WITHIN-TREE VARIABILITY OF WOOD COLOR IN PAPER BIRCH IN QUEBEC

Color variations in paper birch wood were examined in boards sawn from sawlogs from 168 trees harvested from two different stands. Approximately 2250 boards were sawn from the logs. The within-tree variability was considered by looking at the effect of log quality and log height class on board color. Results show that neither the log quality nor the log height class had a significant effect on the proportion of discolored wood on the surface of the board. However, these log parameters had an effect on the wood colorimetric variables. Log position in the tree was found to significantly influence sapwood yellowness as well as discolored wood luminosity and redness. Log quality on the other hand significantly influenced only one colorimetric factor, sapwood redness.