New results from plot no. 5 at sperlingsholm estate in southwestern Sweden in the European Stemnumber experiment in <i>picea abies</i>

Abstract

Abstract Results from surveys of the Swedish experiment in 1976, 1981, 1983 and 1985 are presented. The experiment was thinned when the average dominant heights were 10.3, 13.7 and 16.2 m, respectively. The increment of stem volume for the periods 1977–81 and 1982–85 is given in Tables 1 and 2, respectively. In comparison with unthinned control subplots, the volume increment for the periods 1977–81 and 1982–85 was reduced by the following relative figures: treatment 2 with strip road width 3.5 m, 9 and 17% respectivelytreatment 3 with strip road width 3.5 m, 16 and 14% respectivelytreatment 4 with strip road width 5.0 m, 7 and 20% respectively The increment of single trees closest to the edge of the strip road was greatly stimulated. This increment effect reaches about 3 m into the stand from the edge of the strip road. Functions for diameter and basal area increment of single trees are presented for the periods 1977–81 and 1982–85 (86) where the distance to the edge of the rack is included as an indicator variable. Key words: Picea abiesdiameter and volume incrementstrip road