advertisement

Content Area: Natural Resources Lesson Heading: Forestry Activity Description: Wood Scaling Using trees near the school, students can practice determining height, diameter and cord wood in trees. After gathering measurements they can calculate board feet per tree knowing: - Area of a circle is A=r2 x pi. (Area = radius squared times 3.14). Once you have determined the area at DBH (diameter at breast height) use it to calculate cubic feet. - Cubic Feet = Area (ft) X Height (ft) / 4 (note: 4 is used to account for the taper of the tree) - There are 12 board feet of lumber for every one cubic foot, so multiply cubic feet by 12. You have calculated how many board feet of lumber your tree has. Design a worksheet for them to calculate with, such as: Calculations (show the math used to calculate answers) Tree # 1 Height: feet Diameter: inches Radius: inches / 12 = feet Area of tree at DBH: Volume of tree in cubic feet: Volume of tree in board feet: Materials Needed: Worksheet or piece of paper Ruler Biltmore Sticks or Tangent Height Gauges Clipboards Activity Length: 40 minutes for 10 trees, 35-45 minutes for calculations; gather materials Other Comments/Hints/Suggestions: Get students into groups according to the supplies they have, have them gather for a variety of sizes of trees to see difference in amount of board feet per tree depending on size.