DynaTree Root and Trunk Testing System

 The dynamic pulling test

 Requires wind gusts at least 25 km/h

 Uses real wind instead of cable

 As the tree is measured in real windy situation, the effect of the surroundings, the actual crown and soil conditions are included

 Let the wind work for you :)

The DynaTree 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. Mount the elastometers onto the trunk of the tree to be assessed. Connect them to the central unit.
  5. Start recording data by pressing the START buttons located on the side of the instrument box.
  6. Repeat the previous 3 steps if you have more inclinometers and/or elastometers want to assess multiple trees.
  7. Record data for at least 3 hours (the longer the better).
  8. 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.
  9. Load the data into the DynaTree evaluation software and calculate the safety factor.

The system consists of the following 4 components.

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.


An instrument attached to the trunk for measuring the micro elongation of the trunk.

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
  • 2 elastometers in quick mounting house
  • Dual elastometer box
  • Screw and screwdriver
  • 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
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
Sampling rate
10 Hz
Integrated GPS
Maximal SD card size
yes, IP65
Operating voltage and currents
12 V, 20 mA

30x30x270 mm
250 mm
Sampling rate
10 Hz
0.3 μm
Power source
2 pcs. of 9 V batteries