Free Access

Table IV

Results of mixed models testing the effect of neighboring species and competition indices (CI, see Tab. II) on different growth variables in Scots pine. Diameter growth was analyzed as repeated measures using diameter growth of the latest 10 y. Sb, Sp, and Sl give the mean value (±95% confidence interval) of each response variable with silver birch, Scots pine, and Siberian larch as neighbors, respectively.

Variable Effect Num df Den df F P Sb Sp Sl
Height increment (cm/year) 42.7 (5.3) 40.1 (5.3) 42.3 (5.6)
Neighbor 2 64.4 2.6 0.0801
CI11 1 65.3 10.1 0.0023
Diameter growth (mm/year) 2.7 (0.5) 2.8 (0.5) 3.3 (0.7)
Neighbor 2 12.8 1.8 0.2002
Year 9 381 20.9 < 0.0001
Age 1 21.9 0.1 0.7142
CI1 1 14.5 0.1 0.7637
Shoot length (annual shoot length/total branch length, cm) 3.1 (0.5) 3.6 (0.4) 4.1 (0.7)
neighbor 2 73.4 3.6 0.0322
CI4 1 57.7 12.9 0.0007
Branch number (branches/cm crown length) 0.10 (0.02) 0.11 (0.02) 0.13 (0.02)
Neighbor 2 62.3 4.1 0.0204
CI4 1 67 5.4 0.0231
Whorl distance (cm) 51.9 (6.5) 47.6 (6.5) 47.9 (6.7)
Neighbor 2 138 3.7 0.0278
Year 9 500 13.9 < 0.0001
age 1 30.5 2.5 0.4013
CI4 1 138 2.6 0.0996