DynaRoot Root Testing System


The stability of urban trees is a key question that affects everyone. Diseased and unstable urban trees pose much risk for everyone, and are a serious liability for municipalities in case of an accident. Tree stability assessment is therefore of the utmost importance. At present, there is only one accepted method for tree stability assessment. The pulling test, while well established and accepted, has several drawbacks, both in terms of reliability and ease of use.

Our new concept, the dynamic root stability determination, however, is based on real life wind loads, and is therefore more appropriate for assessing real life risks. It is also much simpler to carry out than the traditional pulling test, with the only drawback being that it requires windy weather.

The DynaRoot system should be used on days with at least 25 km/h (15 mph) wind gust velocities. Setting up the measurement involves the following steps.
  1. Assemble the anemometer tower in the vicinity of the tree(s) to be assessed. Attach the anemometer on the top, and erect the tower. Wind velocity readings are sent to, and data is collected at the instrument box located at the bottom of the tower.
  2. Start recording data by pressing the START button located in the instrument box.
  3. Mount the inclinometer on the root collar of the tree to be assessed.
  4. Start recording data by pressing the START button located on the side of the instrument box.
  5. Repeat the previous 2 steps if you have more inclinometers and want to assess multiple trees.
  6. Record data for at least 3 hours (the longer the better).
  7. After the recordings are finished, transfer the acquired data to a PC by removing the internal SD card or by switching the instruments to Wi-Fi mode.
  8. Load the data into the DynaRoot evaluation software and calculate the safety factor.

The system consists of the following 3 components.
Dual axis anemometer

An instrument for measuring wind velocity at or near the tree to be evaluated. The closer to the better, but, depending on wind velocity DynaRoot may provide reliable data even with measurements taken several kilometres/miles away. The anemometer provides wind velocity data of sufficient frequency, Ideally the anemometer should be clear of buildings or other objects that may obstruct the wind, at a height of at least 10m.

Dual axis inclinometer

An instrument affixed to the root collar that measures the inclination of the trunk in two perpendicular directions. The instrument provides very accurate inclination data with sufficient frequency.

DynaRoot evaluation software

A PC software for evaluating wind velocity and inclination. The data, recorded over a period of several hours, are transferred from the anemometer and inclinometer on memory cards or wirelessly via Wi-Fi. The software breaks the data down into shorter intervals, and calculates statistical parameters for each interval that are used for the tree stability evaluation.

  • Inclinometer recorder (min 1 pcs., recommended 3 pcs.)
  • Base plate with ball head
  • Screw and screwdriver
  • LED display panel
  • Software on CD
  • User's manual
  • Lead batteries and charger
  • Alu case
  • Anemometer (ball type or ultrasonic) and recorder
  • 10 m portable pole
    • Alu tube (6 sections)
    • Steel anchor rod (3 pcs.)
    • 12 m long rope (3 pcs.)
    • Case
Dual axis anemometer
Sampling rate
1 Hz
Measurement range
0-150 km/h
0.2 km/h
Integrated GPS
Maximal SD card size
yes, IP65

Dual axis inclinometer
Measurement range
Integrated GPS
Maximal SD card size
yes, IP65
Operating voltage and currents
12 V, 20 mA

  •  DynaRoot for Windows (version: 1.0.37, size: 2,7 MB)
  •  DynaRoot Dynamic Root Evaluation System (size: 4.1 MB)
  •  Sample .fdr file for DynaRoot - Cherry (size: 4.2 MB)
  •  Sample .fdr file for DynaRoot - Spruce (size: 6.8 MB)