Overview
The DV dendrometer is used for high-precision and continuous measurement of vertical changes in dimension and/or curvature of tree stems. This device is suitable for long-term in outdoor conditions. Due to their extremely low power consumption, Ecomatik dendrometers are ideal for battery-powered solutions, e.g., in IoT applications.
The DV dendrometer is designed to continuously measure vertical changes (not growth) of trees. Tree stems and their respective sections vary in length and curvature, according to water status (short- to mid-term), wind direction and wind speed (short-term to permanent), snow and fruit load (mid-term to permanent), and unbalanced growth or loss of crown parts (long-term to permanent). Transcription of vertical changes, along with their directional information, provides valuable information to assess water status and static properties of a tree (stress-strain relationship, mechanical load/stability, etc.). Parallel measurements with three vertical dendrometers (each oriented in three different cardinal directions) are necessary for a complete overview of vertical changes.
Advantages
- Stress-strain relationship computation
- Maximum stability against wind, snow, falling branches and fruit
- Ideal for long-term measurements
Limits
- Installation (drilling and screwing in the anchoring screws) damages the tree trunk (which could be minimized with wound closure resin).
- Only suitable for diameters > 8 cm
Models
| Models | Suitable for diameter | Measurement range |
|---|---|---|
| DV | > 8 cm | 11 mm |
Technical data
Sensor model name | Vertical Dendrometer Type DV |
Scope of application | Stems or branches |
Suitable for diameter | 5 – 32 cm |
Special features/limitations | 2x trunk screws for mounting |
Measurement range | 11 mm linear |
Resolution | Data logger dependent e.g.: CR300 series: 0.01 µm Dendrometer logger DL18: 0.2 µm |
Accuracy | Dendrometer dependent: max. ± 4.5% of the measured value (stable offset) Data logger dependent e.g.: CR300 series: ± (0.04% of the measured value + 0.3 µm) Dendrometer logger DL18: ± (0.1% of the measured value + 0.45 µm) |
Output signal | Analogue, 0V to Vex (excitation supply voltage) |
Temperature drift of the sensor | < 0.2 µm/°C in the whole measurement range |
Temperature coefficient of the stem embracing cable wire | < 1.4 ×10-6/K |
Linearity | < 1% |
Operational conditions | Normal outdoor field conditions, -25 to 70 ° C, 0 to 100% relative air humidity; unsuitable underwater and below snow cover |
Weight (sensor without cable) | 13 g |
Power supply | Vex (! stabilized !) 0.5 to 10 VDC, Power consumption max. 0.28 µWh per measurement |
Material | Stainless steel and aluminium |