Does the DBH of a tree mean circumference or diameter?

The DBH of a tree refers to its diameter.

The DBH of a tree refers to the diameter from the surface of the tree trunk off the ground to the tree, which measures the height of a person's chest. The trunk diameter at1.3m is the average of the maximum and minimum values of the deformed part.

DBH is 30cm, and the half radius is15cm. Draw a circle with a radius of 15 cm, that is, the cross section of the trunk at a distance of 1.3 m from the ground and a DBH of 30 cm.

Tree species not suitable for DBH measurement

1, shrub

The main reason is that the growth of their main stems is relatively small, mainly the growth of branches and leaves, and they are often used as foliage plants, and the tree conditions are not suitable, so it is more appropriate to calculate their size with height (H) and crown width (W).

2. Grass flowers

Most of them belong to herbaceous flowers or perennial flowers, and the specifications are calculated according to the size of the nutrition cup and the height of the crown.

3. Short-branched unipolar tree

Trees with branch points less than 120cm belong to young trees with short branches, and the height of single stem does not reach the range of DBH height measurement. It is more appropriate to measure by meter diameter or ground diameter, mainly depending on the height of the branch point.

4. The ground cages are clustered on the trees.

For example, common ground cage osmanthus trees, clustered Lagerstroemia indica trees, clustered Pistacia chinensis trees, clustered camphor trees and so on. The young trees of these species mainly appreciate their crown and natural growth, and the measurement methods of ground diameter, meter diameter and breast diameter are not suitable. The total height (h), crown width (w) and tree beauty can be combined to calculate their specifications.