Table 2. Definitions and abbreviations of the variables used in this paper.

	Description
Tree-level variables
DBHt	Diameter of the tree at 1.3 m at time t (mm)
Aget	Age of the tree at time t
HDt	Ratio of total tree height to DBH calculated for each year of growth at time t
KSRt	Ratio of total knot area increment to the stem basal area increment at time t
Ring-level variables
RN	Annual ring number from the pith of the main stem at the level of each knot
RWt	Annual ring width at time t (mm)
lt	Distance from the pith of the stem at time t (mm)
GUpos	Relative position of the knot initiation point along the annual growth unit (varies from 0 to 1)
Hk	Position of the initiation point of the knot along the stem (ground level = 0) (m)
Knot-level variables
ΔDt	Annual increment of the knot diameter from time t − 1 to t (mm)
Dt	Predicted knot diameter at time t (mm)
ΔZt	Annual increment of the trajectory of the knot from time t − 1 to t (mm)