As our climate changes, stem cracking in conifers will become an increasing concern for the forestry industry. Forest Research is undertaking a major study and asks forestry professionals across to report stem cracks using TreeAlert, the online tree health reporting tool.
Stem cracks, also known as drought cracks, are a type of defect found in standing conifer trees. Affected timber is unsuitable for structural uses. This defect is very common in Norway spruce and firs but can also occur in Sitka spruce.
The cracks are caused by internal tensions in the stem. A crack formed this was then spreads, spiralling up the tree and outward radially, until eventually it hits the cambium and a scar in the bark is formed. It is these scars which enable trees with stem cracks to be identified.
Contact: Forest Research Senior Scientist, Rubén Manso.