Main content area

Ring shake occurrence related to growth parameters and prediction model for its presence before felling

Birbilis, Dimitris, Kakavas, Konstantinos, Chavenetidou, Marina
European journal of wood and wood products 2018 v.76 no.4 pp. 1353-1358
Castanea, adults, burl wood, coppicing, earlywood, felling, forests, juvenile wood, latewood, microscopy, orchards, pith, regression analysis, statistical models, trees, wood, xylem vessels
This work includes observations on chestnut logs at woodcutting areas, measurements of some growth characteristics and observations under microscope of chestnut wood cross sections with ring shakes. Some types of ring shakes were developed in logs with abnormalities, such as forking, double-pith, burls, pith eccentricity and elongated cross sections. The ring shake defect mainly occurred on logs from older trees with large diameters coming from orchards. On logs coming from coppice forests, where young chestnut trees were cut without reaching large diameter, ring shake rarely (and only on logs from trees cut after two rotations) occurred. Ring shakes rarely occur on juvenile wood. They usually occur on adult wood from logs of tree’s base. The presence of a wider ring followed by narrower rings or the width differentiation along the same ring of a cross section, consist of an area that ring shake is possible to be developed. Relations between age, log diameter and ring width heterogeneity with ring shake were determined. A prognostic statistical model based on logistic regression was developed giving success of up to 80% using age and diameter as estimators. Finally, microscopic observations revealed breakages of vessel members and fibers detachment either in the earlywood or in the latewood, in the area between two annual rings.