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A B S T R A C TThis paper examines the current wood tracking information systems used in international wood trade aiming to prevent and control illegally logged timber and wood products trade. Moreover, innovative log tracking mechanisms and technologies are also described and assessed. Wood tracking can add value to the wood product, by establishing an information system aiming to recognize and locate legal wood and wood products. Apart from the traditional punching and painting log-tracing methods, there are various digital wood traceability information systems for recognition, log tracking and monitoring, including barcodes, QR codes, RFID, microchips etc. Furthermore, various innovative wood tracking systems are also presented and discussed. The aim of the paper is to describe and quote those methods used in wood trade sector, to identify current trends and perspectives and to quote them as to their reliability, practicality, level of information provided and cost. Further it provides insight from log-traceability methods used in Greek Forests.

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A kenaf (Hibiscus cannabinus L.) plantation grown in N.Greece during the period June±October 1996 provided the raw material for experimental particleboards. After harvesting, the kenaf stems were storaged under shelter for a week, the core of each stem was separated from bark and both were dried at about 20% and 10% moisture content, respectively, and chipped by a hammermill. Kenaf core, bast ®bers and industrial wood chips were mixed in various proportions in order to produce three-layer E2 grade UF bonded particleboards. Kenaf core chips were characterized by a lower slenderness ratio than wood chips of the middle layer. Bulk density of both core chips and ®bers was lower than that of wood chips. Substitution of wood chips with kenaf core chips in the middle layer up to 75% slightly affects static bending and internal bond of the boards, but reduces screw holding strength and increases water absorption and thickness swelling; a 100% substitution deteriorates all properties except static bending. In boards with surface layers from kenaf bast ®bers or from ®bers:wood chips (50:50), static bending and surface roughness are improved, while the other properties tested are deteriorated. Substitution of kenaf core chips in the middle layer with ®bers in proportion 50% negatively affects the board properties except static bending. It can be concluded that core chips and bast ®bers from kenaf stems may substitute industrial wood chips in the middle and surface layers of the boards, respectively, up to 50%. Versuchsspanplatten aus griechischen Kenaf PlantagenDer Rohstoff fu Èr die Versuchsspanplatten wuchs von Juni bis Oktober 1996 auf einer Kenaf-Plantage (Hibiscus cannabinus L.) in N. Griechenland. Nach der Ernte wurden die Kenafstengel fu Èr eine Woche unter Dach gelagert, dann wurde das Holzgewebe im Stengelinneren von der Rindenschicht getrennt, anschliessend auf ca. 20% bzw. 10% Feuchtigkeit getrocknet und beides in einer Hammermu Èhle zerkleinert. Die Herstellung dreischichtiger harnstoffharzverleimter (E 2 Typ) Spanplatten erfolgte unter Verwendung verschiedener Beimischungen aus Kenafholzspa Ènen, Kenaffasern und Industrieholzspa Ènen. Kenafholzspa Ène und Kenaffasern zeichnen sich durch eine niedrigere Streudichte als Industrieholzspa Ène aus; daru È-berhinaus weisen Kenafholzspa Ène einen niedrigeren Schlankheitsgrad auf im Vergleich zu den Mittelschichtspa Ènen der Industrie. Der Ersatz von Industrieholzspa Ènen durch Kenafholzspa Ène in der Plattenmittelschicht bis zu einem Anteil von 75% beeinusst unwesentlich die Biege-, und Querzugfestigkeit der Platten, hat aber eine negative Auswirkung auf das Schraubenhaltevermo Ègen, die Dickenquellung und die Wasseraufnahme; ein Zusatz von 100% Kenafholzspa Ènen zur Mittelschicht bewirkt eine Verschlechterung aller Spanplatteneigenschaften mit Ausnahme der Biegefestigkeit. Spanplatten, deren Deckschichten aus reinen Kenaffasern oder aus einer Beimischung von Kenaffasern und Industrieholzspa Ènen in einem Verha Èltnis von 50:50 bestehen, weisen ho Èhere Qualita Èt bez...

Black locust (Robinia pseudoacacia L.) is regarded as an important natural resource almost throughout the world but relatively little is known about the within-tree variability of the anatomical characteristics of its wood. Discs 2 cm thick were cut at 2.25 m intervals, from the ground level to the top from ten black locust trees, 18–37-years-old, from the University Forest of Taxiarchi, Chalkidiki, Greece. The discs were used for the determination of growth rate and cell dimensions (fiber length and vessel member length and diameter) and their withintree variability (radial, oblique, vertical). Growth rate increased within the first 5–9 growth rings from the pith and then gradually decreased. Oblique variation of growth rate did not exhibit any clear tendency but a decrease at the top. In the case of vertical variation, growth rate decreased gradually with the year of cambium formation. Radial variability curves were found to be typical for the dimensions of cells (fibers, vessel members) especially for the fiber length. A rapid increase in cell dimensions was observed in the first 7–11 growth rings, the juvenile zone. Oblique and vertical variation of cell dimensions did not exhibit any clear tendencies.