Characterization of ring shake defect in chestnut (Castanea sativa Mill.) wood in the Lazio Region (Italy)

摘要

The incidence of ring shake in chestnut wood (Castanea sativa Mill.) from eight sites (237 total trees) in the Lazio territory, in central Italy, was investigated. All the areas studied are coppice managed. The aim of this study was to increase knowledge of this defect through the measurement and classification of numerous indices. Using analysis of variance and correlation analysis, age was found to be the principal factor affecting the ring shake defect, the incidence of which was highest in trees aged 30 years or over. The highest risk of splitting occurred in the 12- to 14-year-old age group, although cracking started with a certain intensity at an age of 7–8 years. Comparing trees of the same age (25–30), it can be seen that diameter was not strongly related to magnitude of defect, but it had the effect of moving the ring shake location outwards. Wood defects (star shake, injuries, double core and eccentricity of core) and stem defects (cortical cancer, epicormic branches, dead branches and bark cracking) were not significantly correlated with shake: indeed, only bark cracking and injuries seem to have a slight influence on ring shake risk.