The mapping of aspen and birch
|The mapping of aspen and birch in Hälsingland has been done on mission by The Swedish University of Agricultural Science . The data base will be used to correlate capture sites for wood dependent insects (beetles) with presence of aspen and birch of different ages. As an extra result, the sum of aspen and birch (more or less all deciduous trees except for some local populations of alder) has been found and compared to foresting companies’ data. The presence of deciduous trees often follows humid or wet areas and a bit better soils, the forestry company, apparently, hasn’t based their data on the natural conditions (biotope adjusted) and has integrated deciduous parts in pre selected stands. Thus other integrated data like moisture and ground vegetation type have the same bias. Such data complicates biotope adjusted felling and conservation in the landscape planning.