The B6 Abbreviated Tariff

The B6 Abbreviated Tariff, as described in Forest Mensuration: A handbook for practitioners ('the blue book') uses pre-defined volume-basal area ratios (VBARs) to estimate volume/ha from a basal area measurement.

These tariff tables are UK specific, and should be used with caution.

Learn more about the B6 tariff method and its limitations

Using the calculator

This calculator can process individual plots, but to follow the 'blue-book' more closely, it is preferable to enter all of your diameter measurements for a single-species strata at once, using average top height and the sum of plot areas.

To derive tariff number alone, simply enter species and top height with no diameter measurements.

Diameter distribution is also summarised graphically, along with the VBAR which has been applied.