Table 1. Relative distribution of the productive forest area (%) distributed over age class (years) and site index (H40 - m).
  Site index  
Age class < 7.5 [7.5, 9.5[ [9.5, 12.5[ [12.5, 15.5[ [15.5, 18.5[ [18.5, 21.5[ ≥ 21.5 Total
0–10   0.02 0.02 0.3 0.3 0.2 0.04 0.9
11–20 0.1 0.2 0.1 1.1 1.0 0.4 0.02 2.9
21–30 0.02 0.5 0.2 3.4 3.9 0.7 0.02 8.7
31–40 0.01 0.3 0.2 3.5 1.9 0.7 0.1 6.8
41–50 0.1 1.2 0.3 5.0 4.6 1.2 0.3 12.6
51–60 0.3 1.1 0.3 6.8 4.2 1.6 0.7 15.1
61–70 0.1 0.7 0.1 4.0 3.0 1.4 0.2 9.5
71–80 0.3 0.9 0.4 2.1 1.7 0.6 0.0 6.1
81–90 0.8 1.3 0.2 2.3 1.5 0.2 0.01 6.3
91–100 0.4 1.2 0.3 1.8 1.2 0.1   5.1
101–110 1.1 2.4 0.5 2.4 1.0 0.1   7.5
111–120 0.7 1.2 0.5 1.3 0.7 0.1   4.6
> = 121 5.1 3.7 1.4 2.9 0.6 0.0   13.8
Total 9.2 14.7 4.7 36.8 25.8 7.5 1.4 100.0
Table 2. Distribution of the stands over size classes.
Size class (ha) 0.00– 0.25 0.25– 0.50 0.50– 0.75 0.75– 1.00 1.00– 1.25 1.25– 1.50 1.50– 1.75 1.75– 2.00 2.00– 2.25 2.25– 2.50 2.50– 2.75 2.75– 3.00
No. of stands 404 858 953 826 853 893 972 912 762 598 468 375
Table 3. List of problems and the respective types of constraints added successively to the general model.

Problem 		Type of constraint
Controlled harvest volume Minimum old-growth forest area Maximum open area
1- Non Constrained (Nc) - - -
2- Controlled harvest volume (Ch) X - -
3- Controlled harvest volume + Minimum old-growth forest area (ChOg) X X -
4- Controlled harvest volume + Minimum old-growth forest area + Maximum open area (ChOgOa) X X X
Table 4. NPV of each problem and NPV-loss between problems.

Problem 		NPV NVP-loss between problems (%)
(mill. EUR) 2- Ch 3 - ChOg 4- ChOgOa
1- Nc 67.8 2.1 15.9 21.8
2- Ch 66.4 - 14.2 20.2
3- ChOg 57.0 - - 7.0
4- ChOgOa 53.0 - - -
1

Fig. 1. Harvested volume (1000 m3) for different harvest options over planning periods and problems. First period harvested volume of Problem 1: clear cut = 741 000 m3, seed tree cut = 305 000 m3 and total = 1 071 000 m3. Problem 1. Non-Constrained (1-Nc); Problem 2. Controlled harvest volume (2-Ch); Problem 3. Controlled harvest volume + Minimum old-growth forest area (3-ChOg); Problem 4. Controlled harvest volume + Minimum old-growth forest area + Maximum open area (4-ChOgOa).

2

Fig. 2. Total regenerated area (ha) and regenerated area (%) allocated to planting over planning periods and problems. First period total regenerated area for Problem 1 = 4718 ha. Problem 1. Non-Constrained (1-Nc); Problem 2. Controlled harvest volume (2-Ch); Problem 3. Controlled harvest volume + Minimum old-growth forest area (3-ChOg); Problem 4. Controlled harvest volume + Minimum old-growth forest area + Maximum open area (4-ChOgOa).

Table 5. Old-growth forest areas (ha) over the planning periods, and share of old-growth forest that remain over planning periods for Problems 3 and 4.
Problems Old-growth forest
area (ha) 		Planning
periods 		2 3 4 5 6 7 8 9 10
3- ChOg 768 1 100 100 100 100 97 93 93 89 87
1040 2   100 100 100 97 90 89 85 83
1487 3     100 100 96 88 87 84 83
1870 4       100 95 87 85 82 81
2502 5         96 87 85 82 81
2502 6           91 90 87 85
2502 7             99 95 94
2502 8               97 95
2502 9                 98
2502 10                  
4- ChOgOa 776 1 99 99 99 99 94 88 85 83 81
1048 2   100 100 100 94 83 80 77 76
1491 3     100 100 94 84 82 78 75
1870 4       100 93 83 80 75 72
2502 5         94 84 80 75 72
2502 6           90 86 80 77
2502 7             96 89 85
2502 8               92 88
2502 9                 95
2502 10                  
3

Fig. 3. Total area (ha) in open state over planning periods and problems. Problem 1. Non-Constrained (1-Nc); Problem 2. Controlled harvest volume (2-Ch); Problem 3. Controlled harvest volume + Minimum old-growth forest area (3-ChOg); Problem 4. Controlled harvest volume + Minimum old-growth forest area + Maximum open area (4-ChOgOa).

4

Fig. 4. Open state and old-growth forest areas for problem 3 (left) and problem 4 (right) in period 5. Old-growth forest (light grey), young forest (grey) and areas in open state (black).

5

Fig. 5. Maximum energy potential from harvest residues over planning periods and problems. First period energy potential for Problem 1 = 124 GWh. Problem 1. Non-Constrained (1-Nc); Problem 2. Controlled harvest volume (2-Ch); Problem 3. Controlled harvest volume + Minimum old-growth forest area (3-ChOg); Problem 4. Controlled harvest volume + Minimum old-growth forest area + Maximum open area (4-ChOgOa).