Although weight measurement is being used increasingly for sale of logs, particularly in the radiata pine industry, a majority of sawlog sales are still on a volume basis. Methods of deriving log volume are therefore still important. Log length Log length is measured in metres and decimetres, the precision of measurement depending on the use to be made of the figures. Log diameter Log diameter is measured in cm. Again the precision of measurement depends on the use to be made of the figures.
Measurement can be direct or indirect.
Diameter tapes for log measurement are usually made of steel. They should be wound tightly around the circumference of the log in a plane at right angles to the long axis of the log. Errors in assuming that the log cross-section is circular can be judged from the table below. The geometric mean of at least two calipered diameters will lead to minimising the error in this assumption. Stems of deliquescent trees approximate frusta of the above solids.