Surveys in Private and Communal Forests: Data Collection Methods in Bavaria

More than half of the forest land in Bavaria belongs to private forest owners, who contribute a large amount of the industrial timber supply. The level of information about private forests is in comparison to the communal forests inadequate. The increasing demand for data about the forest sector in Bavaria can be partially covered by regular inventories but requires supplementary monitoring activities. Regular surveys based on voluntary participation deliver data, but often do not fulfil statistical requirements due to low response rates of 15–20% to postal surveys. The Bavarian annual postal cutting survey has been built up over 5 years using a roster of voluntary participants. This pragmatic and cost-effective approach provides reliable data for statistical purposes and gives insight in the forest management activities of small-scale forest owners. Recent technical developments, in particular the availability of grids and digital land-use maps, facilitate the random sampling of forest owners. This approach has been applied in a climate change project, but the results did not meet the expectations because of low response rates. The rather labour- and cost-intensive census of forest owners as applied in the project in Eastern Bavaria cannot be recommended except in exceptional circumstances. In the described project a qualitative approach with four distinct questionnaires has been adopted in order to identify ways to reach forest owners that are either not interested in their forests or do not respond to requests. Due to low response rates the objectives of the study could only be partially achieved.