Board Foot Volume of a Tree based on the Scribner Log Rule
Approximate the gross board foot volume of a tree using the Scribner Log Rule
The Scribner board foot (fbm) volume is calculated based on the number of 16-foot sawlogs the tree contains in merchantable lumber. The diameter of the tree is measured at breast height (DBH 4½ feet above the ground) The results represent the gross board foot amount as reported in the Scribner Girard form class 78 table.
How to enter an amount in the "Number of 16 Foot Sawlogs" field of the calculator
The calculation is based on the number of 16-foot sections there are in the tree. The Scribner form class 78 table shows results based on full 16-foot sections and an 8-foot section if needed.Therefore a 16-foot section is entered as 1
Two 16 foot sections are entered as a 2
The smallest section that can be calculated for is 8 feet, entered as 0.5
a 10-foot tree height is entered as 0.625
a 24-foot tree height is entered as 1.5 (1 for a 16-foot length and 0.5 for the 8-foot length)
a 31-foot tree height is entered as 1.9375 (1 for a 16-foot length and 0.9375 for the 15-foot length)
a 33-foot tree height is entered as 2.0625 (2 for a 32-foot length (2x16') and 0.0625 for the one-foot length)
See table below calculator for decimal values
Scribner Log Rule
Calculation
- the number of 16-foot sawlogs in the tree stem or part thereof (see table)
- diameter of a tree measured at breast height
Result
- board foot volume of the tree based on the Scribner log scale table for standing tree volumes.
| Tree Height | ||
| Height in Feet | Decimal Value | |
| 1' | 1/16 of a foot = | 0.0625 |
| 2' | 2/16 of a foot = | 0.125 |
| 3' | 3/16 of a foot = | 0.1875 |
| 4' | 4/16 of a foot = | 0.25 |
| 5' | 5/16 of a foot = | 0.3125 |
| 6' | 6/16 of a foot = | 0.375 |
| 7' | 7/16 of a foot = | 0.4375 |
| 8' | 8/16 of a foot = | 0.5 |
| 9' | 9/16 of a foot = | 0.5625 |
| 10' | 10/16 of a foot = | 0.625 |
| 11' | 11/16 of a foot = | 0.6875 |
| 12' | 12/16 of a foot = | 0.75 |
| 13' | 13/16 of a foot = | 0.8125 |
| 14' | 14/16 of a foot = | 0.875 |
| 15' | 15/16 of a foot = | 0.9375 |
| 16' | 16/16 of a foot = | 1 |
| 32' | 2 | |
| 48' | 3 | |
| 64' | 4 | |
| 80' | 5 | |
| 96' | 6 | |
| 112' | 7 | |
| 128' | 8 | |
