Most of the decayed knots are located in the second middle logs and top logs.
The only sections that were totally free of decayed knots were sections from 0 to 0.
Other important reasons for reduction in sawn timber grade were number of green knots, size of red knots, number of black knots, and number of decayed knots.
Decayed knots decrease the value more than green knots do.
After the top diameter of a log, the most significant predictor is the number of decayed knots at the section from the base to 0.