Ultrathin Wood Laminae–Thermoplastic Starch Biodegradable Composites

Novel fully biodegradable thermoplastic composite laminates reinforced with ultrathin wood laminae were prepared through a hot-pressing process by using two different thermoplastic starch(TPS)matrices.The microstructure and physical properties of the resulting unidirectional and bidirectional laminates were studied.The investigated materials presented a complex microstructure,in which the porosity of the wood laminae was almost entirely occluded by the polymer matrix.The mechanical behavior of the laminates was strongly affected by the obtained microstructure,and matrix penetration in wood pores led to biodegradable composites with elastic modulus and tensile strength higher than those of their constituents.Finally,thermal welding and thermoformability tests proved how these materials possess features typical of thermoplastic materials.

Performance of a small-scale chipper for professional rural contractors

The study determined the productivity, fuel consumption and product quality obtained with a new tractor OWered drum chipper, designed to reduce the gap between industrial chippers and small-scale chippers. The machine as tested with poplar logs and beech slabs, considered as representative of the raw material commonly used for ergy wood production. After accounting for accessory work and delays, productivity of green chips ranged between and 6 tons per scheduled machine hour, which was very good for a tractor-powered unit. Specific fuel consumption f oven-dry chips varied between 2.5 and 3.0 L per ton, or 0.6 L per m_3. These figures compared favourably with those btained from previous studies of both smaller and bigger chippers. Chip quality was very good. Samples contained no versize particles, qualifying for use in small-scale plants. The average size of beech chips was significantly larger than r poplar chips, possibly due to the higher strength of beech wood.

Exploring the silvicultural and economic viability of gap cutting in Mediterranean softwood plantations

Gap cutting consists of the removal of all trees growing on a small surface, varying in size from 200 to 600 m2. In Italy, gap cutting has been successfully tested for introducing the natural regeneration of native species into softwood plantations, thus ac- celerating the transition towards climax hardwood stands. Depending on plantation types and conditions, gap cutting should be start- ed at an age between 70 and 80 years and the system should include at least 12 to 15 gaps, in order to produce enough wood to cover costs. Generally, natural regeneration is firmly established within 5-7 years from treatment. Gap cutting also offers superior results to selection thinning, the latter producing about 35% less value and incurring 25% to 30% more costs. As for all regeneration cuts, the success of gap cutting depends on wildlife control in order to prevent extensive damage to the regeneration.

A Wood Preservative Based on Commercial Silica Nanodispersions and Boric Acid against Fungal Decay through Laboratory and Field Tests

The paper is based on the development of a wood preservative without metal salts to be used in use classes 3 and 4 (EN 335), eco-friendly and harmless to humans and animals. Boric acid was used as a biocide, due to its effectiveness against fungi and insects. It is also known to be easily leached from wood exposed to weather action. Colloidal silica was therefore added in the formulations to guarantee the fixation of boric acid to wood. The different formulations were tested for the protective efficacy against decay fungi through laboratory tests (EN 113) and field trials (EN 252). The results were promising, especially those concerning boron fixation and efficacy against decay fungi through laboratory tests, where some formulations and retentions gave a durability class 1 (very durable) according to EN 350-1. The fourth evaluation, after 50 months of field trials showed only a slight difference between the treated samples and controls.

Evaluation of Durability Conferred by an Oleothermic Treatment on Chestnut and <i>Douglas fir</i>through Laboratory and in Field Tests

The research evaluated two wood species, chestnut and Douglas fir, that are widespread in Tuscany, treated with an oleothermicprocess. Efficacy of this treatment against fungal decay was assessed through laboratory and field tests. The aim of this research was to investigate if an oleothermic process could add value to these natural resources when utilized in Use Class 4 (EN 335) for agricultural purposes such as vineyard poles. The treatment was effective on sapwood of both wood species in laboratory test, giving a protection similar to the untreated heartwood but in case of chestnut, it was easily washed away. In field test the leaching during the outdoor exposure reduced the resistance to fungal decay in both species.