When taking caliper measurements, where should it be measured from?

The correct measurement point for caliper measurements is at the root collar. The root collar, also known as the root flare or the basal area, is the area where the trunk transitions into the root system. Measuring at the root collar provides a standard reference point that is consistent across different types of trees and helps ensure accurate and reliable measurements.

This location is significant because it reflects the tree's structural integrity and the health of its root system. Measuring too high on the trunk, such as at the highest branch or midway up the trunk, does not account for the important zone where the roots and trunk connect, which can lead to discrepancies in assessing the tree's growth and overall size.

By taking the measurement at the root collar, arborists can obtain a more accurate representation of the tree's size that can be used for various purposes, including inventory assessments, growth monitoring, and in adherence to industry standards. This practice is essential for effective tree management and health evaluations.