Accurancy of working day structure determining of the timber skidding by snapshot observations

One of the most difficult technological operations in forest utilization is wood transport, especially its first stage i.e. extraction. This is related to the fact that the forest operations must be economically effective, but also safe for the forest environment. Difficult terrain conditions require determining and choosing the optimal variant of skidding. The most popular method for optimizing work is the use of working day photography. However, it is time−consuming and labor−intensive, that is why it is possible to use an alternative way of measuring working time, i.e. snapshot observations. It is therefore important to determine which measurement method is appropriate for the complicated and variable production processes in forestry. The aim of the research was to assess the accuracy of snapshots at intervals of 1 and 5 minute in relation to the stopwatch time study (which was a reference measurement), carried out for a two−stage wood logging in quasi−mountain terrain conditions of the Elbląg Upland (N Poland). It’s mountain like characteristics causes some difficulties in the forest works. Data for the study were collected in two periods – summer and winter. We did not prove statistically significant differences between the methods studied