Table 1 Visual appearance classes of 425 boards assessed by wood experts. The perceived look of the board surfaces in each class is described according to the experts’ sorting decision
Visual class | Number/class | Description |
|---|---|---|
1 | 40 | Vertical grain, clear surface, no knots |
2 | 24 | Vertical grain, few small black knots |
3 | 58 | Vertical grain, few small to medium black knots |
4 | 15 | Vertical grain, big sound knots |
5 | 30 | Vertical grain, compression wood (colour variation), stripy |
6 | 24 | Flat grain, few small black knots |
7 | 16 | Flat grain, high contrast in flat grain background structure |
8 | 13 | Flat grain, extra big sound knots |
9 | 26 | Flat grain, blurry background structure, medium black knots |
10 | 36 | Flat grain, pith and longitudinal cut centre knots |
11 | 9 | Flat grain, small to medium black knots |
12 | 27 | Flat grain, small sound knots, decent background structure, calm |
13 | 28 | Flat grain, pale background structure, various knot types |
14 | 29 | Flat grain, vivid, sound knots, marbling background structure |
15 | 50 | Flat grain, big sound knots in longer distances |
Total | 425 |