Dictionary

Common terms and concepts used in Swedish forestry:

Volume definitions

m³sk

Tree stem volume above the felling cut. Includes bark and top of the tree, but not branches.

m³fub

Volume of log(s) excluding bark.

m³fpb

Volume of log(s) including bark.

m³to

Volume of log(s) as given by a cylinder, with diameter = top diameter of the log under bark.

Mean diameters

Dgv - Basal area weighted mean diameter

Basal area weighted mean diameter (cm):



where
= number of tree objects, and
= diameter at breast height for tree object i, and
= tree expansion factor for the number of trees that tree object i represents.

Dg - Quadratic mean diameter

The diameter that corresponds to the mean basal area of the trees (cm).

Calculated as:


where
= sum of basal areas of trees (m²/ha) at breast height, and
= number of trees per hectar.
The multiplication with 100 is done to convert from m to cm.