Speaker
Description
The current development of harvesters and harvesting systems makes it possible to calculate timber volume with a high accuracy, albeit over bark. Despite this, countries where timber is traded based on under-bark measurements, such as Poland, continue to measure volume manually or using photo-optical methods. Meanwhile in Finland, where over-bark measurement is in use, the volume calculated by harvester software can be used in trading. In the end, it is mainly bark or its absence that causes variability in timber volume calculation.
During processing, a certain amount of bark is reduced by the harvester knives, which, as a consequence, artificially lowers the measured diameter and calculated volume. Very careful calibration and accurate measurement of diameter and length does not guarantee that the log volume obtained represents the real volume. This is due to many factors, including season, e.g. in the spring, bark is easily removed or shaved with the harvester head knives, and the system is not able to recognise if the diameter was measured with bark or without bark.
The objective of this research was to find out how much bark is removed during log processing of pine to construct new model of bark thickness that needs to be subtracted when calculating log volume. Initial measurements are being caried out in Winter 2026, where bark thickness has been measured along logs after delimbing, with particular attention to thickness of bark partially removed (under knives) and thickness of natural bark (not shaved). Detailed methods, early data analysis and first results will be presented at the conference in the form of new subtraction of bark thickness for pine, to get close to real timber volume from harvester software.
| Keywords | CTL; Bark reduction |
|---|
