REDUCING THE RISK OF RING SHAKE IN CHESTNUT

P. Fonti, F. Giudici
This contribution presents results of a 3 year project on chestnut (Castanea sativa Mill.) ring shake (RS). The main objective was the examination of the relationships between radial wood cohesion, growth stresses and RS occurrence. Investigative studies were carried out on wood material collected in chestnut coppice forests from the southern part of the Swiss Alps. Analyses were performed on the basis of a comparison of wood with and without RS. Anatomical investigations of the RS privileged plane of fracture (earlywood area) showed that ring shaken wood displays a higher amount of rays and smaller earlywood vessel lumina. Mechanical rupture testing revealed that earlywood radial split resistance is positively correlated with ring width. Examination of longitudinal strain-induced displacement performed on the stem surface of standing coppice trees did not reveal the existence of a direct relationship between high stress level and RS occurrence. Consequently it has been highlighted that the principal cause of RS in chestnut is associated with the unbalance between the weak structure of the tangential wood plane and the release of growth stresses. Stress overloaded trees react by producing a strengthened wood. However when trees are cut, as a consequence of the relieving of high growth stresses, mechanically originated RS are developed. Nevertheless mechanical testing proved that not all trees are prone to RS in the same way, what offers the forest manager the opportunity to operate in order to reduce the risk of RS.
Fonti, P. and Giudici, F. (2005). REDUCING THE RISK OF RING SHAKE IN CHESTNUT. Acta Hortic. 693, 733-742
DOI: 10.17660/ActaHortic.2005.693.99
https://doi.org/10.17660/ActaHortic.2005.693.99
Castanea sativa Mill., coppice, southern Swiss Alps, wood anatomy, wood technology
English

Acta Horticulturae