**2. Round wood**

Dimensions and volume of wood together with its quality are basic data accompanying wood from the stage of a young stand until the end of the wood product service life. In many cases, it is sufficient to know only approximate values of dimensions and volume, e.g. growing stock, the volume of cut, and roundwood supplies on log yards. On the other hand, operations controlling production or where wood is the subject of business – goods, are sensitive to accuracy.

The tree stem or its part, log, is a body, the form of which is mostly compared to a truncated cone, paraboloid or cylinder. However the real form does not correspond to any regular geometric body. Moreover, it is affected by considerable individual diversity given by the tree species, tree age, site, tree position in the stand, care of the stand, type and extent of attack, mechanical damage either natural or caused by man activities and many other effects. From the aspect of dimensions, these effects become evident in various taper, sweep, flattening, root swelling, buttress, burrs and cracks. Production defects of wood are represented by remains of branches and damage to the stem surface at branching and handling, chamfer cuts, hinges (holding wood) after cutting or bucking (cross-cutting), cracks etc. All these properties have to be taken into account at stem or log measurements and at the evaluation of their dimensions and volume. Bark – its thickness and condition, represents a separate problem at the measurement of wood.
