ZLV Online

Abstrakt

As the use of harvester technology and cut-to-length harvesting systems in the Czech Republic has been increasing lately, the volume of timber, for which it is possible to use several methods of the volume determination for forest management documentation, is also rising. These methods are (i) using harvester production – inventory software outputs on felling site, (ii) using pile measuring method at the roadside, or (iii) a combination of both. Volume differences between methods (i) and (ii), however, cause problems in timber stock documentation, and for accepting harvester data outputs by state-owned company Forests of the Czech Republic (Lesy České republiky) there are accuracy requirements of ± 2% maximal difference from the control pile measurement. In this study, harvester data outputs were compared with the pile measurements on 168 piles from 53 felling sites. Only 11.3% of recorded values proved ± 2% of volume difference. The most of the measurements (38.6%) were in the category of ± 10–25% difference. The biggest difference was recorded on larch (9.2%), followed by broad-leaved trees (-7.48%), pine (-2.38%), and the lowest difference was observed in spruce (2.09%). For more information see Summary at the end of the article.