverse structure.

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The evolution of the request in wood production leads to larger stem wood consumption, intensive harvesting and consequently the environmental impact increases. One of the most ignored secondary resources in spite of limited reserves, branch wood could be used in new added value products as an alternative to stem wood, providing its characteristics are known and understood. This paper is part of a larger research project, which here compares the compression strength parallel to the grain of branch wood of maple (Acer spp), beech (Fagus sylvatica L.) and Scots pine (Pinus sylvestris L.) with compression strength of stem wood. Results were interpreted on micrographs viewed on SEM and Laboval compound microscope. Excepting Scots pine, who's strength was only a half, maple and beech branch wood had similar strengths to stem wood of the same species, which makes them alternative raw materials.

This research aimed to evaluate the calorific characteristics of two biomasses from larch and oak sawdust in the form of native or torrefied pellets. Some calorific features of these two kinds of biomasses, such as ash content, higher and lower calorific values, calorific density and many others were highlighted, allowing for a comparison between oak and larch torrefied/not torrefied pellets. Installations and methods used for the process of torrefaction and for highlighting some of the calorific features were also evaluated. As a result of experiments, it was demonstrated that the larch and oak pellets were different in terms of density, but that after thermal treatment, the calorific values of both increased considerably. The investigations evidenced some increases in calorific value, up to 15.8%, for both the larch and oak sawdust/pellets. One of the main conclusions of this research was that, even though the role of biomass has diminished considerably in the last few decades, its role as a sustainable fuel remains relevant. Its use will become more widespread when the world’s population understands that fossil fuels are depletable and that they must be replaced by renewable fuels such as biomass.