Basal Area Calculator
Basal Area Calculator
To calculate Basal Area, input Tree Diameter (measured at breast height – DBH), select your preferred measurement units (inches / centimeters) in calculator.
For Stand Basal Area, input the Plot Size and number of trees. The calculator provides individual tree basal area and total stand basal area per unit area (acre or hectare).
How to Calculate Basal Area?
To calculate Basal Area, measure tree’s Diameter at Breast Height (DBH) at 4.5 feet (1.37 meters) above ground level. Convert the diameter to radius and use the formula for circle area (πr²).
For Stand Basal Area, multiply by number of trees and convert to per acre/hectare basis using plot size. Consider tree density and plot sampling techniques for accurate forest measurements.
Formula for Basal Area
Individual Tree Basal Area:
BA = π × (DBH/2)²
where:
BA = Basal Area (square feet/meters)
DBH = Diameter at Breast Height
π = 3.14159
Stand Basal Area Per Acre:
Stand BA = (BA × Number of Trees × 43,560) ÷ Plot Size
where:
43,560 = Square feet per acre
Plot Size = Area in square feet
Metric Conversion:
BA (m²) = π × (DBH in cm ÷ 200)²
Stand BA (m²/ha) = (BA × Number of Trees × 10,000) ÷ Plot Size
where:
10,000 = Square meters per hectare
Example 1: Single Large Oak
- DBH = 24 inches
- Basal Area = 3.14 square feet
- Tree Type = Oak
- Measurement Height = 4.5 feet
- Application = Individual Tree Assessment
Example 2: Pine Stand
- Average DBH = 12 inches
- Trees per Plot = 10
- Plot Size = 1/10 acre
- Stand BA = 120 square feet per acre
- Application = Forest Management
Example 3: Mixed Hardwood Plot
- Multiple DBH = 8-20 inches
- Trees per Plot = 15
- Plot Size = 1/4 acre
- Stand BA = 85 square feet per acre
- Application = Timber Inventory
Example 4: Young Forest
- Average DBH = 6 inches
- Trees per Plot = 25
- Plot Size = 1/20 acre
- Stand BA = 60 square feet per acre
- Application = Growth Assessment
Example 5: Metric Measurement
- DBH = 45 centimeters
- Plot Size = 400 square meters
- Trees per Plot = 8
- Stand BA = 28 square meters per hectare
- Application = Research Plot
What is Basal Area?
Basal Area is cross-sectional area of a tree stem measured at Breast Height (4.5 feet or 1.37 meters above ground). It represents the area of a horizontal slice through the trunk at this height. For forest stands, Basal Area per Acre indicates stand density and is crucial for Forest Management, Timber Assessment, and Ecological Studies.