Check development on jack pine logs in Eastern Canada

Logs in storage are subject to check damage. The severity of the problem may vary with various environmental and storage conditions. In this study, an investigation was conducted on the development of checks in debarked and bark-on jack pine (Pinus banksiana) logs in Eastern Canada. In the summer of 1999, jack pine trees were felled, and then the logs were debarked and stored in a sawmill yard. The logs were inspected and sampled every 2 to 4 weeks. The moisture content (MC) and the amount and depth of checks present in each log were determined. Bark-on logs stored in sunny and shaded environments served as controls. The results showed that the MC of debarked logs dropped rapidly, whereas the MC of bark-on logs stored in a shaded environment decreased much slower. More checks were found on debarked logs than on bark-on ones. On debarked logs, the average number and depth of checks increased proportionally with the duration of storage. However, formation of the deepest checks did not correlate with storage time. Fewer checks were detected on logs with intact bark, especially on those stored in the shade.