Hobbies And Interests
Things You'll Need
Instructions
Mark out a circle measuring 52 feet in diameter, which is equal to 1/20th of an acre, using a tape measure. Have a helper stand in one place holding the tape measure and pull out 26 feet of tape. Walk around your helper in a circle, which will create a circle with a diameter of 52 feet across.
Using the tape measure, measure the diameter of all the trees within the circle. The diameter of the tree should be measured 4.5 feet off the ground, which is considered breast height. Record the measurements for all the trees. Saplings should not be measured as they would not be cut down if the land was forested for timber.
Divide the diameter of each tree by 2 to obtain the radius of each tree. The radius of the tree should then be squared. For example, if the diameter of the tree is 10 inches, the radius will be 5 inches. Squaring 5 inches equals 25 inches squared.
Multiply the squared radius by pi, or 3.14 to obtain the basal area of the tree. Using the previous example 25 inches squared multiplied by 3.14 equals 78.5 inches squared. Complete this calculation for all trees within the circle.
Add up the basal area of all the trees in the circle. This will provide the sum of the total basal area for the 1/20 of an acre plot.
Multiply the basal area sum by 20, since the original area was 1/20 of one acre to obtain the basal area per acre in inches.
Convert the basal area to feet by dividing the average by 144 inches. This will convert square inches into square feet.