Basal area

Basal area is the area of a given section of land that is occupied by the cross-section of tree trunks and stems at the base. The term is used in forest management and forest ecology.

In most countries, this is usually a measurement taken at the diameter at breast height (1.3m or 4.5 ft) of a tree above the ground and includes the complete diameter of every tree, including the bark. Measurements are usually made for a plot and this is then scaled up for 1 hectare of land for comparison purposes to examine a forest's productivity and growth rate.

To estimate a tree's basal area ${\displaystyle BA}$, use the tree's diameter at breast height ${\displaystyle DBH}$ in inches with the following formula:

${\displaystyle BA={\frac {\pi \times (DBH/2)^{2}}{144}}}$

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