Quality requirements
1. Single branches
on the edge ½ of thickness
on the cut firmly grown knots are not limited
one the plan ¼ of width
maximum diameter of branches 50 mm
edge-filament branches longer than ⅓ of width not permitted
2. Groups of branches (within the ⅓
distance of 15 cm from the double length)
3. Width of flutes up to 6 mm
4. Cracks (due to cold, lightning, ring) not permitted
(radial) permitted
5. Discolorations (blue stains) not permitted
6. Rot not permitted
7. Resin galls permitted
8. Grown in bark max. width 10 mm
max. length 2 widths
max. depth ⅓ thickness
9. Bark at the branches not permitted
10. Wane not permitted
11. Insect attack not permitted
12. Longitudinal curvature 5 mm / 2 m
13. Torsion not permitted
14. Transverse curvature (concave) not permitted
15. Pith permitted
16. Deviations from dimensions (thickness
and width) -0 + 2 mm