# 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 |