Taking Measurements
Learn how to accurately measure trees using the TreeMapper mobile app.
Overview
Accurate tree measurements are essential for tracking growth and assessing the success of your restoration efforts. TreeMapper provides tools for recording height, diameter, and other metrics with built-in validation to ensure data quality.
Measurement Types
Height/Length
Tree height is measured from the ground to the top of the tree. TreeMapper supports different units based on your location:
- Metric countries (ISU): Enter height in meters
- Non-metric countries: Enter height in feet (automatically converted to meters for storage)
Diameter Measurements
TreeMapper automatically determines which diameter measurement to use based on tree height:
Diameter at Breast Height (DBH)
For trees taller than 1.3 meters (4.3 feet):
- Measured at 1.3 meters (breast height) above the ground
- Standard forestry measurement for established trees
- Entered in centimeters (metric) or inches (non-metric)
Basal Diameter
For trees shorter than 1.3 meters:
- Measured at the base of the tree, near ground level
- Used for seedlings and young trees
- Same unit options as DBH
The app automatically switches between "DBH" and "Basal Diameter" labels based on the height you enter, ensuring the correct measurement protocol is followed.
Taking Measurements
When adding measurements to a tree, follow these steps:
Enter Height
Input the tree height in the appropriate unit for your region
Enter Diameter
Input DBH (for trees >1.3m) or basal diameter (for shorter trees)
Add Tree Tag (Optional)
Enable the tag switch and enter an alphanumeric tag ID if using physical tags
Take Photo
Capture a photo of the tree for visual documentation
Save Measurements
Confirm and save the measurement record
Measurement Validation
TreeMapper includes built-in validation to help ensure your measurements are botanically reasonable:
Height-to-Diameter Ratio
The app checks the ratio between height and diameter to identify potentially erroneous measurements. If the ratio falls outside expected ranges for typical trees, you'll see an alert.
What Happens When Validation Fails?
- An alert appears explaining the potential issue
- You can review and correct your measurements
- You can choose to save anyway if the measurements are accurate for an unusual tree
Input Validation
- Values must be positive numbers
- Decimal format is supported (e.g., 2.5 meters)
- Empty values are not allowed for required fields
Tree Tags
Tree tags provide a physical-to-digital link for tracking individual trees in the field:
- Toggle the tag switch to enable tag input
- Enter an alphanumeric tag ID that matches the physical tag on the tree
- Tags must be unique within the intervention
- Use consistent tagging protocols across your project
Location Data
When you take measurements, TreeMapper automatically captures your current GPS location. This provides:
- Geographic reference for the measured tree
- Location accuracy information
- Timestamp of the measurement
Unit Conversion
TreeMapper handles unit conversion automatically to ensure data consistency across all users:
| Measurement | Input Unit | Stored Unit |
|---|---|---|
| Height (Metric) | Meters | Meters |
| Height (Non-metric) | Feet | Meters |
| Diameter (Metric) | Centimeters | Centimeters |
| Diameter (Non-metric) | Inches | Centimeters |
Best Practices for Accurate Measurements
Height Measurement Tips
- Use proper tools: A clinometer or hypsometer improves accuracy for tall trees
- Stand at known distance: Position yourself at a consistent distance from the tree
- Identify the top: Clearly identify the highest point of the crown
- Account for slope: Measure from the uphill side on slopes
Diameter Measurement Tips
- Use a diameter tape: D-tapes give direct diameter readings from circumference
- Measure perpendicular: Hold the tape perpendicular to the tree trunk
- Avoid irregularities: If there's a bulge or damage at breast height, measure slightly above or below
- Record multiple stems: For multi-stemmed trees, measure each stem separately
General Tips
- Be consistent: Use the same measurement technique across all trees
- Double-check unusual values: Re-measure if numbers seem off
- Document conditions: Note any factors affecting measurement accuracy
- Take photos: Photos provide visual verification of measurements