An assessment of stem breakage and the reduction in timber volume and value recovery resulting from a catastrophic storm: an Irish case study

Abstract

This article reports on a study initiated to assess in detail the volume and value recovery losses associated with damage resulting from a 1998 catastrophic storm in Ireland. The results are based on a 0.39 ha representative site in Swanlinbar forest, County Cavan. Detailed analysis showed that the loss in recovery in the broken stems amounted to a volume loss of 27 per cent with an associated value loss of 29 per cent. On a stand basis this corresponded to 13.4 per cent of stems broken, resulting in a 2.6 per cent volume loss. The value loss of IR£0.87 per cubic metre recovered amounted to IR£310.94/ha or 2.8 per cent of the potential revenue. During the milling of the blown timber, no additional loss was incurred as a result of log defects resulting from storm damage. A significant relationship between diameter at breast height (d.b.h.) and the occurrence of breakage was established, with the smaller diameter trees more likely to snap than those with larger d.b.h. measurements. No significant relationship between the location of the breakage along the stem and the d.b.h. of the trees was found.