BARK STRIPPING OF YOUNG PINUS-SYLVESTRIS BY ALCES-ALCES ON THE INDIVIDUAL, STAND, AND LANDSCAPE LEVEL IN SWEDEN

Physical characteristics of Scots pine (Pinus sylvestris L.) trees bar k stripped by moose (Alces alces L.) and frequencies of bark stripping were quantified at the Grimso Wildlife Research Area in south-central Sweden during July 1995. Twenty-one young Scots pine stands evenly di stributed over two areas of differing forest productivity were include d in the study. Each stand was systematically plot-surveyed to determi ne the frequency of affected Scots pine trees. Additionally, we quanti fied data (i.e., 13 variables) on 420 recently (i.e., spring 1995) bar k-stripped pine trees located through visual walking surveys of each s tand. Less than 3% of the trees within the susceptible height range (1 .5-4.0 m) were bark stripped annually, and 99% of these trees were bet ween 1.5 and 4 m in height and wounds were concentrated within the 3- and 4-year-old internodes. There was a weak positive relationship betw een frequency of bark stripping and forest productivity at the stand a nd landscape levels, whereas weak negative relationships were found be tween bark-stripping frequency and stand size and bark-stripping frequ ency and pine stem density. Overall, the results suggest bark strippin g has a minor impact on the trees. Forestry practices to reduce bark-s tripping damage are discussed.