Damage severity of wood-destroying insects according to the Bevan damage classification system in log depots of Northwest Turkey.

The aim of the study was to determine damage severity of wood-destroying insects on logs stored in forest depots. The Bevan damage classification (BDC) system, developed in 1987, was utilized to determine damage severity in log depots in 21 locations throughout seven provinces in Turkey. Pheromone traps were placed in those locations at the beginning of April in 2015 and 2016. Furthermore some stored wood within the log depots were checked and split into small pieces to collect insects that damage wood. The BDC system was used for the first time to measure the severity of insect damage in log depots. Twenty-eight families, 104 genera and 123 species were identified in this study. Based on the BDC system, the highest damage was found from the Cerambycidae and Buprestidae families. Arhopalus rusticus was determined as the insect responsible for the highest amount of damage with 8.8% severity rating in the pheromone-trapped insects group. When the stored wood material was considered, Hylotrupes bajulus was found to be the cause of the highest damage. The lowest damage values were among the predator insects (Cleridae, Trogossitidae, Cantharidae) and those feeding on fungi colonized on the wood (Mordellidae, Cerylonidae, Nitidulidae). Some other predator insects of the Tenebrionidae family (Uloma cypraea, Uloma culinaris, Menephilus cylindricus) and Elateridae family (Lacon punctatus, Ampedus sp.) exhibited relatively higher damage severity values since they had built tunnels and made holes in the stored wood material. When the environmental factors were considered, the Buprestidae family exhibited a very strong positive relationship (p < 0.005) with insect frequency distribution (r = 0.922), number of species (r = 0.879) and insect density (r = 0.942). Both families showed the highest number and frequency during July and August, highlighting the importance of insect control and management during these months.

Incorporation of hazelnut shell and husk in MDF production.

Hazelnut shell and husk (Coryllus arellana L.) is an abundant agricultural residue in Turkey and investigating the possibilities of utilizing husk and shell in panel production might help to overcome the raw material shortage that the panel industry is facing. The aim of this work was to investigate the possibilities of utilizing hazelnut shell and husk in medium density fiberboard (MDF) production. To produce general purpose fiberboards, fiber-husk and fiber-shell mixtures at various percentages were examined in this study. The results indicated that panels could be produced utilizing hazelnut husk up to 20% addition without falling below the properties required in the standards. Shell addition was restricted up to 10%, because higher addition levels diminished the elastic modulus and internal bond strength below the acceptable level.

The manufacture of particleboards using mixture of peanut hull (Arachis hypoqaea L.) and European Black pine (Pinus nigra Arnold) wood chips.

This research was conducted to investigate the suitability of peanut hull to produce general purpose particleboards. A series of panels were produced using peanut hull and mixture of peanut hull and European Black pine wood chips. Particleboards were manufactured using various hull ratios in the mixture (0%, 25%, 50%, 75% and 100%). Urea formaldehyde adhesive was utilized in board production and boards were produced to target panel's density of 0.7 g/cm3. Panels were tested for some physical (water absorption and thickness swelling), chemical (holocellulose content, lignin content, alcohol-benzene solubility, 1% NaOH solubility, hot water solubility and cold water solubility) and mechanical (modulus of rupture, modulus of elasticity and internal bond) properties. The main observation was that increase in peanut hull in the mixture resulted in a decrease in mechanical and physical properties of produced panels and panel including 25% hull in the mixture solely met the standard required by TS-EN 312 standard. Conclusively, a valuable renewable natural resource, peanut hull could be utilized in panel production while it has been mixed to the wood chips.