Tree Height Measurement & GIS in Forestry
Measuring tree height is a key part of understanding forests. There are multiple methods, ranging from simple to advanced:
| Method | Tools Needed | Pros | Cons | Accuracy |
|---|---|---|---|---|
| Hillbilly / Backyard | Stick, tape, eyes, shadows | Free, easy, fun, can do anywhere | Rough estimate, not precise | Low |
| Scientific / Nondigital | Clinometer, hypsometer, tape measure | Accurate, widely used in forestry, reliable | Needs practice and math, slower than laser | Medium–High |
| Boujee / Modern | Laser rangefinder, total station, drone, LiDAR | Fast, highly accurate, can cover many trees quickly | Expensive, requires training, tech-heavy | High–Very High |
How to Try Each Method
Hillbilly / Backyard: Hold a stick at arm’s length aligned with the tree top, then use proportional comparison or measure shadows to estimate height.
Scientific / Nondigital: Use a clinometer to measure the angle to the tree top from a known distance. Apply basic trigonometry: Height = tan(angle) × distance + eye level.
Boujee / Modern: Laser rangefinders, drones, or LiDAR automatically calculate tree height and map trees in 3D. Great for research and professional surveys.
Additional Tree Age & Size Estimation Methods
1. Diameter at Breast Height (DBH) Estimation:
Description: Measure the tree’s diameter at ~1.3 m (4.5 ft) above the ground. Larger DBH often correlates with older age, but growth varies by species and competition. Suppressed or stressed trees may be misleading.
Math: Approximate age = DBH ÷ Average Growth per Year (species-dependent)
Pros: Quick, non-destructive, good for rough age estimates across a forest.
Cons: Highly variable; suppressed or damaged trees will give unreliable age.
Cost: Tape measure or caliper, free–$30 CAD.
2. Tree Ring Counting (Increment Core / Cross-Section):
Description: Count annual rings to determine tree age. Can be done using an increment borer (core sample) without cutting down the tree.
Pros: Highly accurate for age.
Cons: Can harm the tree if done incorrectly; not "willy-nilly." Requires some training and care to avoid infection or structural damage.
Cost: Increment borer ~$100–$200 CAD.
Note: These methods focus on age estimation, not height. Combine them with height measurement methods (arm, shadow, clinometer, rangefinder, LiDAR) for a complete picture of tree size and growth.