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Based on an enquiry, risk perception among non-industrial private forest owners is described in relation to climate change and forestry hazards. Of the respondents, 11% took action to remedy the effects of climate change. Out of a given set, hazards were ranked according to each respondent's experience of recent substantial financial loss to the estate and in relation to his or her willingness to make investments aimed at risk reduction. For each hazard, the respondent assessed the risk in four classes ranging from very high to negligible risk. Six hazards were considered most problematic in all three aspects: browsing damage, falling timber prices, damage by wind, spruce bark beetle, root rot and pine weevil. A majority of the respondents claimed to take action to reduce the risk associated with at least one hazard, while 35% did not know whether they did. Excluding climate change, the need for decision support was the largest in relation to damage by wind owing to a combination of perceived high risk an...

Regulations defining the maximum opening size in the sub‐alpine region of Sweden, introduce new planning issues. The combinatorial problems that arise in harvest planning become very complex, but can be solved by different methods. In a case study, three different ways to find a solution were examined: a random search algorithm, a simulated annealing algorithm and the prebiased random search method found in the SNAP II program. Two different alternatives were studied, one with no road in the area and one with a road constructed. All three methods were found to give feasible solutions. The simulated annealing produced the best solutions, in terms of present net value, while the SNAP II program was the fastest. The SNAP II did not give as good solutions as the others in the case with a road, probably due to the lack of a distinct gradient in the structure.

A method for forecasting the log‐class distribution resulting from harvesting forest stands is investigated. The diameter distribution of a stand is approximated by a two‐parameter Weibull density function, the parameters of which are recovered from stand level characteristics. Theoretical bucking is performed for actual and simulated distributions and the resulting log yields are compared. An application to 40 stands indicates that an accurate prognosis can be expected, given a good approximation of the diameter distribution. For cases with multimodal diameter distributions or many small trees, the prognosis is unreliable.